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Pai V, Bileck A, Hommer N, Janku P, Lindner T, Kauer V, Rumpf B, Haslacher H, Hagn G, Meier-Menches SM, Schmetterer L, Schmidl D, Gerner C, Garhöfer G. Impaired retinal oxygen metabolism and perfusion are accompanied by plasma protein and lipid alterations in recovered COVID-19 patients. Sci Rep 2024; 14:8395. [PMID: 38600099 PMCID: PMC11006918 DOI: 10.1038/s41598-024-56834-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 03/12/2024] [Indexed: 04/12/2024] Open
Abstract
The aim of the present study was to investigate retinal microcirculatory and functional metabolic changes in patients after they had recovered from a moderate to severe acute COVID-19 infection. Retinal perfusion was quantified using laser speckle flowgraphy. Oxygen saturation and retinal calibers were assessed with a dynamic vessel analyzer. Arterio-venous ratio (AVR) was calculated based on retinal vessel diameter data. Blood plasma samples underwent mass spectrometry-based multi-omics profiling, including proteomics, metabolomics and eicosadomics. A total of 40 subjects were included in the present study, of which 29 had recovered from moderate to severe COVID-19 within 2 to 23 weeks before inclusion and 11 had never had COVID-19, as confirmed by antibody testing. Perfusion in retinal vessels was significantly lower in patients (60.6 ± 16.0 a.u.) than in control subjects (76.2 ± 12.1 a.u., p = 0.006). Arterio-venous (AV) difference in oxygen saturation and AVR was significantly lower in patients compared to healthy controls (p = 0.021 for AVR and p = 0.023 for AV difference in oxygen saturation). Molecular profiles demonstrated down-regulation of cell adhesion molecules, NOTCH3 and fatty acids, and suggested a bisphasic dysregulation of nitric oxide synthesis after COVID-19 infection. The results of this study imply that retinal perfusion and oxygen metabolism is still significantly altered in patients well beyond the acute phase of COVID-19. This is also reflected in the molecular profiling analysis of blood plasma, indicating a down-regulation of nitric oxide-related endothelial and immunological cell functions.Trial Registration: ClinicalTrials.gov ( https://clinicaltrials.gov ) NCT05650905.
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Affiliation(s)
- Viktoria Pai
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Andrea Bileck
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090, Vienna, Austria
- Joint Metabolome Facility, University of Vienna and Medical University Vienna, Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Patrick Janku
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Theresa Lindner
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Victoria Kauer
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Department of Medicine IV for Infectious Diseases and Tropical Medicine, Clinic Favoriten, Vienna, Austria
| | - Benedikt Rumpf
- Department of Medicine IV for Infectious Diseases and Tropical Medicine, Clinic Favoriten, Vienna, Austria
| | - Helmuth Haslacher
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Gerhard Hagn
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090, Vienna, Austria
| | - Samuel M Meier-Menches
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090, Vienna, Austria
- Joint Metabolome Facility, University of Vienna and Medical University Vienna, Vienna, Austria
- Institute of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Christopher Gerner
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090, Vienna, Austria.
- Joint Metabolome Facility, University of Vienna and Medical University Vienna, Vienna, Austria.
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.
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Vasile VA, Pirvulescu RA, Iancu RC, Garhöfer G, Schmetterer L, Ghita AM, Ionescu D, Istrate S, Piticescu RM, Cursaru LM, Popa-Cherecheanu A. Titanium Implants Coated with Hydroxyapatite Used in Orbital Wall Reconstruction-A Literature Review. Materials (Basel) 2024; 17:1676. [PMID: 38612189 PMCID: PMC11012370 DOI: 10.3390/ma17071676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/01/2024] [Accepted: 04/04/2024] [Indexed: 04/14/2024]
Abstract
With the increasing incidences of orbital wall injuries, effective reconstruction materials and techniques are imperative for optimal clinical outcomes. In this literature review, we delve into the efficacy and potential advantages of using titanium implants coated with nanostructured hydroxyapatite for the reconstruction of the orbital wall. Titanium implants, recognized for their durability and mechanical strength, when combined with the osteoconductive properties of hydroxyapatite, present a potentially synergistic solution. The purpose of this review was to critically analyze the recent literature and present the state of the art in orbital wall reconstruction using titanium implants coated with nanostructured hydroxyapatite. This review offers clinicians detailed insight into the benefits and potential drawbacks of using titanium implants coated with nanostructured hydroxyapatite for orbital wall reconstruction. The highlighted results advocate for its benefits in terms of osseointegration and provide a novel strategy for orbital reconstruction, though further studies are essential to establish long-term efficacy and address concerns.
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Affiliation(s)
- Victor A. Vasile
- Department of Ophthalmology, Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (V.A.V.)
- Department of Ophthalmology, Emergency University Hospital, 050098 Bucharest, Romania
| | - Ruxandra A. Pirvulescu
- Department of Ophthalmology, Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (V.A.V.)
- Department of Ophthalmology, Emergency University Hospital, 050098 Bucharest, Romania
| | - Raluca C. Iancu
- Department of Ophthalmology, Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (V.A.V.)
- Department of Ophthalmology, Emergency University Hospital, 050098 Bucharest, Romania
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore 168751, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- School of Chemical and Biological Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, 4056 Basel, Switzerland
| | - Aurelian M. Ghita
- Department of Ophthalmology, Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (V.A.V.)
- Department of Ophthalmology, Emergency University Hospital, 050098 Bucharest, Romania
| | - Diana Ionescu
- Department of ENT, Children’s Clinical Hospital “Dr. V. Gomoiu”, 022102 Bucharest, Romania
| | | | - Roxana M. Piticescu
- Nanostructured Materials Laboratory, National R&D Institute for Nonferrous and Rare Metals, 077145 Pantelimon, Romania
| | - Laura M. Cursaru
- Nanostructured Materials Laboratory, National R&D Institute for Nonferrous and Rare Metals, 077145 Pantelimon, Romania
| | - Alina Popa-Cherecheanu
- Department of Ophthalmology, Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania; (V.A.V.)
- Department of Ophthalmology, Emergency University Hospital, 050098 Bucharest, Romania
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Hagn G, Meier-Menches SM, Plessl-Walder G, Mitra G, Mohr T, Preindl K, Schlatter A, Schmidl D, Gerner C, Garhöfer G, Bileck A. Plasma Instead of Serum Avoids Critical Confounding of Clinical Metabolomics Studies by Platelets. J Proteome Res 2024. [PMID: 38520676 DOI: 10.1021/acs.jproteome.3c00761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2024]
Abstract
Metabolomics is an emerging and powerful bioanalytical method supporting clinical investigations. Serum and plasma are commonly used without rational prioritization. Serum is collected after blood coagulation, a complex biochemical process involving active platelet metabolism. This may affect the metabolome and increase the variance, as platelet counts and function may vary substantially in individuals. A multiomics approach systematically investigating the suitability of serum and plasma for clinical studies demonstrated that metabolites correlated well (n = 461, R2 = 0.991), whereas lipid mediators (n = 83, R2 = 0.906) and proteins (n = 322, R2 = 0.860) differed substantially between specimen. Independently, analysis of platelet releasates identified most biomolecules significantly enriched in serum compared to plasma. A prospective, randomized, controlled parallel group metabolomics trial with acetylsalicylic acid administered for 7 days demonstrated that the apparent drug effects significantly differ depending on the analyzed specimen. Only serum analyses of healthy individuals suggested a significant downregulation of TXB2 and 12-HETE, which were specifically formed during coagulation in vitro. Plasma analyses reliably identified acetylsalicylic acid effects on metabolites and lipids occurring in vivo such as an increase in serotonin, 15-deoxy-PGJ2 and sphingosine-1-phosphate and a decrease in polyunsaturated fatty acids. The present data suggest that plasma should be preferred above serum for clinical metabolomics studies as the serum metabolome may be substantially confounded by platelets.
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Affiliation(s)
- Gerhard Hagn
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
- Vienna Doctoral School in Chemistry (DoSChem), University of Vienna, Waehringer Str. 42, 1090 Vienna, Austria
| | - Samuel M Meier-Menches
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
- Joint Metabolome Facility, University and Medical University of Vienna, WaehringerStraße 38, 1090 Vienna, Austria
| | - Günter Plessl-Walder
- Joint Metabolome Facility, University and Medical University of Vienna, WaehringerStraße 38, 1090 Vienna, Austria
| | - Gaurav Mitra
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
- Joint Metabolome Facility, University and Medical University of Vienna, WaehringerStraße 38, 1090 Vienna, Austria
| | - Thomas Mohr
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
| | - Karin Preindl
- Joint Metabolome Facility, University and Medical University of Vienna, WaehringerStraße 38, 1090 Vienna, Austria
- Department of Laboratory Medicine, Medical University of Vienna, Waehringer Gürtel 18-20, 1090 Vienna, Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Christopher Gerner
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
- Joint Metabolome Facility, University and Medical University of Vienna, WaehringerStraße 38, 1090 Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Andrea Bileck
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
- Joint Metabolome Facility, University and Medical University of Vienna, WaehringerStraße 38, 1090 Vienna, Austria
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Schlatter A, Palkovits S, Ruiss M, Fisus AD, Hirnschall N, Schmidl D, Garhöfer G, Findl O. Repeatability of biometry in patients with meibomian gland dysfunction before and after vectored thermal pulsation therapy: A randomized, controlled trial. Acta Ophthalmol 2024; 102:e60-e68. [PMID: 37203877 DOI: 10.1111/aos.15711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 04/23/2023] [Accepted: 05/05/2023] [Indexed: 05/20/2023]
Abstract
PURPOSE To evaluate the effect of vectored thermal pulsation therapy (VTPT) on the repeatability of biometry readings of two different optical biometers in patients with meibomian gland dysfunction (MGD). METHODS Patients affected by MGD were included in this prospective, randomized, controlled, investigator-masked study. One eye was randomized to VTPT (LipiFlow®, Johnson & Johnson), and the contralateral eye served as a control. Three visits were scheduled at baseline, 2 weeks and 3 months after the treatment. The main outcome parameter of the study was the repeatability of three calculations of emmetropic intraocular lens power (EIOLP) at the 3 months visit as compared to baseline using an optical biometer (IOLMaster® 700, Carl Zeiss Meditec AG). Repeatability of different keratometry values obtained by the optical biometer and a Placido-disc topographer (MS-39®, CSO) served as secondary outcome parameters. RESULTS Twenty-nine patients were included in the final analysis. While tear film parameters improved in the study eyes, there were no significant differences regarding the repeatability of three EIOLP measurements between baseline and 3-months-visit in both eyes (p > 0.05) and keratometry measurements in both the optical biometer and the Placido-disc topographer. Remarkably, throughout all study visits, there were some outliers regarding the repeatability of measurements. CONCLUSION While both devices showed high repeatability regarding EIOLP and keratometry, future studies are needed to detect high-risk patients for poor repeatability.
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Affiliation(s)
- Andreas Schlatter
- VIROS - Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Stefan Palkovits
- VIROS - Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Manuel Ruiss
- VIROS - Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Andreea-Dana Fisus
- VIROS - Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Nino Hirnschall
- Department of Ophthalmology and Optometry, Kepler University Hospital GmbH, Linz, Austria
- Johannes Kepler University Linz, Medical Faculty, Linz, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Oliver Findl
- VIROS - Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
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Labetoulle M, Garhöfer G, Ismail D, Garrigue JS, Amrane M, Guillon M, Aragona P, Baudouin C. Review of clinical outcomes of a cationic emulsion tear substitute in patients with dry eye disease. Acta Ophthalmol 2024. [PMID: 38294079 DOI: 10.1111/aos.16629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 02/01/2024]
Abstract
First-line options for the treatment of dry eye disease (DED) rely on artificial tears (ATs), among which cationic emulsion (CE)-based ATs have been developed in order to mimic the healthy tear film for an improved restoration of the ocular surface homeostasis. In this review, we describe the outcomes reported in several studies, assessing the mode of action, ocular tolerance and clinical performance of a CE-based AT. Pilot studies have revealed that CE-based ATs can increase the volume and stability of the tear film while limiting its evaporation rate. Larger studies have demonstrated that CE-based ATs play a significant role in the improvement of both objective and subjective DED parameters, including superior efficacy on DED symptoms compared to several other available AT formulation types. Concomitantly, CE-based ATs have been shown to help patients to prevent or recover from corneal defects associated with refractive surgery. These positive outcomes on ocular surface epithelia are likely due to the combination of unique rheological behaviour and intrinsic anti-inflammatory properties. Based on all clinical findings, CE-based ATs represent a valuable treatment option for patients with various etiologies of DED including evaporative forms and would deserve evaluation of benefits in other surgical intervention types triggering DED.
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Affiliation(s)
- Marc Labetoulle
- Ophthalmology, South Paris University Hospital-APHP, Le Kremlin-Bicêtre, France
- IDMIT Infrastructure, Inserm, Cedex, France
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | | | | | | | - Pasquale Aragona
- Eye Clinic, Department of Biomedical Sciences, University of Messina, Messina, Italy
| | - Christophe Baudouin
- Department of Ophthalmology, Quinze-Vingts Hospital, IHU FOReSIGHT, Paris, France
- University Paris Saclay, Versailles Saint-Quentin en Yvelines, Paris, France
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Bostan M, Li C, Sim YC, Bujor I, Wong D, Tan B, Ismail MB, Garhöfer G, Tiu C, Pirvulescu R, Schmetterer L, Popa-Cherecheanu A, Chua J. Combining retinal structural and vascular measurements improves discriminative power for multiple sclerosis patients. Ann N Y Acad Sci 2023; 1529:72-83. [PMID: 37656135 DOI: 10.1111/nyas.15060] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Data on how retinal structural and vascular parameters jointly influence the diagnostic performance of detection of multiple sclerosis (MS) patients without optic neuritis (MSNON) are lacking. To investigate the diagnostic performance of structural and vascular changes to detect MSNON from controls, we performed a cross-sectional study of 76 eyes from 51 MS participants and 117 eyes from 71 healthy controls. Retinal macular ganglion cell complex (GCC), retinal nerve fiber layer (RNFL) thicknesses, and capillary densities from the superficial (SCP) and deep capillary plexuses (DCP) were obtained from the Cirrus AngioPlex. The best structural parameter for detecting MS was compensated RNFL from the optic nerve head (AUC = 0.85), followed by GCC from the macula (AUC = 0.79), while the best vascular parameter was the SCP (AUC = 0.66). Combining structural and vascular parameters improved the diagnostic performance for MS detection (AUC = 0.90; p<0.001). Including both structure and vasculature in the joint model considerably improved the discrimination between MSNON and normal controls compared to each parameter separately (p = 0.027). Combining optical coherence tomography (OCT)-derived structural metrics and vascular measurements from optical coherence tomography angiography (OCTA) improved the detection of MSNON. Further studies may be warranted to evaluate the clinical utility of OCT and OCTA parameters in the prediction of disease progression.
