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Tillmann A, Turgut F, Munk MR. Optical coherence tomography angiography in neovascular age-related macular degeneration: comprehensive review of advancements and future perspective. Eye (Lond) 2024:10.1038/s41433-024-03295-8. [PMID: 39147864 DOI: 10.1038/s41433-024-03295-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 06/09/2024] [Accepted: 08/05/2024] [Indexed: 08/17/2024] Open
Abstract
Optical coherence tomography angiography (OCTA) holds promise in enhancing the care of various retinal vascular diseases, including neovascular age-related macular degeneration (nAMD). Given nAMD's vascular nature and the distinct vasculature of macular neovascularization (MNV), detailed analysis is expected to gain significance. Research in artificial intelligence (AI) indicates that en-face OCTA views may offer superior predictive capabilities than spectral domain optical coherence tomography (SD-OCT) images, highlighting the necessity to identify key vascular parameters. Analyzing vasculature could facilitate distinguishing MNV subtypes and refining diagnosis. Future studies correlating OCTA parameters with clinical data might prompt a revised classification system. However, the combined utilization of qualitative and quantitative OCTA biomarkers to enhance the accuracy of diagnosing disease activity remains underdeveloped. Discrepancies persist regarding the optimal biomarker for indicating an active lesion, warranting comprehensive prospective studies for validation. AI holds potential in extracting valuable insights from the vast datasets within OCTA, enabling researchers and clinicians to fully exploit its OCTA imaging capabilities. Nevertheless, challenges pertaining to data quantity and quality pose significant obstacles to AI advancement in this field. As OCTA gains traction in clinical practice and data volume increases, AI-driven analysis is expected to further augment diagnostic capabilities.
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Affiliation(s)
- Anne Tillmann
- Augenarzt Praxisgemeinschaft Gutblick, Pfäffikon, Switzerland
| | - Ferhat Turgut
- Augenarzt Praxisgemeinschaft Gutblick, Pfäffikon, Switzerland
- Department of Ophthalmology, Stadtspital Zürich, Zürich, Switzerland
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
| | - Marion R Munk
- Augenarzt Praxisgemeinschaft Gutblick, Pfäffikon, Switzerland.
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, 3010, Bern, Switzerland.
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60208, USA.
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Braun M, Saini C, Sun JA, Shen LQ. The Role of Optical Coherence Tomography Angiography in Glaucoma. Semin Ophthalmol 2024; 39:412-423. [PMID: 38643350 DOI: 10.1080/08820538.2024.2343049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 04/08/2024] [Accepted: 04/09/2024] [Indexed: 04/22/2024]
Abstract
Glaucoma is the leading cause of irreversible vision loss and comprises a group of chronic optic neuropathies characterized by progressive retinal ganglion cell (RGC) loss. Various etiologies, including impaired blood supply to the optic nerve, have been implicated for glaucoma pathogenesis. Optical coherence tomography angiography (OCTA) is a non-invasive imaging modality for visualizing the ophthalmic microvasculature. Using blood flow as an intrinsic contrast agent, it distinguishes blood vessels from the surrounding tissue. Vessel density (VD) is mainly used as a metric for quantifying the ophthalmic microvasculature. The key anatomic regions for OCTA in glaucoma are the optic nerve head area including the peripapillary region, and the macular region. Specifically, VD of the superficial peripapillary and superficial macular microvasculature is reduced in glaucoma patients compared to unaffected subjects, and VD correlates with functional deficits measured by visual field (VF). This renders OCTA similar in diagnostic capabilities compared to structural retinal nerve fiber layer (RNFL) thickness measurements, especially in early glaucoma. Furthermore, in cases where RNFL thickness measurements are limited due to artifact or floor effect, OCTA technology can be used to evaluate and monitor glaucoma, such as in eyes with high myopia and eyes with advanced glaucoma. However, the clinical utility of OCTA in glaucoma management is limited due to the prevalence of imaging artifacts. Overall, OCTA can play a complementary role in structural OCT imaging and VF testing to aid in the diagnosis and monitoring of glaucoma.
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Affiliation(s)
- Maximilian Braun
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
- Department of Ophthalmology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Chhavi Saini
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Jessica A Sun
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Lucy Q Shen
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
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3
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Yargi-Ozkocak B, Altan C, Kemer-Atik B, Basarir B. Evaluation of Optical Coherence Tomography Angiography Findings in Pars Planitis and Multiple Sclerosis Associated Intermediate Uveitis in Remission. Curr Eye Res 2024; 49:717-724. [PMID: 38433455 DOI: 10.1080/02713683.2024.2323520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 02/20/2024] [Indexed: 03/05/2024]
Abstract
PURPOSE To evaluate the microvasculature during remission in patients with pars planitis (PP-IU) and multiple sclerosis-associated intermediate uveitis (MS-IU) using optical coherence tomography angiography (OCT-A). METHODS Single-center, descriptive, case-control study was conducted. Adult patients (≥16 years) with IU in remission (PP-IU and MS-IU) and healthy age-sex matched healthy controls (HC) were enrolled to the study. Demographic/clinical features, best-corrected visual acuity (BCVA), ocular findings, neurological symptoms and preferred treatments were recorded. The presence of cystoid macular edema (CME) during follow-up was recorded. All IU patients in remission and HC subjects were scanned with OCT-A. Foveal avascular zone (FAZ) areas of superficial and deep capillary plexus (SCP/DCP) and vascular densities of SCP, DCP and choriocapillaris were obtained from OCT-A and compared between the groups. RESULTS Sixty-nine eyes of 37 IU patients in remission and 20 HC were included (44 eyes/23 patients in PP-IU, 25/14 in MS-IU, 40/20 in HC). No statistically significant differences were observed in terms of demographic or clinical characteristics of the patients. The vascular density in the SCP was significantly reduced in the PP-IU and MS-IU groups compared to the HC group (p < .05). Nevertheless, there were no significant changes in any of the OCTA parameters between the IU groups. Uveitis duration was found to be correlated with enlargement of the FAZ area in PP-IU (p = .039). CONCLUSION OCTA may not be useful in differentiating between PP-IU and MS-IU. Nevertheless, the primary implication in SCP potentially elucidates the pathogenesis of these two subtypes of IU, which are characterized by a shared pathogenesis. The monitoring of the FAZ area in the PP-IU group is valuable in terms of chronicity.
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Affiliation(s)
- Berru Yargi-Ozkocak
- Beyoglu Eye Training and Research Hospital, University of Health Sciences Turkey, Istanbul, Turkey
| | - Cigdem Altan
- Beyoglu Eye Training and Research Hospital, University of Health Sciences Turkey, Istanbul, Turkey
| | - Burcu Kemer-Atik
- Beyoglu Eye