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Affiliation(s)
- Mihai Bostan
- Department of Ophthalmology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, Ophthalmology Emergency Hospital, Bucharest, Romania
| | - Chi Li
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- School of Computer Science and Engineering, Nanyang Technological University, Singapore
| | - Yin Ci Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Inna Bujor
- Department of Ophthalmology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Damon Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore
| | - Munirah Binte Ismail
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
| | - Cristina Tiu
- Department of Ophthalmology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Neurology, Emergency University Hospital, Bucharest, Romania
| | - Ruxandra Pirvulescu
- Department of Ophthalmology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, Emergency University Hospital, Bucharest, Romania
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Alina Popa-Cherecheanu
- Department of Ophthalmology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, Emergency University Hospital, Bucharest, Romania
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore
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Schmetterer L, Scholl H, Garhöfer G, Janeschitz-Kriegl L, Corvi F, Sadda SR, Medeiros FA. Endpoints for clinical trials in ophthalmology. Prog Retin Eye Res 2023; 97:101160. [PMID: 36599784 DOI: 10.1016/j.preteyeres.2022.101160] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 12/22/2022] [Accepted: 12/28/2022] [Indexed: 01/03/2023]
Abstract
With the identification of novel targets, the number of interventional clinical trials in ophthalmology has increased. Visual acuity has for a long time been considered the gold standard endpoint for clinical trials, but in the recent years it became evident that other endpoints are required for many indications including geographic atrophy and inherited retinal disease. In glaucoma the currently available drugs were approved based on their IOP lowering capacity. Some recent findings do, however, indicate that at the same level of IOP reduction, not all drugs have the same effect on visual field progression. For neuroprotection trials in glaucoma, novel surrogate endpoints are required, which may either include functional or structural parameters or a combination of both. A number of potential surrogate endpoints for ophthalmology clinical trials have been identified, but their validation is complicated and requires solid scientific evidence. In this article we summarize candidates for clinical endpoints in ophthalmology with a focus on retinal disease and glaucoma. Functional and structural biomarkers, as well as quality of life measures are discussed, and their potential to serve as endpoints in pivotal trials is critically evaluated.
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Affiliation(s)
- Leopold Schmetterer
- Singapore Eye Research Institute, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore; Academic Clinical Program, Duke-NUS Medical School, Singapore; School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore; Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria; Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria; Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland.
| | - Hendrik Scholl
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland; Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
| | - Lucas Janeschitz-Kriegl
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland; Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Federico Corvi
- Eye Clinic, Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Italy
| | - SriniVas R Sadda
- Doheny Eye Institute, Los Angeles, CA, USA; Department of Ophthalmology, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
| | - Felipe A Medeiros
- Vision, Imaging and Performance Laboratory, Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, USA
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8
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Lindner T, Schmidl D, Peschorn L, Pai V, Popa-Cherecheanu A, Chua J, Schmetterer L, Garhöfer G. Therapeutic Potential of Cannabinoids in Glaucoma. Pharmaceuticals (Basel) 2023; 16:1149. [PMID: 37631064 PMCID: PMC10460067 DOI: 10.3390/ph16081149] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 08/07/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
Glaucoma is a leading cause of irreversible blindness worldwide. To date, intraocular pressure (IOP) is the only modifiable risk factor in glaucoma treatment, but even in treated patients, the disease can progress. Cannabinoids, which have been known to lower IOP since the 1970s, have been shown to have beneficial effects in glaucoma patients beyond their IOP-lowering properties. In addition to the classical cannabinoid receptors CB1 and CB2, knowledge of non-classical cannabinoid receptors and the endocannabinoid system has increased in recent years. In particular, the CB2 receptor has been shown to mediate anti-inflammatory, anti-apoptotic, and neuroprotective properties, which may represent a promising therapeutic target for neuroprotection in glaucoma patients. Due to their vasodilatory effects, cannabinoids improve blood flow to the optic nerve head, which may suggest a vasoprotective potential and counteract the altered blood flow observed in glaucoma patients. The aim of this review was to assess the available evidence on the effects and therapeutic potential of cannabinoids in glaucoma patients. The pharmacological mechanisms underlying the effects of cannabinoids on IOP, neuroprotection, and ocular hemodynamics have been discussed.
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Affiliation(s)
- Theresa Lindner
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
| | - Laura Peschorn
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
| | - Viktoria Pai
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
| | - Alina Popa-Cherecheanu
- Department of Ophthalmology, Emergency University Hospital, 050098 Bucharest, Romania;
- Carol Davila University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore;
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore;
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Nanyang Technological University, Singapore 639798, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore 637459, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, 1090 Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, 4031 Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, 1090 Vienna, Austria; (T.L.); (D.S.); (L.P.); (V.P.); (L.S.)
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9
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Liu X, Jiang L, Ke M, Sigal IA, Chua J, Hoang QV, Chia AW, Najjar RP, Tan B, Cheong J, Bellemo V, Chong RS, Girard MJA, Ang M, Liu M, Garhöfer G, Barathi VA, Saw SM, Villiger M, Schmetterer L. Posterior scleral birefringence measured by triple-input polarization-sensitive imaging as a biomarker of myopia progression. Nat Biomed Eng 2023; 7:986-1000. [PMID: 37365268 PMCID: PMC10427432 DOI: 10.1038/s41551-023-01062-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 05/30/2023] [Indexed: 06/28/2023]
Abstract
In myopic eyes, pathological remodelling of collagen in the posterior sclera has mostly been observed ex vivo. Here we report the development of triple-input polarization-sensitive optical coherence tomography (OCT) for measuring posterior scleral birefringence. In guinea pigs and humans, the technique offers superior imaging sensitivities and accuracies than dual-input polarization-sensitive OCT. In 8-week-long studies with young guinea pigs, scleral birefringence was positively correlated with spherical equivalent refractive errors and predicted the onset of myopia. In a cross-sectional study involving adult individuals, scleral birefringence was associated with myopia status and negatively correlated with refractive errors. Triple-input polarization-sensitive OCT may help establish posterior scleral birefringence as a non-invasive biomarker for assessing the progression of myopia.
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Affiliation(s)
- Xinyu Liu
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore
| | - Liqin Jiang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Mengyuan Ke
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Ian A Sigal
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore
| | - Quan V Hoang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine National University of Singapore, Singapore, Singapore
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Audrey Wi Chia
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Raymond P Najjar
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine National University of Singapore, Singapore, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore
| | - Jocelyn Cheong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Valentina Bellemo
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Rachel S Chong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Michaël J A Girard
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Marcus Ang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Mengyang Liu
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Veluchamy A Barathi
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine National University of Singapore, Singapore, Singapore
- Translational Pre-Clinical Model Platform, Singapore Eye Research Institute, Singapore, Singapore
| | - Seang-Mei Saw
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- Saw Swee Hock School of Public Health, ,National University of Singapore, National University Health System, Singapore, Singapore
| | - Martin Villiger
- Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital, Boston, MA, USA
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.
- Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.
- SERI-NTU Advanced Ocular Engineering (STANCE) programme, Singapore, Singapore.
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore.
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland.
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.
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10
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Schlatter A, Hommer N, Kallab M, Stegmann H, Zeller K, Palkovits S, Findl O, Werkmeister RM, Schmetterer L, Garhöfer G, Schmidl D. Effect of Treatment with Topical Azithromycin or Oral Doxycycline on Tear Film Thickness in Patients with Meibomian Gland Dysfunction: A Randomized Controlled Trial. J Ocul Pharmacol Ther 2023. [PMID: 37327369 DOI: 10.1089/jop.2022.0186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023] Open
Abstract
Purpose: This prospective, randomized, observer-masked, parallel-group study aimed to compare the effect of topical azithromycin and oral doxycycline on tear film thickness (TFT) and signs and symptoms of ocular surface disease (OSD) in patients with meibomian gland dysfunction (MGD). Methods: Patients were randomized to either receive topical azithromycin or oral doxycycline. After a baseline visit, three follow-up visits at intervals of 2 weeks were scheduled. Main outcome of the study was change in TFT as measured with ultrahigh resolution optical coherence tomography. Results: Twenty patients were included in the analysis. TFT significantly increased in both groups (P = 0.028 vs. baseline) with no difference between the groups (P = 0.096). As secondary outcomes, ocular surface disease index (OSDI) score and composite signs of OSD significantly decreased in both groups (P = 0.023 for OSDI and P = 0.016 for OSD signs vs. baseline). While eye-related adverse events (AEs) occurred more frequently in the azithromycin group, systemic AEs were more common in the doxycycline group. Conclusions: Both treatments improved signs and symptoms of OSD in patients with MGD with no difference between the groups. Due to the higher frequency of systemic side effects of doxycycline, azithromycin eye drops seem to be an alternative with comparable efficacy. Clinical Trial Registration number: NCT03162497.
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Affiliation(s)
- Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- VIROS-Vienna Institute for Research in Ocular Surgery-Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Hannes Stegmann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria
| | - Kristina Zeller
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- VIROS-Vienna Institute for Research in Ocular Surgery-Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Stefan Palkovits
- VIROS-Vienna Institute for Research in Ocular Surgery-Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Oliver Findl
- VIROS-Vienna Institute for Research in Ocular Surgery-Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- School of Chemical and Biological Engineering, Nanyang Technological University, Singapore, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
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11
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Cherecheanu MP, Romanitan MO, Pirvulescu R, Iancu R, Garhöfer G, Iancu G, Cherecheanu AP, Zemba M, Vasile V, Simonov A, Branisteanu D. Uncommon association between vascular Ehlers–Danlos syndrome and ocular complications. Front Med (Lausanne) 2023; 10:1089652. [PMID: 37064021 PMCID: PMC10090385 DOI: 10.3389/fmed.2023.1089652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 03/07/2023] [Indexed: 03/30/2023] Open
Abstract
Ehlers–Danlos syndromes (EDS) represent a group of rare inherited disorders that affect connective tissues. There are 13 types of disease, most of them affecting joints or skin; symptoms usually include loose joints, joint pain, stretchy velvety skin, abnormal scar formation. However, the most serious type of disease is vascular EDS (vEDS), or EDS type 4 because patients may suffer vessels dissections or internal organs lesions, followed by bleeding, which endangers patient’s life, but also thromboembolic events. We present two clinical cases of vEDS managed in our clinic in 1 year distance. In both cases, patients were active young persons (in their thirties, and respectively, twenties), both with multiple non-traumatic vascular dissections, and severe ocular complications: arterio-venous fistula with massive exophthalmia, and central retinal artery occlusion, respectively. Both cases were challenging since the life of the patients were threatened by their condition. However, in both cases, prompt treatment and finding the right trigger of the ocular pathology and vascular injuries helped doctors to provide proper and prompt medical care, in order to prevent future similar events to happen and to preserve a good quality of life for these patients.
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Affiliation(s)
- Matei Popa Cherecheanu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Cardiovascular Surgery Clinic, Prof. Dr. Agrippa Ionescu Emergency Clinical Hospital, Bucharest, Romania
| | - Mihaela Oana Romanitan
- Department for Emergency Internal Medicine and Neurology, Stockholm South General Hospital, Stockholm, Sweden
- *Correspondence: Mihaela Oana Romanitan, ; Ruxandra Pirvulescu, ; ; Raluca Iancu,
| | - Ruxandra Pirvulescu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, University Emergency Hospital, Bucharest, Romania
- *Correspondence: Mihaela Oana Romanitan, ; Ruxandra Pirvulescu, ; ; Raluca Iancu,
| | - Raluca Iancu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, University Emergency Hospital, Bucharest, Romania
- *Correspondence: Mihaela Oana Romanitan, ; Ruxandra Pirvulescu, ; ; Raluca Iancu,
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - George Iancu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Filantropia Clinical Hospital, Bucharest, Romania
| | - Alina Popa Cherecheanu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, University Emergency Hospital, Bucharest, Romania
| | - Mihail Zemba
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, Clinical Military Emergency Hospital, Bucharest, Romania
| | - Victor Vasile
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Andrei Simonov
- Department of Interventional Radiology, University Emergency Hospital, Bucharest, Romania
| | - Daniel Branisteanu
- Department of Ophthalmology, University of Medicine and Pharmacy Grigore T. Popa Iasi, Iasi, Romania
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12
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Nadvornik C, Kallab M, Hommer N, Schlatter A, Stengel T, Garhöfer G, Zeitlinger M, Eberl S, Klymiuk I, Trajanoski S, Nehr M, Makristathis A, Schmidl D, Nussbaumer-Proell A. Effect of Antibiotic Eye Drops on the Nasal Microbiome in Healthy Subjects—A Pilot Study. Antibiotics (Basel) 2023; 12:antibiotics12030517. [PMID: 36978384 PMCID: PMC10044076 DOI: 10.3390/antibiotics12030517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023] Open
Abstract
Background: Antibiotic eye drops are frequently used in clinical practice. Due to the anatomical connection via the nasolacrimal duct, it seems possible that they have an influence on the nasal/pharyngeal microbiome. This was investigated by using two different commonly used antibiotic eye drops. Methods: 20 subjects were randomized to four groups of five subjects receiving eye drops containing gentamicin, ciprofloxacin, or, as controls, unpreserved povidone or benzalkonium chloride-preserved povidone. Nasal and pharyngeal swabs were performed before and after the instillation period. Swabs were analyzed by Illumina next-generation sequencing (NGS)-based 16S rRNA analysis. Bacterial culture was performed on solid media, and bacterial isolates were identified to the species level by MALDI-TOF MS. Species-dependent antimicrobial susceptibility testing was performed using single isolates and pools of isolates. Results: Bacterial richness in the nose increased numerically from 163 ± 30 to 243 ± 100 OTUs (gentamicin) and from 114 ± 17 to 144 ± 45 OTUs (ciprofloxacin). Phylogenetic diversity index (pd) of different bacterial strains in the nasal microbiome increased from 12.4 ± 1.0 to 16.9 ± 5.6 pd (gentamicin) and from 10.2 ± 1.4 to 11.8 ± 3.1 pd (ciprofloxacin). Unpreserved povidone eye drops resulted in minimal changes in bacterial counts. Preservative-containing povidone eye drops resulted in no change. A minor increase (1–2-fold) in the minimal inhibitory concentration (MIC) was observed in single streptococcal isolates. Conclusions: Antibiotic eye drops could affect the nasal microbiome. After an instillation period of seven days, an increase in the diversity and richness of bacterial strains in the nasal microbiome was observed.
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Affiliation(s)
- Clemens Nadvornik
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Theresa Stengel
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Markus Zeitlinger
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Sabine Eberl
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Ingeborg Klymiuk
- Division of Cell Biology, Histology and Embryology, Gottfried Schatz Research Center, Medical University of Graz, 8036 Graz, Austria
| | - Slave Trajanoski
- Core Facility Computational Bioanalytics, Center for Medical Research, Medical University of Graz, 8036 Graz, Austria
| | - Marion Nehr
- Department of Clinical Microbiology, Clinical Institute of Laboratory Medicine, Medical University of Vienna, 1090 Vienna, Austria
| | - Athanasios Makristathis
- Department of Clinical Microbiology, Clinical Institute of Laboratory Medicine, Medical University of Vienna, 1090 Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Alina Nussbaumer-Proell
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
- Correspondence: ; Tel.: +43-(0)1-40400-29810
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13
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Kovarik JJ, Bileck A, Hagn G, Meier-Menches SM, Frey T, Kaempf A, Hollenstein M, Shoumariyeh T, Skos L, Reiter B, Gerner MC, Spannbauer A, Hasimbegovic E, Schmidl D, Garhöfer G, Gyöngyösi M, Schmetterer KG, Gerner C. A multi-omics based anti-inflammatory immune signature characterizes Long COVID Syndrome. iScience 2022; 26:105717. [PMCID: PMC9719844 DOI: 10.1016/j.isci.2022.105717] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/13/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
To investigate Long COVID Syndrome (LCS) pathophysiology, we performed an exploratory study with blood plasma derived from three groups: 1) healthy vaccinated individuals without SARS-CoV-2 exposure; 2) asymptomatic recovered patients at least three months after SARS-CoV-2 infection and; 3) symptomatic patients at least 3 months after SARS-CoV-2 infection with chronic fatigue syndrome or similar symptoms, here designated as Long COVID Syndrome (LCS) patients. Multiplex cytokine profiling indicated slightly elevated pro-inflammatory cytokine levels in recovered individuals in contrast to LCS patients. Plasma proteomics demonstrated low levels of acute phase proteins and macrophage-derived secreted proteins in LCS. High levels of anti-inflammatory oxylipins including omega-3 fatty acids in LCS were detected by eicosadomics, whereas targeted metabolic profiling indicated high levels of anti-inflammatory osmolytes taurine and hypaphorine, but low amino acid and triglyceride levels and deregulated acylcarnithines. A model considering alternatively polarized macrophages as a major contributor for these molecular alterations is presented.
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Affiliation(s)
- Johannes J. Kovarik
- Department of Internal Medicine III, Clinical Division of Nephrology and Dialysis, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria
| | - Andrea Bileck
- Joint Metabolome Facility, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria,Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
| | - Gerhard Hagn
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
| | - Samuel M. Meier-Menches
- Joint Metabolome Facility, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria,Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
| | - Tobias Frey
- Department of Laboratory Medicine, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria
| | - Anna Kaempf
- Department of Laboratory Medicine, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria
| | - Marlene Hollenstein
- Department of Laboratory Medicine, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria
| | - Tarik Shoumariyeh
- Department of Internal Medicine III, Clinical Division of Nephrology and Dialysis, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria
| | - Lukas Skos
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria
| | - Birgit Reiter
- Department of Laboratory Medicine, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria
| | - Marlene C. Gerner
- Division of Biomedical Science, University of Applied Sciences FH Campus Wien, Vienna, Austria
| | - Andreas Spannbauer
- Department of Medicine II, Division of Cardiology, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria
| | - Ena Hasimbegovic
- Department of Medicine II, Division of Cardiology, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Mariann Gyöngyösi
- Department of Medicine II, Division of Cardiology, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria,Corresponding author (Lead Contact)
| | - Klaus G. Schmetterer
- Department of Laboratory Medicine, Medical University of Vienna, Waehringer Gürtel 18-20, Vienna, Austria,Corresponding author (Lead Contact)
| | - Christopher Gerner
- Joint Metabolome Facility, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria,Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria,Corresponding author (Lead Contact)
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14
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Garhöfer G. Development of neuroprotective agents – Possible endpoints and regulatory considerations. Acta Ophthalmol 2022. [DOI: 10.1111/j.1755-3768.2022.15343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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15
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Hommer N, Kallab M, Schlatter A, Howorka K, Werkmeister RM, Schmidl D, Schmetterer L, Garhöfer G. Retinal Oxygen Metabolism in Patients With Type 2 Diabetes and Different Stages of Diabetic Retinopathy. Diabetes 2022; 71:2677-2684. [PMID: 36107468 PMCID: PMC9862478 DOI: 10.2337/db22-0219] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 09/11/2022] [Indexed: 02/05/2023]
Abstract
The aim of this cross-sectional study was to assess retinal oxygen metabolism in patients with type 2 diabetes and different stages of nonproliferative diabetic retinopathy (DR) (n = 67) compared with healthy control subjects (n = 20). Thirty-four patients had no DR, 15 had mild DR, and 18 had moderate to severe DR. Retinal oxygen saturation in arteries and veins was measured using the oxygen module of a retinal vessel analyzer. Total retinal blood flow (TRBF) was measured using a custom-built Doppler optical coherence tomography system. Retinal oxygen extraction was calculated from retinal oxygen saturation and TRBF. Arteriovenous difference in oxygen saturation was highest in healthy subjects (34.9 ± 7.5%), followed by patients with no DR (32.5 ± 6.3%) and moderate to severe DR (30.3 ± 6.5%). The lowest values were found in patients with mild DR (27.3 ± 8.0%, P = 0.010 vs. healthy subjects). TRBF tended to be higher in patients with no DR (40.1 ± 9.2 μL/min) and mild DR (41.8 ± 15.0 μL/min) than in healthy subjects (37.2 ± 5.7 μL/min) and patients with moderate to severe DR (34.6 ± 10.4 μL/min). Retinal oxygen extraction was the highest in healthy subjects (2.24 ± 0.57 μL O2/min), followed by patients with no DR (2.14 ± 0.6 μL O2/min), mild DR (1.90 ± 0.77 μL O2/min), and moderate to severe DR (1.78 ± 0.57 μL O2/min, P = 0.040 vs. healthy subjects). These results indicate that retinal oxygen metabolism is altered in patients with type 2 diabetes. Furthermore, retinal oxygen extraction decreases with increasing severity of DR.
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Affiliation(s)
- Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Kinga Howorka
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore
- Singapore Eye Research Institute-Nanyang Technical University Advanced Ocular Engineering (STANCE), Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
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16
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Chua J, Li C, Ho LKH, Wong D, Tan B, Yao X, Gan A, Schwarzhans F, Garhöfer G, Sng CCA, Hilal S, Venketasubramanian N, Cheung CY, Fischer G, Vass C, Wong TY, Chen CLH, Schmetterer L. A multi-regression framework to improve diagnostic ability of optical coherence tomography retinal biomarkers to discriminate mild cognitive impairment and Alzheimer’s disease. Alzheimers Res Ther 2022; 14:41. [PMID: 35272711 PMCID: PMC8908577 DOI: 10.1186/s13195-022-00982-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 02/23/2022] [Indexed: 11/24/2022]
Abstract
Background Diagnostic performance of optical coherence tomography (OCT) to detect Alzheimer’s disease (AD) and mild cognitive impairment (MCI) remains limited. We assessed whether compensating the circumpapillary retinal nerve fiber layer (cpRNFL) thickness for multiple demographic and anatomical factors as well as the combination of macular layers improves the detection of MCI and AD. Methods This cross-sectional study of 62 AD (n = 92 eyes), 108 MCI (n = 158 eyes), and 55 cognitively normal control (n = 86 eyes) participants. Macular ganglion cell complex (mGCC) thickness was extracted. Circumpapillary retinal nerve fiber layer (cpRNFL) measurement was compensated for several ocular factors. Thickness measurements and their corresponding areas under the receiver operating characteristic curves (AUCs) were compared between the groups. The main outcome measure was OCT thickness measurements. Results Participants with MCI/AD showed significantly thinner measured and compensated cpRNFL, mGCC, and altered retinal vessel density (p < 0.05). Compensated RNFL outperformed measured RNFL for discrimination of MCI/AD (AUC = 0.74 vs 0.69; p = 0.026). Combining macular and compensated cpRNFL parameters provided the best detection of MCI/AD (AUC = 0.80 vs 0.69; p < 0.001). Conclusions and relevance Accounting for interindividual variations of ocular anatomical features in cpRNFL measurements and incorporating macular information may improve the identification of high-risk individuals with early cognitive impairment. Supplementary Information The online version contains supplementary material available at 10.1186/s13195-022-00982-0.
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Lindner T, Hommer N, Kallab M, Schlatter A, Nadvornik C, Janku P, Kauer V, Rumpf B, Haslacher H, Garhöfer G, Schmidl D. Retinal blood flow and oxygen saturation in patients previously infected with
COVID
‐19. Acta Ophthalmol 2022. [DOI: 10.1111/j.1755-3768.2022.0088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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18
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Hommer N, Kallab M, Schlatter A, Janku P, Werkmeister RM, Howorka K, Schmidl D, Schmetterer L, Garhöfer G. Neuro-vascular coupling and heart rate variability in patients with type II diabetes at different stages of diabetic retinopathy. Front Med (Lausanne) 2022; 9:1025853. [PMID: 36438055 PMCID: PMC9684184 DOI: 10.3389/fmed.2022.1025853] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 10/26/2022] [Indexed: 11/11/2022] Open
Abstract
Aims/Hypothesis There is evidence that diabetes is accompanied by a break-down of functional hyperemia, an intrinsic mechanism of neural tissues to adapt blood flow to changing metabolic demands. However, to what extent functional hyperemia is altered in different stages of diabetic retinopathy (DR) in patients with type II diabetes is largely unknown. The current study set out to investigate flicker-induced retinal blood flow changes in patients with type II diabetes at different stages of DR. Materials and methods A total of 76 subjects were included in the present parallel-group study, of which 56 had diabetes with either no DR or different stages of non-proliferative DR (n = 29 no DR, 12 mild DR, 15 moderate to severe DR). In addition, 20 healthy subjects were included as controls. Retinal blood flow was assessed before and during visual stimulation using a combined measurement of retinal vessel calibers and blood velocity by the means of Doppler optical coherence tomography (OCT). To measure systemic autonomic nervous system function, heart rate variability (HRV) was assessed using a short-term orthostatic challenge test. Results In healthy controls, retinal blood flow increased by 40.4 ± 27.2% during flicker stimulation. Flicker responses in patients with DR were significantly decreased depending on the stage of the disease (no DR 37.7 ± 26.0%, mild DR 26.2 ± 28.2%, moderate to severe DR 22.3 ± 13.9%; p = 0.035, ANOVA). When assessing systemic autonomous neural function using HRV, normalized low frequency (LF) spectral power showed a significantly different response to the orthostatic maneuver in diabetic patients compared to healthy controls (p < 0.001). Conclusion/Interpretation Our study indicates that flicker induced hyperemia is reduced in patients with DR compared to healthy subjects. Further, this impairment is more pronounced with increasing severity of DR. Further studies are needed to elucidate mechanisms behind the reduced hyperemic response in patients with type II diabetes. Clinical trial registration [https://clinicaltrials.gov/], identifier [NCT03 552562].
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Affiliation(s)
- Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- Hanusch Hospital, Karl Landsteiner Institute, Vienna, Austria
- Hanusch Hospital, Vienna Institute for Research in Ocular Surgery, Vienna, Austria
| | - Patrick Janku
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Kinga Howorka
- Metabolic Competence Center, Medical University of Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
- Institute of Clinical and Experimental Ophthalmology, Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- *Correspondence: Gerhard Garhöfer,
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19
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Hommer N, Kallab M, Sim YC, Lee AX, Chua J, Tan B, Schlatter A, Werkmeister RM, Schmidl D, Schmetterer L, Garhöfer G. Effect of hyperoxia and hypoxia on retinal vascular parameters assessed with optical coherence tomography angiography. Acta Ophthalmol 2022; 100:e1272-e1279. [PMID: 34881512 DOI: 10.1111/aos.15077] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 10/20/2021] [Accepted: 11/29/2021] [Indexed: 01/05/2023]
Abstract
PURPOSE To investigate the response of the superficial and deep capillary plexuses to hyperoxia and hypoxia using optical coherence tomography angiography (OCT-A) and retinal vessel analyzer. METHODS Twenty-four healthy volunteers participated in this randomized, double-masked, cross-over study. For each subject, two study days were scheduled: on one study day, hyperoxia was induced by breathing 100% oxygen whereas on the other study day, hypoxia was induced by breathing a mixture of 88% nitrogen and 12% oxygen. Perfusion density was calculated in the superficial vascular plexus (SVP) and the deep capillary plexus (DCP), using OCT-A before (normal breathing) and during breathing of the gas mixtures. Retinal vessel calibres in major retinal vessels were measured using a dynamic vessel analyzer. RESULTS During 100% oxygen breathing, a significant decrease in DCP perfusion density from 41.7 ± 2.4 a.u to 35.6 ± 3.1 a.u. (p < 0.001) was observed, which was accompanied by a significant decrease in vessel diameters in major retinal arteries and veins (p < 0.001 each). No significant change in perfusion density in the SVP occurred (p = 0.33). In contrast, during hypoxia, perfusion density in the SVP significantly increased from 34.4 ± 3.0 a.u. to 37.1 ± 2.2 a.u. (p < 0.001), while it remained stable in the DCP (p = 0.25). A significant increase in retinal vessel diameters was found (p < 0.01). Systemic oxygen saturation correlated negatively with perfusion density in the SVP and the DCP and retinal vessel diameters (p < 0.005 each). CONCLUSION Our results show that systemic hyperoxia induces a significant decrease in vessel density in the DCP, while hypoxia leads to increased vessel density limited to the SVP. These results indicate that the retinal circulation shows the ability to adapt its blood flow to metabolic changes with high local resolution dependent on the capillary plexus.
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Affiliation(s)
- Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Yin Ci Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Ashe Xy Lee
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,VIROS - Vienna Institute for Research in Ocular Surgery - Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Institute of Clinical and Experimental Ophthalmology, Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
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20
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Chua J, Zhang Z, Wong D, Tan B, Kulantayan B, Sng CCA, Hilal S, Venketasubramanian N, Tan BY, Cheung CY, Garhöfer G, Popa-Cherecheanu A, Wong TY, Chen CLH, Schmetterer L. Age-Related Eye Diseases in Individuals With Mild Cognitive Impairment and Alzheimer's Disease. Front Aging Neurosci 2022; 14:933853. [PMID: 35912080 PMCID: PMC9329945 DOI: 10.3389/fnagi.2022.933853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction Alzheimer's disease (AD) and age-related eye diseases pose an increasing burden as the world's population ages. However, there is limited understanding on the association of AD/cognitive impairment, no dementia (CIND) with age-related eye diseases. Methods In this cross-sectional, memory clinic-based study of multiethnic Asians aged 50 and above, participants were diagnosed as AD (n = 216), cognitive impairment, no dementia (CIND) (n = 252), and no cognitive impairment (NCI) (n = 124) according to internationally accepted criteria. Retinal photographs were graded for the presence of age-related macular degeneration (AMD) and diabetic retinopathy (DR) using standard grading systems. Multivariable-adjusted logistic regression models were used to determine the associations between neurological diagnosis and odds of having eye diseases. Results Over half of the adults had at least one eye disease, with AMD being the most common (60.1%; n = 356), followed by DR (8.4%; n = 50). After controlling for age, sex, race, educational level, and marital status, persons with AD were more likely to have moderate DR or worse (OR = 2.95, 95% CI = 1.15–7.60) compared with NCI. In the fully adjusted model, the neurological diagnosis was not associated with AMD (OR = 0.75, 95% CI = 0.45–1.24). Conclusion Patients with AD have an increased odds of having moderate DR or worse, which suggests that these vulnerable individuals may benefit from specific social support and screening for eye diseases.
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Affiliation(s)
- Jacqueline Chua
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
| | - Zheting Zhang
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Damon Wong
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Bingyao Tan
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Bhavani Kulantayan
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Chelvin C. A. Sng
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Department of Ophthalmology, National University of Singapore, Singapore, Singapore
| | - Saima Hilal
- Departments of Pharmacology and Psychological Medicine, Memory Aging and Cognition Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore, Singapore
| | - Narayanaswamy Venketasubramanian
- Departments of Pharmacology and Psychological Medicine, Memory Aging and Cognition Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Raffles Neuroscience Centre, Raffles Hospital, Singapore, Singapore
| | | | - Carol Y. Cheung
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
| | - Alina Popa-Cherecheanu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, Emergency University Hospital, Bucharest, Romania
| | - Tien Yin Wong
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
| | - Christopher Li-Hsian Chen
- Departments of Pharmacology and Psychological Medicine, Memory Aging and Cognition Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Leopold Schmetterer
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
- *Correspondence: Leopold Schmetterer
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21
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Sacu S, Eibenberger K, Schmidl D, Rezar-Dreindl S, Garhöfer G, Brugger J, Buehl W, Schmetterer L, Schmidt-Erfurth U. Retinal oxygen saturation, vessel diameter and flicker response in eyes with specific subtypes of neovascular age-related macular degeneration during aflibercept treatment. PLoS One 2022; 17:e0271166. [PMID: 35819932 PMCID: PMC9275690 DOI: 10.1371/journal.pone.0271166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/22/2022] [Indexed: 12/04/2022] Open
Abstract
Purpose To evaluate the effect of intravitreal aflibercept monotherapy on arterial and venous oxygen saturation, retinal vessel diameter and flicker response in patients with newly diagnosed specific subtypes of exudative maculopathy. Methods This prospective study included forty-four eyes of 44 patients with treatment-naïve polypoidal choroidal vasculopathy (PCV, n = 12), hemorrhagic choroidal neovascularization (hCNV, n = 12), pigment epithelium detachment (PED, n = 9) and type 3 MNV (RAP, n = 11). All patients received three initial aflibercept 2mg/0.05ml injections (Eylea®) in monthly intervals (loading phase) and were subsequently treated until month 12. Measurements of arterial and venous oxygen saturation, vessel diameters and flicker response were performed using the Dynamic Vessel Analyzer (DVA; IMEDOS, Jena, Germany). Statistical analysis was performed on the total population at baseline, after loading dose and at the last follow-up visit. Results The arterial oxygen saturation was 94.01±2.14% and showed no change after loading dose (93.94±2.88%, p = 0.4; estimated difference [confidence interval] -0.38 [-1.24; 0.48]) and at the last visit (95.48±1.90%; p = 0.1; -1.29 [-0.34; 2.91]). The venous oxygenation during treatment was 78.49±6.93% at baseline, 80.94±7.71% after 3-monthly injections (p = 0.7; -0.43 [-2.72; 1.86]) and 80.56±7.33% at month 12 (p = 0.5; 1.07 [-2.10; 4.24). The arterial and venous vessel diameters were 94±22μm and 131±19μm at baseline, and remained unchanged following aflibercept loading dose and at the last follow-up visit (p-value: p = 0.5; 2.30 [-5.00; 9.59] p = 0.8; 0.59 [-3.17; 4.34]). During stimulation with flicker light, arterial diameter changed by +1.24±4.93% at baseline and remained stable at month 3 (+2.70±5.95%; p = 0.5; 1.43 [-2.54; 5.41]) while the change in venous diameter during flicker stimulation was +4.52±4.45% at baseline and +4.13±3.65% after loading dose (p = 0.4, 5.18 [1.73; 8.63]). Conclusion During intravitreal aflibercept treatment oxygen saturation, vessel diameter and flicker response did not change in the total population of patients with specific subtypes of exudative maculopathy.
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Affiliation(s)
- Stefan Sacu
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
- * E-mail:
| | | | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Jonas Brugger
- Department of Medical Statistics, Medical University of Vienna, Vienna, Austria
| | - Wolf Buehl
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Singapore Eye Research Institute, Singapore, Singapore
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22
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Chua J, Bostan M, Li C, Sim YC, Bujor I, Wong D, Tan B, Yao X, Schwarzhans F, Garhöfer G, Fischer G, Vass C, Tiu C, Pirvulescu R, Popa-Cherecheanu A, Schmetterer L. A multi-regression approach to improve optical coherence tomography diagnostic accuracy in multiple sclerosis patients without previous optic neuritis. Neuroimage Clin 2022; 34:103010. [PMID: 35447469 PMCID: PMC9043868 DOI: 10.1016/j.nicl.2022.103010] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 04/12/2022] [Accepted: 04/12/2022] [Indexed: 01/19/2023]
Abstract
OCT diagnostics for MS improved after combining macular data with compensated peripapillary RNFL.
Background Optical coherence tomography (OCT) is a retinal imaging system that may improve the diagnosis of multiple sclerosis (MS) persons, but the evidence is currently equivocal. To assess whether compensating the peripapillary retinal nerve fiber layer (pRNFL) thickness for ocular anatomical features as well as the combination with macular layers can improve the capability of OCT in differentiating non-optic neuritis eyes of relapsing-remitting MS patients from healthy controls. Methods 74 MS participants (n = 129 eyes) and 84 age- and sex-matched healthy controls (n = 149 eyes) were enrolled. Macular ganglion cell complex (mGCC) thickness was extracted and pRNFL measurement was compensated for ocular anatomical factors. Thickness measurements and their corresponding areas under the receiver operating characteristic curves (AUCs) were compared between groups. Results Participants with MS showed significantly thinner mGCC, measured and compensated pRNFL (p ≤ 0.026). Compensated pRNFL achieved better performance than measured pRNFL for MS differentiation (AUC, 0.75 vs 0.80; p = 0.020). Combining macular and compensated pRNFL parameters provided the best discrimination of MS (AUC = 0.85 vs 0.75; p < 0.001), translating to an average improvement in sensitivity of 24 percent for differentiation of MS individuals. Conclusion The capability of OCT in MS differentiation is made more robust by accounting OCT scans for individual anatomical differences and incorporating information from both optic disc and macular regions, representing markers of axonal damage and neuronal injury, respectively.
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Affiliation(s)
- Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
| | - Mihai Bostan
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Ophthalmology Emergency Hospital, Bucharest, Romania
| | - Chi Li
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
| | - Yin Ci Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
| | - Inna Bujor
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Damon Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore; School of Chemical and Biological Engineering, Nanyang Technological University, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore; School of Chemical and Biological Engineering, Nanyang Technological University, Singapore
| | - Xinwen Yao
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore; School of Chemical and Biological Engineering, Nanyang Technological University, Singapore
| | - Florian Schwarzhans
- Center for Medical Statistics Informatics and Intelligent Systems, Section for Medical Information Management, Medical University Vienna, Vienna, Austria; Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
| | - Georg Fischer
- Center for Medical Statistics Informatics and Intelligent Systems, Section for Medical Information Management, Medical University Vienna, Vienna, Austria
| | - Clemens Vass
- Department of Ophthalmology and Optometry, Medical University Vienna, Vienna, Austria
| | - Cristina Tiu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Emergency University Hospital, Department of Neurology, Bucharest, Romania
| | - Ruxandra Pirvulescu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Emergency University Hospital, Department of Ophthalmology, Bucharest, Romania
| | - Alina Popa-Cherecheanu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Emergency University Hospital, Department of Ophthalmology, Bucharest, Romania.
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Singapore; SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore; School of Chemical and Biological Engineering, Nanyang Technological University, Singapore; Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria; Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria; Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland.
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23
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Calzetti G, Mursch‐Edlmayr AS, Bata AM, Ungaro N, Mora P, Chua J, Schmidl D, Bolz M, Garhöfer G, Gandolfi S, Schmetterer L, Wong D. Measuring optic nerve head perfusion to monitor glaucoma: a study on structure-function relationships using laser speckle flowgraphy. Acta Ophthalmol 2022; 100:e181-e191. [PMID: 33880888 DOI: 10.1111/aos.14862] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 02/21/2021] [Accepted: 03/16/2021] [Indexed: 12/31/2022]
Abstract
PURPOSE We aimed to describe the global and localized correlations among visual field (VF) sensitivity, optic nerve head (ONH) perfusion measured by laser speckle flowgraphy (LSFG) and neural structure measured by optical coherence tomography (OCT) in open-angle glaucoma (OAG) and to compare the floor effect for LSFG and OCT. METHODS Cross-sectional, multicenter study including one eye each from fifty OAG patients (mean age 69.3 years; average VF mean deviation, MD, -8.5 dB, range -25.17 to 0.85 dB) and fifty-one controls. Patients underwent SITA standard 24-2 automated perimetry and measurement of ONH perfusion, peripapillary retinal nerve fibre layer thickness (RNFLT) and macular ganglion cell-inner plexiform layer thickness (GCIPLT). We tested the presence of a significant change (breakpoint) in the correlation slope with VF sensitivity to assess floor effect. RESULTS The correlation between the LSFG parameter Mean All (MA) of the global disc area and MD (r = 0.56, p < 0.001) did not show a breakpoint, in contrast to the correlations between MD and OCT global parameters, which showed breakpoints at -8.53 and -4.05 dB for RNFLT and GCIPLT, respectively. Global and localized correlations with VF sensitivity were stronger for LSFG compared to OCT. In particular, LSFG outperformed OCT in the correlation with the central VF sector (r = 0.50, p < 0.001 and r = 0.06, p = 0.67 for MA and RNFLT, respectively). CONCLUSION The global and sectoral correlations with VF sensitivity and the favourable floor effect compared to OCT indicate LSFG as a promising tool to monitor progression particularly in late-stage glaucoma. Further longitudinal studies are warranted.
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Affiliation(s)
- Giacomo Calzetti
- Department of Ophthalmology University Hospital of Parma Parma Italy
- Institute of Molecular and Clinical Ophthalmology Basel Basel Switzerland
| | | | - Ahmed M. Bata
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Vienna Health Association Kaiser Franz Josef (Favoriten) Hospital Vienna Austria
| | - Nicola Ungaro
- Department of Ophthalmology University Hospital of Parma Parma Italy
| | - Paolo Mora
- Department of Ophthalmology University Hospital of Parma Parma Italy
| | - Jacqueline Chua
- Singapore Eye Research Institute Singapore National Eye Centre Singapore Singapore
- Academic Clinical Program Duke‐NUS Medical School Singapore Singapore
| | - Doreen Schmidl
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Matthias Bolz
- Department of Ophthalmology Kepler University Clinic Johannes Kepler University Linz Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Stefano Gandolfi
- Department of Ophthalmology University Hospital of Parma Parma Italy
| | - Leopold Schmetterer
- Institute of Molecular and Clinical Ophthalmology Basel Basel Switzerland
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Singapore Eye Research Institute Singapore National Eye Centre Singapore Singapore
- Academic Clinical Program Duke‐NUS Medical School Singapore Singapore
- School of Chemical and Biomedical Engineering Nanyang Technological University Singapore Singapore
| | - Damon Wong
- Singapore Eye Research Institute Singapore National Eye Centre Singapore Singapore
- SERI‐NTU Advanced Ocular Engineering (STANCE) Singapore Singapore
- NTU Institute of Health Technologies Singapore Singapore
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24
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Baumann B, Merkle CW, Augustin M, Glösmann M, Garhöfer G. Pulsatile tissue deformation dynamics of the murine retina and choroid mapped by 4D optical coherence tomography. Biomed Opt Express 2022; 13:647-661. [PMID: 35284183 PMCID: PMC8884196 DOI: 10.1364/boe.445093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/20/2021] [Accepted: 12/28/2021] [Indexed: 05/11/2023]
Abstract
Irregular ocular pulsatility and altered mechanical tissue properties are associated with some of the most sight-threatening eye diseases. Here we present 4D optical coherence tomography (OCT) for the quantitative assessment and depth-resolved mapping of pulsatile dynamics in the murine retina and choroid. Through a pixel-wise analysis of phase changes of the complex OCT signal, we reveal spatiotemporal displacement characteristics across repeated frame acquisitions. We demonstrate in vivo fundus elastography (FUEL) imaging in wildtype mouse retinas and in a mouse model of retinal neovascularization and uncover subtle structural deformations related to ocular pulsation. Our data in mouse eyes hold promise for a powerful retinal elastography technique that may enable a new paradigm of OCT-based measurements and image contrast.
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Affiliation(s)
- Bernhard Baumann
- Center for Medical Physics and Biomedical
Engineering, Medical University of Vienna,
Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Conrad W. Merkle
- Center for Medical Physics and Biomedical
Engineering, Medical University of Vienna,
Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Marco Augustin
- Center for Medical Physics and Biomedical
Engineering, Medical University of Vienna,
Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Martin Glösmann
- Core Facility for Research and Technology,
University of Veterinary Medicine Vienna,
Veterinärplatz 1, 1210 Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology,
Medical University of Vienna, Währinger
Gürtel 18-20, 1090 Vienna, Austria
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Brunmair J, Bileck A, Schmidl D, Hagn G, Meier-Menches SM, Hommer N, Schlatter A, Gerner C, Garhöfer G. Metabolic phenotyping of tear fluid as a prognostic tool for personalised medicine exemplified by T2DM patients. EPMA J 2022; 13:107-123. [PMID: 35265228 PMCID: PMC8897537 DOI: 10.1007/s13167-022-00272-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 01/17/2022] [Indexed: 12/18/2022]
Abstract
Background/aims Concerning healthcare approaches, a paradigm change from reactive medicine to predictive approaches, targeted prevention, and personalisation of medical services is highly desirable. This raises demand for biomarker signatures that support the prediction and diagnosis of diseases, as well as monitoring strategies regarding therapeutic efficacy and supporting individualised treatments. New methodological developments should preferably rely on non-invasively sampled biofluids like sweat and tears in order to provide optimal compliance, reduce costs, and ensure availability of the biomaterial. Here, we have thus investigated the metabolic composition of human tears in comparison to finger sweat in order to find biofluid-specific marker molecules derived from distinct secretory glands. The comprehensive investigation of numerous biofluids may lead to the identification of novel biomarker signatures. Moreover, tear fluid analysis may not only provide insight into eye pathologies but may also be relevant for the prediction and monitoring of disease progression and/ or treatment of systemic disorders such as type 2 diabetes mellitus. Methods Sweat and tear fluid were sampled from 20 healthy volunteers using filter paper and commercially available Schirmer strips, respectively. Finger sweat analysis has already been successfully established in our laboratory. In this study, we set up and evaluated methods for tear fluid extraction and analysis using high-resolution mass spectrometry hyphenated with liquid chromatography, using optimised gradients each for metabolites and eicosanoids. Sweat and tears were systematically compared using statistical analysis. As second approach, we performed a clinical pilot study with 8 diabetic patients and compared them to 19 healthy subjects. Results Tear fluid was found to be a rich source for metabolic phenotyping. Remarkably, several molecules previously identified by us in sweat were found significantly enriched in tear fluid, including creatine or taurine. Furthermore, other metabolites such as kahweol and various eicosanoids were exclusively detectable in tears, demonstrating the orthogonal power for biofluid analysis in order to gain information on individual health states. The clinical pilot study revealed that many endogenous metabolites that have previously been linked to type 2 diabetes such as carnitine, tyrosine, uric acid, and valine were indeed found significantly up-regulated in tears of diabetic patients. Nicotinic acid and taurine were elevated in the diabetic cohort as well and may represent new biomarkers for diabetes specifically identified in tear fluid. Additionally, systemic medications, like metformin, bisoprolol, and gabapentin, were readily detectable in tears of patients. Conclusions The high number of identified marker molecules found in tear fluid apparently supports disease development prediction, developing preventive approaches as well as tailoring individual patients’ treatments and monitoring treatment efficacy. Tear fluid analysis may also support pharmacokinetic studies and patient compliance control. Supplementary Information The online version contains supplementary material available at 10.1007/s13167-022-00272-7.
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Affiliation(s)
- Julia Brunmair
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria
| | - Andrea Bileck
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria
- Joint Metabolome Facility, University and Medical University Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Gerhard Hagn
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria
| | - Samuel M. Meier-Menches
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria
- Joint Metabolome Facility, University and Medical University Vienna, Vienna, Austria
- Department of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
- VIROS - Vienna Institute for Research in Ocular Surgery - Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Christopher Gerner
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria
- Joint Metabolome Facility, University and Medical University Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
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Kallab M, Hommer N, Schlatter A, Chua J, Tan B, Schmidl D, Hirn C, Findl O, Schmetterer L, Garhöfer G, Wong D. Combining vascular and nerve fiber layer thickness measurements to model glaucomatous focal visual field loss. Ann N Y Acad Sci 2022; 1511:133-141. [PMID: 35029314 PMCID: PMC9305098 DOI: 10.1111/nyas.14732] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 11/01/2021] [Accepted: 11/12/2021] [Indexed: 11/29/2022]
Abstract
We compare the focal structure-function correlation of structural measurements of peripapillary retinal nerve fiber layer thickness (RNFL-T) using optical coherence tomography (OCT), capillary density (CD) measurements using OCT-angiography (OCT-A), or a combination of both, with visual field deviation (VFD) in early to advanced glaucoma. Primary open angle glaucoma patients (n = 46, mean ± SD age: 67 ± 10 years; VF mean deviation: -10.41 ± 6.76 dB) were included in this cross-sectional study. We performed 30-2 standard automated perimetry OCT (3.5-mm diameter ring scan) and 15°×15° OCT-A (superficial vascular complex slab). Based on a nerve fiber trajectory model, each VF test spot was assigned to an OCT-A wedge and an OCT ring-sector. Two univariate linear models (Mv and Mt ) using either CD-based vascular (Mv ) or RNFL-T-based thickness information (Mt ) and one multivariate model using both (Mv:t ) were compared in their associations with measured focal VFD, which were higher for the multivariate model Mv:t (mean ± SD correlation coefficient: 0.710 ± 0.086) than for either nested model (0.627 ± 0.078 for Mv and 0.578 ± 0.095 for Mt ). Using a focal visual field approach, the combination of RNFL-T and CD showed better structure-function correlations than thickness or vascular information only.
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Affiliation(s)
- Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Vienna Institute for Research in Ocular Surgery (VIROS), Hanusch Hospital, Vienna, Austria
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Cornelia Hirn
- Department of Ophthalmology, Hanusch Hospital, Vienna, Austria
| | - Oliver Findl
- Vienna Institute for Research in Ocular Surgery (VIROS), Hanusch Hospital, Vienna, Austria.,Department of Ophthalmology, Hanusch Hospital, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore.,Institute of Molecular and Clinical Ophthalmology Basel, Basel, Switzerland.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Damon Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore.,Institute of Molecular and Clinical Ophthalmology Basel, Basel, Switzerland
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Kallab M, Hommer N, Tan B, Pfister M, Schlatter A, Werkmeister RM, Chua J, Schmidl D, Schmetterer L, Garhöfer G. Plexus‐specific analysis of retinal neurovascular coupling using optical coherence tomography angiography. Acta Ophthalmol 2022. [DOI: 10.1111/j.1755-3768.2022.180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Martin Kallab
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Bingyao Tan
- Singapore Eye Research Institute Singapore
- Institute of Health Technology Nanyang Technological University Singapore
| | - Martin Pfister
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
- Institute of Applied Physics Vienna University of Technology Vienna Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Department of Ophthalmology Hanusch Hospital Vienna Institute for Research in Ocular Surgery‐Karl Landsteiner Institute Vienna Austria
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Jacqueline Chua
- Singapore Eye Research Institute Singapore
- Duke‐NUS Medical School Academic Clinical Program Singapore
| | - Doreen Schmidl
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Singapore Eye Research Institute Singapore
- Institute of Health Technology Nanyang Technological University Singapore
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
- Duke‐NUS Medical School Academic Clinical Program Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
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Kallab M, Hommer N, Schlatter A, Bsteh G, Altmann P, Popa-Cherecheanu A, Pfister M, Werkmeister RM, Schmidl D, Schmetterer L, Garhöfer G. Retinal Oxygen Metabolism and Haemodynamics in Patients With Multiple Sclerosis and History of Optic Neuritis. Front Neurosci 2021; 15:761654. [PMID: 34712117 PMCID: PMC8546107 DOI: 10.3389/fnins.2021.761654] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/22/2021] [Indexed: 12/20/2022] Open
Abstract
Vascular changes and alterations of oxygen metabolism are suggested to be implicated in multiple sclerosis (MS) pathogenesis and progression. Recently developed in vivo retinal fundus imaging technologies provide now an opportunity to non-invasively assess metabolic changes in the neural retina. This study was performed to assess retinal oxygen metabolism, peripapillary capillary density (CD), large vessel density (LVD), retinal nerve fiber layer thickness (RNFLT) and ganglion cell inner plexiform layer thickness (GCIPLT) in patients with diagnosed relapsing multiple sclerosis (RMS) and history of unilateral optic neuritis (ON). 16 RMS patients and 18 healthy controls (HC) were included in this study. Retinal oxygen extraction was modeled using O2 saturations and Doppler optical coherence tomography (DOCT) derived retinal blood flow (RBF) data. CD and LVD were assessed using optical coherence tomography (OCT) angiography. RNFLT and GCIPLT were measured using structural OCT. Measurements were performed in eyes with (MS+ON) and without (MS-ON) history for ON in RMS patients and in one eye in HC. Total oxygen extraction was lowest in MS+ON (1.8 ± 0.2 μl O2/min), higher in MS-ON (2.1 ± 0.5 μl O2/min, p = 0.019 vs. MS+ON) and highest in HC eyes (2.3 ± 0.6 μl O2/min, p = 0.002 vs. MS, ANOVA p = 0.031). RBF was lower in MS+ON (33.2 ± 6.0 μl/min) compared to MS-ON (38.3 ± 4.6 μl/min, p = 0.005 vs. MS+ON) and HC eyes (37.2 ± 4.7 μl/min, p = 0.014 vs. MS+ON, ANOVA p = 0.010). CD, LVD, RNFLT and GCIPL were significantly lower in MS+ON eyes. The present data suggest that structural alterations in the retina of RMS patients are accompanied by changes in oxygen metabolism, which are more pronounced in MS+ON than in MS-ON eyes. Whether these alterations promote MS onset and progression or occur as consequence of disease warrants further investigation. Clinical Trial Registration: ClinicalTrials.gov registry, NCT03401879.
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Affiliation(s)
- Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Vienna Institute for Research in Ocular Surgery (VIROS), Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - Gabriel Bsteh
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Patrick Altmann
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Alina Popa-Cherecheanu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.,Department of Ophthalmology, University Emergency Hospital, Bucharest, Romania
| | - Martin Pfister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Institute of Applied Physics, Vienna University of Technology, Vienna, Austria
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Singapore Eye Research Institute, Singapore, Singapore.,Nanyang Technological University, Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
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Klimek P, Baltic D, Brunner M, Degelsegger-Marquez A, Garhöfer G, Gouya-Lechner G, Herzog A, Jilma B, Kähler S, Mikl V, Mraz B, Ostermann H, Röhl C, Scharinger R, Stamm T, Strassnig M, Wirthumer-Hoche C, Pleiner-Duxneuner J. Quality criteria for Real-World Data in pharmaceutical research and healthcare decision making. An Austrian Expert Consensus. (Preprint). JMIR Med Inform 2021; 10:e34204. [PMID: 35713954 PMCID: PMC9250059 DOI: 10.2196/34204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 05/16/2022] [Accepted: 05/17/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Peter Klimek
- Institute for Science of Complex Systems, Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, Vienna, Austria
- Complexity Science Hub Vienna, Vienna, Austria
| | - Dejan Baltic
- Gesellschaft für Pharmazeutische Medizin, Vienna, Austria
| | | | | | | | | | - Arnold Herzog
- Austrian Medicines and Medical Devices Agency (AGES Medizinmarktaufsicht), Vienna, Austria
| | - Bernd Jilma
- Medical University of Vienna, Vienna, Austria
| | - Stefan Kähler
- Verband der pharmazeutischen Industrie Österreichs (PHARMIG), Vienna, Austria
| | - Veronika Mikl
- Gesellschaft für Pharmazeutische Medizin, Vienna, Austria
| | - Bernhard Mraz
- Gesellschaft für Pharmazeutische Medizin, Vienna, Austria
| | | | | | - Robert Scharinger
- Federal Ministry of Social Affairs, Health, Care and Consumer Protection, Vienna, Austria
| | - Tanja Stamm
- Medical University of Vienna, Vienna, Austria
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Qureshi R, Azuara-Blanco A, Michelessi M, Virgili G, Barbosa Breda J, Cutolo CA, Pazos M, Katsanos A, Garhöfer G, Kolko M, Prokosch-Willing V, Al Rajhi AA, Lum F, Musch D, Gedde S, Li T. What Do We Really Know about the Effectiveness of Glaucoma Interventions?: An Overview of Systematic Reviews. Ophthalmol Glaucoma 2021; 4:454-462. [PMID: 33571689 PMCID: PMC8349936 DOI: 10.1016/j.ogla.2021.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 01/03/2021] [Accepted: 01/26/2021] [Indexed: 01/08/2023]
Abstract
PURPOSE To identify systematic reviews of interventions for glaucoma conditions and to assess their reliability, thereby generating a list of potentially reliable reviews for updating glaucoma practice guidelines. DESIGN Cross-sectional study. PARTICIPANTS Systematic reviews of interventions for glaucoma conditions. METHODS We used a database of systematic reviews and meta-analyses in vision research and eye care maintained by the Cochrane Eyes and Vision United States Satellite. We examined all Cochrane systematic reviews of interventions for glaucoma conditions published before August 7, 2019, and all non-Cochrane systematic reviews of interventions for glaucoma conditions published between January 1, 2014, and August 7, 2019. MAIN OUTCOME MEASURES We assessed eligible reviews for reliability, extracted characteristics, and summarized key findings from reviews classified as reliable. RESULTS Of the 4451 systematic reviews in eyes and vision identified, 129 met our eligibility criteria and were assessed for reliability. Of these, we classified 49 (38%) as reliable. We found open-angle glaucoma (22/49) to be the condition with the most reviews and medical management (17/49) and intraocular pressure (IOP; 43/49) to be the most common interventions and outcomes studied. Most reviews found a high degree of uncertainty in the evidence, which hinders the possibility of making strong recommendations in guidelines. These reviews found high-certainty evidence about a few topics: reducing IOP helps to prevent glaucoma and its progression, prostaglandin analogs are the most effective medical treatment for lowering IOP, laser trabeculoplasty is as effective as medical treatment as a first-line therapy in controlling IOP, the use of IOP-lowering medications in the perioperative or postoperative periods to accompany laser (e.g., trabeculoplasty) reduces the risk of postoperative IOP spikes, conventional surgery (i.e., trabeculectomy) is more effective than medications in reducing IOP, and antimetabolites and β-radiation improve IOP control after trabeculectomy. The evidence is weak regarding the effectiveness of minimally invasive glaucoma surgeries. CONCLUSIONS Most systematic reviews evaluating interventions for glaucoma are of poor reliability. Even among those that may be considered reliable, important limitations exist in the value of information because of the uncertainty of the evidence as well as small and sometimes unimportant clinical differences between interventions.
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Affiliation(s)
- Riaz Qureshi
- Department of Epidemiology, Johns Hopkins University, Baltimore, Maryland
| | - Augusto Azuara-Blanco
- School of Medicine, Dentistry and Biomedical Sciences, Centre for Public Health, Queen's University Belfast, Belfast, United Kingdom
| | | | - Gianni Virgili
- Department of Neurosciences, Psychology Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | - João Barbosa Breda
- Cardiovascular R&D Center, Faculty of Medicine, University of Porto, Porto, Portugal; and Research Group Ophthalmology, Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Carlo Alberto Cutolo
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Sciences, University of Genoa and IRCCS San Martino Policlinic Hospital, Genova, Italy
| | - Marta Pazos
- Department of Ophthalmology, Hospital Clínic of Barcelona, Barcelona, Spain
| | - Andreas Katsanos
- Department of Ophthalmology, University of Ioannina, Ioannina, Greece
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
| | - Miriam Kolko
- Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet-Glostrup, Glostrup, and Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | | | | | - Flora Lum
- American Academy of Ophthalmology, San Francisco, California
| | - David Musch
- Departments of Ophthalmology and Visual Sciences and of Epidemiology, University of Michigan, Ann Arbor, Michigan
| | | | - Tianjing Li
- Department of Ophthalmology, School of Medicine, University of Colorado Denver, Aurora, Colorado.
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Sharifizad M, Schmidl D, Werkmeister RM, Zeisler H, Told R, Binder J, Küssel L, Garhöfer G, Schmetterer L. Retinal vessel diameters, flicker-induced retinal vasodilation and retinal oxygen saturation in high- and low-risk pregnancy. Acta Ophthalmol 2021; 99:628-636. [PMID: 33326186 PMCID: PMC8519143 DOI: 10.1111/aos.14696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 11/10/2020] [Indexed: 01/12/2023]
Abstract
Purpose To compare retinal vascular parameters between high‐risk and low‐risk pregnant women over time during pregnancy. Methods In a longitudinal study, we included pregnant women with normal blood pressure and normal body mass index (BMI, group 1), pregnant women with systemic hypertension and/or overweight (group 2) and age‐matched nonpregnant healthy women (group 3). Using the dynamic vessel analyser (DVA) we investigated flicker‐induced vasodilation in retinal arteries (FLA) and veins (FLV), central retinal arterial and vein equivalent (CRAE, CRVE), arterio‐venous ratio (AVR) and retinal arterial and venous oxygen saturation (SartO2, SveinO2). Study visits were scheduled 2nd trimester (TP 2), 3rd trimester (TP 3) and postpartum (PP). Results Data from 29 women in group 1, 25 women in group 2 and 33 women in group 3 were included for analysis. FLA, FLV, CRAE, CRVE, AVR and SveinO2 were altered in group 2 (p‐values between < 0.001 and 0.009). At TP 3 the differences between groups were most pronounced. In contrast, there were only minor differences between group 1 and 3. Changes in retinal parameters were independently associated with systemic blood pressure and BMI. Conclusions The present analysis indicates that flicker‐induced retinal vasodilation, retinal vessel diameters and retinal oxygen saturation are altered in high‐risk pregnant women. Hence, these parameters are candidate biomarkers for pregnancy complications, a hypothesis that deserves further study.
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Affiliation(s)
- Mozhgan Sharifizad
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Harald Zeisler
- Department of Obstetrics and Gynecology Medical University of Vienna Vienna Austria
| | - Reinhard Told
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Department of Ophthalmology Medical University of Vienna Vienna Austria
| | - Julia Binder
- Department of Obstetrics and Gynecology Medical University of Vienna Vienna Austria
| | - Lorenz Küssel
- Department of Obstetrics and Gynecology Medical University of Vienna Vienna Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
- Singapore Eye Research Institute Singapore Singapore
- School of Chemical and Biomedical Engineering Nanyang Technological University Singapore Singapore
- SERI‐NTU Advanced Ocular Engineering (STANCE) Singapore Singapore
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Schlatter A, Hirn C, Palkovits S, Werkmeister RM, Findl O, Garhöfer G, Schmidl D. Anwendungsmöglichkeiten der optischen Kohärenztomographie beim trockenen Auge. Spektrum Augenheilkd 2021. [DOI: 10.1007/s00717-021-00490-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
ZusammenfassungDurch die stetige Weiterentwicklung und Verbesserung der Technik hat die optische Kohärenztomographie (OCT) in den letzten Jahren neue Möglichkeiten zur Beurteilung der Strukturen des vorderen Augenabschnittes eröffnet. Aufgrund der Darstellung kleinster Strukturen, wie beispielsweise des Tränenfilms, nimmt die OCT in der Diagnostik und Verlaufsbeurteilung des trockenen Auges eine immer wichtigere Rolle ein. Der vorliegende Beitrag gibt einen Überblick über die derzeitigen Einsatzmöglichkeiten der OCT beim trockenen Auge.
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Lorenzo‐Soler L, Olafsdottir OB, Garhöfer G, Jansook P, Kristinsdottir IM, Tan A, Loftsson T, Stefansson E. Angiotensin Receptor Blockers in cyclodextrin nanoparticle eye drops: Ocular pharmacokinetics and pharmacologic effect on intraocular pressure. Acta Ophthalmol 2021; 99:376-382. [PMID: 33191620 DOI: 10.1111/aos.14639] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 09/03/2020] [Accepted: 09/08/2020] [Indexed: 12/16/2022]
Abstract
PURPOSE Orally administered angiotensin II receptor blockers (ARBs) decrease intraocular pressure (IOP). Topical administration may reduce systemic side effects and result in a useful glaucoma drug. The aim of this study is to test the ocular delivery and pharmacologic effect of nanoparticle eye drops containing ARBs (e.g. irbesartan and candesartan). METHODS 1.5% irbesartan and 0.15% candesartan eye drops were applied to rabbits. The pharmacokinetics in cornea and aqueous humour after single eye drop application were studied in 49 rabbits. The effect of the eye drops on IOP was studied in 10 rabbits using an iCare (® TonoVet Plus, iCare, Finland) tonometer and compared with 0.5% timolol eye drops. RESULTS Candesartan lowered IOP from 24.6 ± 5.1 mmHg at baseline to 19.0 ± 2.9 mmHg (mean ± SD, p = 0.030, n = 10) 4 hr after application. Irbesartan lowered IOP from 24.2 ± 1.7 mmHg to 20.2 ± 0.9 mmHg (p = 0.14, n = 10). Timolol decreased the IOP from 24.9 ± 4.2 mmHg to 20.4 ± 4.8 mmHg (mean ± SD, p = 0.036, n = 10). The pharmacokinetics data show that both formulations deliver effective amounts of drug into the intraocular tissues, with irbesartan and candesartan reaching concentrations of 121 ± 69 and 30.43 ± 13.93 ng/g (mean ± SD), respectively, in the aqueous humour 3 hr after a single-dose administration. CONCLUSIONS Topical application of irbesartan and candesartan eye drops delivers effective drug concentrations to the anterior segment of the eye in rabbits, achieving drug concentrations 100 times above the IC50 for angiotensin II receptor and showing an IOP-lowering effect. Angiotensin receptor blocker (ARB) eye drops have potential as a new class of glaucoma drugs.
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Affiliation(s)
| | - Olof Birna Olafsdottir
- Faculty of Medicine University of Iceland Reykjavík Iceland
- Department of Ophthalmology Landspitali University Hospital Reykjavík Iceland
- Oculis ehf. Reykjavík Iceland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Phatsawee Jansook
- Faculty of Pharmaceutical Sciences Chulalongkorn University Bangkok Thailand
| | | | | | | | - Einar Stefansson
- Faculty of Medicine University of Iceland Reykjavík Iceland
- Department of Ophthalmology Landspitali University Hospital Reykjavík Iceland
- Oculis ehf. Reykjavík Iceland
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Kallab M, Schuetzenberger K, Hommer N, Schäfer BJ, Schmidl D, Bergmeister H, Zeitlinger M, Tan A, Jansook P, Loftsson T, Stefansson E, Garhöfer G. Bio-Distribution and Pharmacokinetics of Topically Administered γ-Cyclodextrin Based Eye Drops in Rabbits. Pharmaceuticals (Basel) 2021; 14:ph14050480. [PMID: 34070168 PMCID: PMC8158513 DOI: 10.3390/ph14050480] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/04/2021] [Accepted: 05/14/2021] [Indexed: 12/13/2022] Open
Abstract
The purpose of this study was to evaluate the ocular pharmacokinetics, bio-distribution and local tolerability of γ-cyclodextrin (γCD) based irbesartan 1.5% eye drops and candesartan 0.15% eye drops after single and multiple topical administration in rabbit eyes. In this randomized, controlled study, a total number of 59 New Zealand White albino rabbits were consecutively assigned to two study groups. Group 1 (n = 31) received irbesartan 1.5% and group 2 (n = 28) candesartan 0.15% eye drops. In both groups, single dose and multiple administration pharmacokinetic studies were performed. Rabbits were euthanized at five predefined time points after single-dose administration, whereas multiple-dose animals were dosed for 5 days twice-daily and then euthanized 1 h after the last dose administration. Drug concentration was measured by using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the retinal tissue, vitreous humor, aqueous humor, corneal tissue and in venous blood samples. Pharmacokinetic parameters including maximal drug concentration (Cmax), time of maximal drug concentration (Tmax), half-life and AUC were calculated. To assess local tolerability, six additional rabbits received 1.5% irbesartan eye drops twice daily in one eye for 28 days. Tolerability was assessed using a modified Draize test and corneal sensibility by Cochet Bonnet esthesiometry. Both γCD based eye drops were rapidly absorbed and distributed in the anterior and posterior ocular tissues. Within 0.5 h after single administration, the Cmax of irbesartan and candesartan in retinal tissue was 251 ± 142 ng/g and 63 ± 39 ng/g, respectively. In the vitreous humor, a Cmax of 14 ± 16 ng/g for irbesartan was reached 0.5 h after instillation while Cmax was below 2 ng/g for candesartan. For multiple dosing, the observed Cmean in retinal tissue was 338 ± 124 ng/g for irbesartan and 36 ± 10 ng/g for candesartan, whereas mean vitreous humor concentrations were 13 ± 5 ng/g and <2 ng/g, respectively. The highest plasma concentrations of both irbesartan (Cmax 5.64 ± 4.08 ng/mL) and candesartan (Cmax 4.32 ± 1.04 ng/mL) were reached 0.5 h (Tmax) after single administration. Local tolerability was favorable with no remarkable differences between the treated and the control eyes. These results indicate that irbesartan and candesartan in γCD based nanoparticle eye drops can be delivered to the retinal tissue of the rabbit’s eye in pharmacologically relevant concentrations. Moreover, safety and tolerability profiles appear to be favorable in the rabbit animal model.
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Affiliation(s)
- Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (M.K.); (N.H.); (D.S.); (M.Z.)
| | - Kornelia Schuetzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria; (K.S.); (B.J.S.)
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (M.K.); (N.H.); (D.S.); (M.Z.)
| | - Bhavapriya Jasmin Schäfer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria; (K.S.); (B.J.S.)
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (M.K.); (N.H.); (D.S.); (M.Z.)
| | - Helga Bergmeister
- Center for Biomedical Research, Medical University of Vienna, 1090 Vienna, Austria;
| | - Markus Zeitlinger
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (M.K.); (N.H.); (D.S.); (M.Z.)
| | - Aimin Tan
- Nucro-Technics, Toronto, ON M1H 2W4, Canada;
| | - Phatsawee Jansook
- Pharmaceutics and Industrial Pharmacy, Chulalongkorn University, Bangkok 10330, Thailand;
| | - Thorsteinn Loftsson
- Faculty of Pharmaceutical Science, University of Iceland, 107 Reykjavik, Iceland;
| | - Einar Stefansson
- Department of Ophthalmology, University of Iceland, 101 Reykjavik, Iceland;
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (M.K.); (N.H.); (D.S.); (M.Z.)
- Correspondence: ; Tel.: +43-1-40400-29810
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Hommer N, Schmidl D, Kallab M, Bauer M, Werkmeister RM, Schmetterer L, Abensperg-Traun M, Garhöfer G. The Effect of Orally Administered Low-Dose Dronabinol on Retinal Blood Flow and Oxygen Metabolism in Healthy Subjects. J Ocul Pharmacol Ther 2021; 37:360-366. [PMID: 33999707 DOI: 10.1089/jop.2020.0131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Purpose: The present study was performed to investigate the effect of oral dronabinol, a synthetic tetrahydrocannabinol derivate, on retinal hemodynamics in healthy subjects in a randomized, double-masked, placebo-controlled, 2-way crossover design. Methods: Twenty-four subjects received 5 mg dronabinol on 1 study day and placebo on the other study day. Total retinal blood flow (TRBF) was measured using a custom-built Doppler Optical Coherence Tomography system. Oxygen saturation of major retinal vessels was measured with a commercially available Dynamic Vessel Analyzer. Based on these parameters, retinal oxygen extraction was calculated. Measurements were performed before and after drug administration on both study days. Results: Placebo had no effect on TRBF, retinal arterial or venous oxygen content, and retinal oxygen extraction (P > 0.1 each). In contrast, dronabinol induced a significant increase in TRBF from 38.9 ± 6.1 to 40.7 ± 6.7 μL/min (P < 0.001), which was accompanied by a significant increase in retinal venous oxygen content (from 0.129 ± 0.008 to 0.132 ± 0.009 mL O2/mL, P = 0.02). As no change in retinal arterial oxygen content occurred (P = 0.12), retinal oxygen extraction remained stable (2.2 ± 0.4 μL vs. 2.2 ± 0.4 μL O2/min, P = 0.29). Conclusions: These results indicate that orally administered dronabinol increases TRBF in healthy subjects without altering retinal oxygen extraction. The drug may therefore be a candidate for improving perfusion in patients with ocular vascular disease.
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Affiliation(s)
- Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Martin Bauer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Singapore Eye Research Institute, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
| | - Marihan Abensperg-Traun
- Department of Child and Adolescent Psychiatry, Medical University of Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
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Merkle CW, Augustin M, Harper DJ, Gesperger J, Lichtenegger A, Eugui P, Garhöfer G, Glösmann M, Baumann B. High-resolution, depth-resolved vascular leakage measurements using contrast-enhanced, correlation-gated optical coherence tomography in mice. Biomed Opt Express 2021; 12:1774-1791. [PMID: 33996197 PMCID: PMC8086440 DOI: 10.1364/boe.415227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/22/2021] [Accepted: 01/24/2021] [Indexed: 06/09/2023]
Abstract
Vascular leakage plays a key role in vision-threatening retinal diseases such as diabetic retinopathy and age-related macular degeneration. Fluorescence angiography is the current gold standard for identification of leaky vasculature in vivo, however it lacks depth resolution, providing only 2D images that complicate precise identification and localization of pathological vessels. Optical coherence tomography (OCT) has been widely adopted for clinical ophthalmology due to its high, micron-scale resolution and rapid volumetric scanning capabilities. Nevertheless, OCT cannot currently identify leaky blood vessels. To address this need, we have developed a new method called exogenous contrast-enhanced leakage OCT (ExCEL-OCT) which identifies the diffusion of tracer particles around leaky vasculature following injection of a contrast agent. We apply this method to a mouse model of retinal neovascularization and demonstrate high-resolution 3D vascular leakage measurements in vivo for the first time.
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Affiliation(s)
- Conrad W. Merkle
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Marco Augustin
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Danielle J. Harper
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Johanna Gesperger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Antonia Lichtenegger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Pablo Eugui
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Martin Glösmann
- Core Facility for Research and Technology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Bernhard Baumann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
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Schmidl D, Szalai L, Kiss OG, Schmetterer L, Garhöfer G. A Phase II, Multicenter, Randomized, Placebo-Controlled, Double-Masked Trial of a Topical Estradiol Ophthalmic Formulation in Postmenopausal Women with Moderate-to-Severe Dry Eye Disease. Adv Ther 2021; 38:1975-1986. [PMID: 33710587 DOI: 10.1007/s12325-021-01680-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/19/2021] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Dry eye disease (DED) is a multifactorial disorder of the ocular surface. The current phase II study was performed to assess the safety and dose regimen of a recently developed topical estradiol formulation for the treatment of DED. METHODS A total of 104 postmenopausal women suffering from moderate-to-severe DED were included. Topical 17-β-estradiol-3-phosphate eye drops were administered in three different dosage groups (group 1, 0.05% twice daily; group 2, 0.1% morning, vehicle in the evening; group 3, 0.1% twice daily) and vehicle twice daily as control group for a total period of 3 months. Clinical signs including Schirmer's test and corneal staining were assessed at baseline and at days 14, 30, 60, and 90. Symptoms of DED were measured using the symptom assessment in dry eye (SANDE) test at the same time points. Safety was assessed via frequency of adverse events. RESULTS Schirmer's test II wetting distance significantly increased in all four groups from baseline to day 90 without significant difference between groups (group 1, + 5.6 ± 6.7 mm/5 min; group 2, + 3.7 ± 4.2 mm/5 min; group 3, + 4.8 ± 4.5 mm/5 min; group 4, + 4.0 ± 5.3 mm/5 min). Statistical significance versus baseline was reached earlier in the treatment groups versus the control group. Corneal staining was significantly reduced after the 3-month treatment period with no significant difference between treatment groups. Staining of the inferior cornea, however, showed a significantly more pronounced decrease in the highest dose group compared to vehicle (p = 0.0463). Symptoms score as assessed with the SANDE test decreased at the end of the treatment period in all four groups. Estradiol eye drops showed a favorable safety profile. CONCLUSION Our results show that both estradiol eye drops and vehicle are safe and reduce signs and symptoms in postmenopausal women with moderate-to-severe DED. Although the study failed to reach the primary outcome to demonstrate a significant difference between the estradiol eye drops and vehicle in Schirmer's test, improvement occurred earlier in the active groups compared to the control group. The data of the current study will serve as a basis for a larger phase III study to establish a potential therapeutic effect of topical estradiol eye drops. CLINICAL TRIAL REGISTRATION Clinicaltrials.gov registry NCT03821415.
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Kallab M, Hommer N, Tan B, Pfister M, Schlatter A, Werkmeister RM, Chua J, Schmidl D, Schmetterer L, Garhöfer G. Plexus-specific effect of flicker-light stimulation on the retinal microvasculature assessed with optical coherence tomography angiography. Am J Physiol Heart Circ Physiol 2020; 320:H23-H28. [PMID: 33275537 DOI: 10.1152/ajpheart.00495.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In neural tissues, the coupling between neural activity and blood flow is a physiological key principle in blood flow regulation. We used optical coherence tomography angiography to investigate stimulus-evoked hemodynamic responses in different microvascular layers of the human retina. Twenty-two healthy subjects were included. Vessel density before and during light stimulation was measured using optical coherence tomography angiography and assessed for the superficial, intermediate, and deep capillary plexus of the retinal circulation. Volumetric blood flow was measured using a custom-built Doppler optical coherence tomography system. Our results show that flicker stimulation induced a significant increase in the vessel density of +9.9 ± 6.7% in the superficial capillary plexus, +6.6 ± 1.7% in the intermediate capillary plexus, and +4.9 ± 2.3% in the deep capillary plexus. The hyperemic response of the superficial capillary plexus was significantly higher compared to the intermediate capillary plexus (P = 0.02) and deep capillary plexus (P = 0.002). Volumetric retinal blood flow increased by +39.9 ± 34.9% in arteries and by +29.8 ± 16.8% in veins. In conclusion, we showed a strong increase in the retinal microvascular density in response to light stimulation, with the most pronounced effect in the superficial capillary plexus. This is compatible with the hypothesis that the microvasculature exerts an important function in mediating functional hyperemia in humans.NEW & NOTEWORTHY We present vessel density alterations in response to flicker stimulation using optical coherence tomography angiography and identified the superficial capillary plexus as the layer with the most pronounced effect. This points out the physiological importance of the microvasculature in mediating functional hyperemia and suggests a fine-tuned plexus-specific mechanism to meet cellular metabolic demands.
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Affiliation(s)
- Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore.,Institute of Health Technology, Nanyang Technological University, Singapore
| | - Martin Pfister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Medical University of Vienna, Vienna, Austria.,Institute of Applied Physics, Vienna University of Technology, Vienna, Austria
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Department of Ophthalmology, Vienna Institute for Research in Ocular Surgery-Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Singapore Eye Research Institute, Singapore.,Institute of Health Technology, Nanyang Technological University, Singapore.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore.,Institute of Clinical and Experimental Ophthalmology, Basel, Switzerland
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
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Chua J, Hu Q, Ke M, Tan B, Hong J, Yao X, Hilal S, Venketasubramanian N, Garhöfer G, Cheung CY, Wong TY, Chen CLH, Schmetterer L. Retinal microvasculature dysfunction is associated with Alzheimer's disease and mild cognitive impairment. Alzheimers Res Ther 2020; 12:161. [PMID: 33276820 PMCID: PMC7718666 DOI: 10.1186/s13195-020-00724-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 11/10/2020] [Indexed: 12/20/2022]
Abstract
Background The retina and brain share many neuronal and vasculature characteristics. We investigated the retinal microvasculature in Alzheimer’s disease (AD) and mild cognitive impairment (MCI) using optical coherence tomography angiography (OCTA). Methods In this cross-sectional study, 24 AD participants, 37 MCI participants, and 29 controls were diagnosed according to internationally accepted criteria. OCTA images of the superficial and deep capillary plexus (SCP, DCP) of the retinal microvasculature were obtained using a commercial OCTA system (Zeiss Cirrus HD-5000 with AngioPlex, Carl Zeiss Meditec, Dublin, CA). The main outcome measures were vessel density (VD) and fractal dimension (FD) in the SCP and DCP within a 2.5-mm ring around the fovea which were compared between groups. Perfusion density of large vessels and foveal avascular zone (FAZ) area were additional outcome parameters. Results Age, gender, and race did not differ among groups. However, there was a significant difference in diabetes status (P = 0.039) and systolic blood pressure (P = 0.008) among the groups. After adjusting for confounders, AD participants showed significantly decreased VD in SCP and DCP (P = 0.006 and P = 0.015, respectively) and decreased FD in SCP (P = 0.006), compared to controls. MCI participants showed significantly decreased VD and FD only in SCP (P = 0.006 and P < 0.001, respectively) and not the DCP (P > 0.05) compared with controls. There was no difference in the OCTA variables between AD and MCI (P > 0.05). Perfusion density of large vessels and FAZ area did not differ significantly between groups (P > 0.05). Conclusions and relevance Eyes of patients with AD have significantly reduced macular VD in both plexuses whereas MCI participants only showed reduction in the superficial plexus. Changes in the retinal microvasculature and capillary network may offer a valuable insight on the brain in AD. Supplementary information The online version contains supplementary material available at 10.1186/s13195-020-00724-0.
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Affiliation(s)
- Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Sha Tin, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Sha Tin, Singapore
| | - Qinglan Hu
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Sha Tin, Singapore
| | - Mengyuan Ke
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Sha Tin, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Sha Tin, Singapore.,Institute for Health Technologies, Nanyang Technological University, Sha Tin, Singapore
| | - Jimmy Hong
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore
| | - Xinwen Yao
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Sha Tin, Singapore.,Institute for Health Technologies, Nanyang Technological University, Sha Tin, Singapore
| | - Saima Hilal
- Memory Aging and Cognition Centre, Departments of Pharmacology and Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Sha Tin, Singapore.,Saw Swee Hock School of Public Health, National University of Singapore, Sha Tin, Singapore.,Department of Pharmacology, National University of Singapore, Singapore, Singapore
| | - Narayanaswamy Venketasubramanian
- Memory Aging and Cognition Centre, Departments of Pharmacology and Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Sha Tin, Singapore.,Raffles Neuroscience Centre, Raffles Hospital, Singapore, Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria
| | - Carol Y Cheung
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Sha Tin, Hong Kong
| | - Tien Yin Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Sha Tin, Singapore
| | - Christopher Li-Hsian Chen
- Memory Aging and Cognition Centre, Departments of Pharmacology and Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Sha Tin, Singapore
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, 20 College Road, The Academia, Level 6, Discovery Tower, Singapore, 169856, Singapore. .,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, National University of Singapore, Sha Tin, Singapore. .,SERI-NTU Advanced Ocular Engineering (STANCE), Sha Tin, Singapore. .,Institute for Health Technologies, Nanyang Technological University, Sha Tin, Singapore. .,Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria. .,Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria. .,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland.
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Szegedi S, Dal‐Bianco P, Stögmann E, Traub‐Weidinger T, Rainer M, Masching A, Schmidl D, Werkmeister RM, Chua J, Schmetterer L, Garhöfer G. Anatomical and functional changes in the retina in patients with Alzheimer's disease and mild cognitive impairment. Acta Ophthalmol 2020; 98:e914-e921. [PMID: 32212415 PMCID: PMC7687124 DOI: 10.1111/aos.14419] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 03/04/2020] [Indexed: 01/14/2023]
Abstract
PURPOSE There is evidence that mild cognitive impairment (MCI) or Alzheimer's disease (AD) is accompanied by alterations in the retina. The current study was performed to investigate structural and functional changes in patients with systemic neurodegenerative disease. METHODS A total of 47 patients with either MCI or AD and 43 healthy age- and sex-matched control subjects were included. Inclusion criteria for MCI were abnormal memory function and a mini-mental state examination (MMSE) score >26 points, for patients with AD a diagnosis of probable AD of mild to moderate degree and an MMSE score in the range of 20-26. Retinal blood flow was measured using a Doppler optical coherence tomography (OCT) system. Retinal vessel diameter, oxygen saturation and flicker-induced vasodilatation were measured using a Vessel Analyzer. Retinal nerve fibre layer thickness (RNFLT) was assessed using an OCT system. RESULTS Global RNFLT was lower in patients compared to healthy controls (93.7 ± 12.8 µm versus 99.1 ± 9.0 µm, p = 0.02). The same was found in regards to retinal arterial blood flow, which was 9.3 ± 2.4 and 12.3 ± 3.2 μl/min in the patient and control groups, respectively (p < 0.001). Mean retinal arterial diameter was reduced in patients (76.0 ± 8.9 µm versus 80.6 ± 8.0 µm, p = 0.03). Arteriovenous difference in oxygen saturation was lower in patients (20.4 ± 5.1% versus 23.5 ± 4.0%, p < 0.01). No difference in the flicker response was observed. CONCLUSION In patients with MCI and AD, arteriovenous difference in oxygen saturation, retinal blood flow and arterial vessel diameter was reduced. No difference was found in flicker response between groups. This indicates alterations in retinal oxygen metabolism in patients with neurodegenerative disease.
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Affiliation(s)
- Stephan Szegedi
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
| | - Peter Dal‐Bianco
- Department of NeurologyMedical University of ViennaViennaAustria
| | | | - Tatjana Traub‐Weidinger
- Division of Nuclear MedicineDepartment of Biomedical Imaging and Image‐guided TherapyMedical University of ViennaViennaAustria
| | - Michael Rainer
- Department of PsychiatrySocial and Medical Centre East – Danube HospitalViennaAustria
- Karl Landsteiner Institute for Memory and Alzheimer ResearchViennaAustria
| | - Andreas Masching
- Department of PsychiatrySocial and Medical Centre East – Danube HospitalViennaAustria
| | - Doreen Schmidl
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Jacqueline Chua
- Singapore Eye Research InstituteSingapore National Eye CentreSingapore CitySingapore
- Ophthalmology and Visual Sciences Academic Clinical ProgramDuke‐NUS Medical SchoolSingapore CitySingapore
| | - Leopold Schmetterer
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
- Singapore Eye Research InstituteSingapore National Eye CentreSingapore CitySingapore
- Ophthalmology and Visual Sciences Academic Clinical ProgramDuke‐NUS Medical SchoolSingapore CitySingapore
- Lee Kong Chian School of MedicineNanyang Technological UniversitySingapore CitySingapore
- Institute of Molecular and Clinical OphthalmologyBaselSwitzerland
| | - Gerhard Garhöfer
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
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Tan B, Sim R, Chua J, Wong DWK, Yao X, Garhöfer G, Schmidl D, Werkmeister RM, Schmetterer L. Approaches to quantify optical coherence tomography angiography metrics. Ann Transl Med 2020; 8:1205. [PMID: 33241054 PMCID: PMC7576021 DOI: 10.21037/atm-20-3246] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Optical coherence tomography (OCT) has revolutionized the field of ophthalmology in the last three decades. As an OCT extension, OCT angiography (OCTA) utilizes a fast OCT system to detect motion contrast in ocular tissue and provides a three-dimensional representation of the ocular vasculature in a non-invasive, dye-free manner. The first OCT machine equipped with OCTA function was approved by U.S. Food and Drug Administration in 2016 and now it is widely applied in clinics. To date, numerous methods have been developed to aid OCTA interpretation and quantification. In this review, we focused on the workflow of OCTA-based interpretation, beginning from the generation of the OCTA images using signal decorrelation, which we divided into intensity-based, phase-based and phasor-based methods. We further discussed methods used to address image artifacts that are commonly observed in clinical settings, to the algorithms for image enhancement, binarization, and OCTA metrics extraction. We believe a better grasp of these technical aspects of OCTA will enhance the understanding of the technology and its potential application in disease diagnosis and management. Moreover, future studies will also explore the use of ocular OCTA as a window to link ocular vasculature to the function of other organs such as the kidney and brain.
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Affiliation(s)
- Bingyao Tan
- Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore
| | - Ralene Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Damon W K Wong
- Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore
| | - Xinwen Yao
- Institute for Health Technologies, Nanyang Technological University, Singapore, Singapore.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE) Program, Nanyang Technological University, Singapore, Singapore.,Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore.,Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore.,Department of Ophthalmology, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
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Schmidl D, Schlatter A, Chua J, Tan B, Garhöfer G, Schmetterer L. Novel Approaches for Imaging-Based Diagnosis of Ocular Surface Disease. Diagnostics (Basel) 2020; 10:diagnostics10080589. [PMID: 32823769 PMCID: PMC7460546 DOI: 10.3390/diagnostics10080589] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/28/2020] [Accepted: 08/10/2020] [Indexed: 02/07/2023] Open
Abstract
Imaging has become indispensable in the diagnosis and management of diseases in the posterior part of the eye. In recent years, imaging techniques for the anterior segment are also gaining importance and are nowadays routinely used in clinical practice. Ocular surface disease is often synonymous with dry eye disease, but also refers to other conditions of the ocular surface, such as Meibomian gland dysfunction or keratitis and conjunctivitis with different underlying causes, i.e., allergies or infections. Therefore, correct differential diagnosis and treatment of ocular surface diseases is crucial, for which imaging can be a helpful tool. A variety of imaging techniques have been introduced to study the ocular surface, such as anterior segment optical coherence tomography, in vivo confocal microscopy, or non-contact meibography. The present review provides an overview on how these techniques can be used in the diagnosis and management of ocular surface disease and compares them to clinical standard methods such as slit lamp examination or staining of the cornea or conjunctiva. Although being more cost-intensive in the short term, in the long term, the use of ocular imaging can lead to more individualized diagnoses and treatment decisions, which in turn are beneficial for affected patients as well as for the healthcare system. In addition, imaging is more objective and provides good documentation, leading to an improvement in patient follow-up and education.
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Affiliation(s)
- Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (A.S.); (G.G.)
| | - Andreas Schlatter
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (A.S.); (G.G.)
- Department of Ophthalmology, Vienna Institute for Research in Ocular Surgery-Karl Landsteiner Institute, Hanusch Hospital, 1140 Vienna, Austria
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (B.T.)
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Nanyang Technological University, Singapore 639798, Singapore
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (B.T.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Nanyang Technological University, Singapore 639798, Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (A.S.); (G.G.)
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (A.S.); (G.G.)
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (B.T.)
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Nanyang Technological University, Singapore 639798, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
- Institute of Molecular and Clinical Ophthalmology, CH-4031 Basel, Switzerland
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria
- Correspondence: ; Tel.: +43-1-40400-29810; Fax: +43-1-40400-29990
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Hommer N, Kallab M, Szegedi S, Puchner S, Stjepanek K, Bauer M, Werkmeister RM, Schmetterer L, Abensperg‐Traun M, Garhöfer G, Schmidl D. The Effect of Orally Administered Dronabinol on Optic Nerve Head Blood Flow in Healthy Subjects-A Randomized Clinical Trial. Clin Pharmacol Ther 2020; 108:155-161. [PMID: 31977076 PMCID: PMC7325313 DOI: 10.1002/cpt.1797] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 01/04/2020] [Indexed: 02/04/2023]
Abstract
It has been hypothesized that besides its intraocular pressure (IOP) lowering potential, tetrahydrocannabinol (THC) may also improve ocular hemodynamics. The aim of the present study was to investigate whether single oral administration of dronabinol, a synthetic THC, alters optic nerve head blood flow (ONHBF) and its regulation in healthy subjects. The study was carried out in a randomized, placebo-controlled, double-masked, two-way crossover design in 24 healthy subjects. For each study participant, 2 study days were scheduled, on which they either received capsules containing 5 mg dronabinol or placebo. ONHBF was measured with laser Doppler flowmetry at rest and while the study participants performed isometric exercise for 6 minutes to increase mean arterial blood pressure (MAP). This was repeated 1 hour after drug intake. Ocular perfusion pressure (OPP) was calculated as 2/3MAP-IOP. Dronabinol was well tolerated and no cannabinoid-related psychoactive effects were reported. Neither administration of dronabinol nor placebo had an effect on IOP, MAP, or OPP. In contrast, dronabinol significantly increased ONHBF at rest by 9.5 ± 8.1%, whereas placebo did not show a change in ONHBF (0.3 ± 7.4% vs. baseline, P < 0.001 between study days). Dronabinol did not alter the autoregulatory response of ONHBF to isometric exercise. In conclusion, the present data indicate that low-dose dronabinol increases ONHBF in healthy subjects without affecting IOP, OPP, or inducing psychoactive side effects. In addition, dronabinol does not alter the autoregulatory response of ONHBF to an experimental increase in OPP. Further studies are needed to investigate whether this effect can also be observed in patients with glaucoma.
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Affiliation(s)
- Nikolaus Hommer
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
| | - Martin Kallab
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
| | - Stephan Szegedi
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
| | - Stefan Puchner
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Kristina Stjepanek
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
| | - Martin Bauer
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Leopold Schmetterer
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
- Singapore Eye Research InstituteSingaporeSingapore
- Lee Kong Chian School of MedicineNanyang Technological UniversitySingaporeSingapore
- Ophthalmology and Visual Sciences Academic Clinical ProgramDuke‐NUS Medical SchoolSingaporeSingapore
- SERI‐NTU Advanced Ocular Engineering (STANCE)SingaporeSingapore
- Institute of OphthalmologyBaselSwitzerland
| | | | - Gerhard Garhöfer
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
| | - Doreen Schmidl
- Department of Clinical PharmacologyMedical University of ViennaViennaAustria
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Szegedi S, Hommer N, Kallab M, Puchner S, Schmidl D, Werkmeister RM, Garhöfer G, Schmetterer L. Repeatability and Reproducibility of Total Retinal Blood Flow Measurements Using Bi-Directional Doppler OCT. Transl Vis Sci Technol 2020; 9:34. [PMID: 32832239 PMCID: PMC7414639 DOI: 10.1167/tvst.9.7.34] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 04/28/2020] [Indexed: 12/01/2022] Open
Abstract
Purpose To investigate the repeatability and reproducibility of total retinal blood flow measurements using a custom-built dual-beam bidirectional Doppler optical coherence tomography (OCT) system in healthy subjects. Methods Repeatability and reproducibility were analyzed in 10 and 34 healthy subjects, respectively. For repeatability, measurements were taken twice within 30 minutes, for reproducibility, twice within two to five weeks. Two analysis approaches were compared for calculation of absolute blood velocities: a previously published approach resulting in values for total arterial (QA,abs) and total venous blood flow (QV,abs) and a novel approach taking into account that there is a fixed relation between the phase shift in the two OCT channels (QA,new, QV,new). Repeatability and reproducibility were quantified using intraclass correlation coefficients (ICCs). Results For QA,abs and QV,abs, ICC values between 0.78 and 0.84 were obtained. QA,new and QV,new values revealed better repeatability and reproducibility as compared to the convential appoach. Repeatability ICCs for QA,new and QV,new were between 0.91 and 0.93, and reproducibility ICCs were between 0.87 and 0.91 indicating excellent reproducibility. Good agreement was observed between total retinal blood flow values as measured from retinal arteries and retinal veins. Conclusions Measurement of total retinal blood flow using dual-beam Doppler OCT shows excellent reproducibility, which can further be improved by using a novel algorithm for calculating blood velocities in retinal vessels. Translational Relevance Our data indicate that dual-beam Doppler OCT can be used for longitudinal studies. Hence, quantitative retinal blood flow may be established as a biomarker for progression vascular eye diseases.
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Affiliation(s)
- Stephan Szegedi
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Martin Kallab
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Stefan Puchner
- Department of Clinical Pharmacology, Medical University of Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.,School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore.,SERI-NTU Advanced Ocular Engineering (STANCE), Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore.,Institute of Clinical and Experimental Ophthalmology, Basel, Switzerland
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Chua J, Sim R, Tan B, Wong D, Yao X, Liu X, Ting DSW, Schmidl D, Ang M, Garhöfer G, Schmetterer L. Optical Coherence Tomography Angiography in Diabetes and Diabetic Retinopathy. J Clin Med 2020; 9:E1723. [PMID: 32503234 PMCID: PMC7357089 DOI: 10.3390/jcm9061723] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 05/24/2020] [Accepted: 06/02/2020] [Indexed: 12/21/2022] Open
Abstract
Diabetic retinopathy (DR) is a common complication of diabetes mellitus that disrupts the retinal microvasculature and is a leading cause of vision loss globally. Recently, optical coherence tomography angiography (OCTA) has been developed to image the retinal microvasculature, by generating 3-dimensional images based on the motion contrast of circulating blood cells. OCTA offers numerous benefits over traditional fluorescein angiography in visualizing the retinal vasculature in that it is non-invasive and safer; while its depth-resolved ability makes it possible to visualize the finer capillaries of the retinal capillary plexuses and choriocapillaris. High-quality OCTA images have also enabled the visualization of features associated with DR, including microaneurysms and neovascularization and the quantification of alterations in retinal capillary and choriocapillaris, thereby suggesting a promising role for OCTA as an objective technology for accurate DR classification. Of interest is the potential of OCTA to examine the effect of DR on individual retinal layers, and to detect DR even before it is clinically detectable on fundus examination. We will focus the review on the clinical applicability of OCTA derived quantitative metrics that appear to be clinically relevant to the diagnosis, classification, and management of patients with diabetes or DR. Future studies with longitudinal design of multiethnic multicenter populations, as well as the inclusion of pertinent systemic information that may affect vascular changes, will improve our understanding on the benefit of OCTA biomarkers in the detection and progression of DR.
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Affiliation(s)
- Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
| | - Ralene Sim
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
| | - Bingyao Tan
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- Institute of Health Technologies, Nanyang Technological University, Singapore 639798, Singapore
| | - Damon Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- Institute of Health Technologies, Nanyang Technological University, Singapore 639798, Singapore
| | - Xinwen Yao
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- Institute of Health Technologies, Nanyang Technological University, Singapore 639798, Singapore
| | - Xinyu Liu
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
| | - Daniel S. W. Ting
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (G.G.)
| | - Marcus Ang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (G.G.)
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 169856, Singapore; (J.C.); (R.S.); (B.T.); (D.W.); (X.Y.); (X.L.); (D.S.W.T.); (M.A.)
- Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore 639798, Singapore
- Institute of Health Technologies, Nanyang Technological University, Singapore 639798, Singapore
- Department of Clinical Pharmacology, Medical University of Vienna, 1090 Vienna, Austria; (D.S.); (G.G.)
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, 1090 Vienna, Austria
- Institute of Molecular and Clinical Ophthalmology, CH-4031 Basel, Switzerland
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Calzetti G, Mora P, Favilla S, Ottonelli G, Devincenzi G, Carta A, Tedesco S, Mursch-Edlmayr A, Garhöfer G, Gandolfi S, Schmetterer L. Assessment of Choroidal Neovascularization Perfusion: A Pilot Study With Laser Speckle Flowgraphy. Transl Vis Sci Technol 2020; 9:9. [PMID: 32821481 PMCID: PMC7401962 DOI: 10.1167/tvst.9.5.9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 03/03/2020] [Indexed: 12/01/2022] Open
Abstract
Purpose The purpose of this study was to quantify perfusion in the area of choroidal neovascularization (CNV) using laser speckle flowgraphy (LSFG) before and after intravitreal anti-vascular endothelial growth factor (VEGF) injection. Methods Retrospective case series. Fifteen eyes of 15 patients with treatment-naïve CNV due to age-related macular degeneration (AMD) and with available LSFG images were included. The main outcome was the mean blur rate (MBR) quantified as a measure of perfusion within the CNV area observed on indocyanine green angiography. Twelve patients had available longitudinal data until one month after the injection, used to evaluate changes in perfusion, central macular thickness (CMT), visual acuity, and ocular perfusion pressure. Reproducibility of LSFG measurements was investigated at each time point from two images taken within five minutes. Results Intraclass correlation coefficients for LSFG measurements were higher than 0.8 indicating excellent reproducibility. There was a significant decrease in perfusion after one week (-26.4 ± 14.4%; P = 0.027), whereas, after one month, perfusion was no longer significantly different from baseline (P = 0.121). CMT showed a progressive decrease over the follow-up period. Changes in perfusion were strongly correlated with changes in CMT after one week, but not thereafter. Conclusions This pilot study suggests a method to select a region in the CNV area to quantify perfusion using LSFG. MBR could represent a parameter possibly related to regrowth of the CNV after anti-VEGF treatment. Large-scale studies are needed to assess the usefulness of LSFG in defining re-treatment criteria for neovascular AMD. Translational Relevance LSFG technology to quantify perfusion could provide useful biomarkers for therapeutic management of CNV.
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Affiliation(s)
| | - Paolo Mora
- Ophthalmology Unit, University Hospital of Parma, Parma, Italy
| | | | | | | | - Arturo Carta
- Ophthalmology Unit, University Hospital of Parma, Parma, Italy
| | | | - Anna Mursch-Edlmayr
- Department of Ophthalmology, Kepler University Clinic, Johannes Kepler University, Linz, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.,Singapore Eye Research Institute, Singapore.,Nanyang Technological University, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Institute of Ophthalmology, Basel, Switzerland
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47
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Schmidl D, Bata AM, Szegedi S, Aranha Dos Santos V, Stegmann H, Fondi K, Krösser S, Werkmeister RM, Schmetterer L, Garhöfer G. Influence of Perfluorohexyloctane Eye Drops on Tear Film Thickness in Patients with Mild to Moderate Dry Eye Disease: A Randomized Controlled Clinical Trial. J Ocul Pharmacol Ther 2020; 36:154-161. [DOI: 10.1089/jop.2019.0092] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Doreen Schmidl
- Department of Clinical Pharmacology and Medical University of Vienna, Vienna, Austria
| | - Ahmed M. Bata
- Department of Clinical Pharmacology and Medical University of Vienna, Vienna, Austria
| | - Stephan Szegedi
- Department of Clinical Pharmacology and Medical University of Vienna, Vienna, Austria
| | | | - Hannes Stegmann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Klemens Fondi
- Department of Clinical Pharmacology and Medical University of Vienna, Vienna, Austria
| | - Sonja Krösser
- Department of Clinical Development, Novaliq GmbH, Heidelberg, Germany
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology and Medical University of Vienna, Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Singapore Eye Research Institute, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology and Medical University of Vienna, Vienna, Austria
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48
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Schuetzenberger K, Pfister M, Messner A, Garhöfer G, Hohenadl C, Pfeiffenberger U, Schmetterer L, Werkmeister RM. Cutaneous optical coherence tomography for longitudinal volumetric assessment of intradermal volumes in a mouse model. Sci Rep 2020; 10:4245. [PMID: 32144359 PMCID: PMC7060266 DOI: 10.1038/s41598-020-61276-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 02/24/2020] [Indexed: 11/10/2022] Open
Abstract
Clinical evaluation of skin lesions requires precise and reproducible technologies for their qualitative and quantitative assessment. In this study, we investigate the applicability of a custom-built dermatologic OCT system for longitudinal assessment of intradermal volumes in a mouse model. The OCT, based on an akinetic swept laser working at 1310 nm was employed for visualization and quantification of intradermal deposits of three different hyaluronic acid-based hydrogel formulations - one commercial and two test substances. Hydrogels were applied in 22 BALB/c mice, and measurements were performed over a six-month time period. All hydrogels increased in volume within the first weeks and degraded steadily thereafter. The half-lifes of the test hydrogels (27.2 ± 13.6 weeks for Hydrogel 1, 31.5 ± 17.2 weeks for Hydrogel 2) were higher in comparison to the commercially available HA hydrogel (21.4 ± 12.0 weeks), although differences were not significant. The sphericity parameter was used for evaluation of the deposit geometry. While on the injection day the sphericities were similar (~0.75 ± 0.04), at later time points significant differences between the different test substances were found (T24: PRV 0.59 ± 0.09, Hydrogel 1 0.70 ± 0.11, Hydrogel 2 0.78 ± 0.07; p ≤ 0.012 for all pairs). This study shows the applicability of OCT imaging for quantitative assessment of the volumetric behavior of intradermal deposits in vivo.
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Affiliation(s)
- Kornelia Schuetzenberger
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria
| | - Martin Pfister
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria
- Institute of Applied Physics, Vienna University of Technology, Wiedner Hauptstr. 8-10, 1040, Vienna, Austria
| | - Alina Messner
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Gerhard Garhöfer
- Medical University of Vienna, Department of Clinical Pharmacology, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Christine Hohenadl
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria
- Croma Pharma GmbH, Cromazeile 2, 2100, Leobendorf, Austria
| | - Ulrike Pfeiffenberger
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria
| | - Leopold Schmetterer
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria
- Medical University of Vienna, Department of Clinical Pharmacology, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Singapore Eye Research Institute, 20 College Road Discovery Tower Level 6, The Academia, Singapore, 169856, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Dr, Singapore, 636921, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore, Singapore
- SERI-NTU Advanced Ocular Engineering (STANCE), Singapore, Singapore
- Institute of Ophthalmology, 4031, Basel, Switzerland
| | - René M Werkmeister
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Währinger Gürtel 18-20, 1090, Vienna, Austria.
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Vienna, Austria.
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49
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Stegmann H, Werkmeister RM, Pfister M, Garhöfer G, Schmetterer L, dos Santos VA. Deep learning segmentation for optical coherence tomography measurements of the lower tear meniscus. Biomed Opt Express 2020; 11:1539-1554. [PMID: 32206427 PMCID: PMC7075621 DOI: 10.1364/boe.386228] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/27/2020] [Accepted: 01/28/2020] [Indexed: 05/22/2023]
Abstract
The tear meniscus contains most of the tear fluid and therefore is a good indicator for the state of the tear film. Previously, we used a custom-built optical coherence tomography (OCT) system to study the lower tear meniscus by automatically segmenting the image data with a thresholding-based segmentation algorithm (TBSA). In this report, we investigate whether the results of this image segmentation algorithm are suitable to train a neural network in order to obtain similar or better segmentation results with shorter processing times. Considering the class imbalance problem, we compare two approaches, one directly segmenting the tear meniscus (DSA), the other first localizing the region of interest and then segmenting within the higher resolution image section (LSA). A total of 6658 images labeled by the TBSA were used to train deep convolutional neural networks with supervised learning. Five-fold cross-validation reveals a sensitivity of 96.36% and 96.43%, a specificity of 99.98% and 99.86% and a Jaccard index of 93.24% and 93.16% for the DSA and LSA, respectively. Average segmentation times are up to 228 times faster than the TBSA. Additionally, we report the behavior of the DSA and LSA in cases challenging for the TBSA and further test the applicability to measurements acquired with a commercially available OCT system. The application of deep learning for the segmentation of the tear meniscus provides a powerful tool for the assessment of the tear film, supporting studies for the investigation of the pathophysiology of dry eye-related diseases.
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Affiliation(s)
- Hannes Stegmann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Medical University of Vienna, Austria
| | - René M. Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Medical University of Vienna, Austria
| | - Martin Pfister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Medical University of Vienna, Austria
- Institute of Applied Physics, Vienna University of Technology, Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Leopold Schmetterer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Medical University of Vienna, Austria
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - Valentin Aranha dos Santos
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
- Christian Doppler Laboratory for Ocular and Dermal Effects of Thiomers, Medical University of Vienna, Austria
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Kallab M, Schützenberger K, Hommer N, Jasmin Schäfer B, Tan A, Jansook P, Stefansson E, Garhöfer G. Pharmacokinetics of angiotensin‐receptor blocker in cyclodextrin nanoparticle eye drops in rabbits. Acta Ophthalmol 2019. [DOI: 10.1111/j.1755-3768.2019.5328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Martin Kallab
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | - Kornelia Schützenberger
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Nikolaus Hommer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
| | | | | | - Phatsawee Jansook
- Pharmaceutics and Industrial Pharmacy Chulalongkorn University Bangkok Thailand
| | | | - Gerhard Garhöfer
- Department of Clinical Pharmacology Medical University of Vienna Vienna Austria
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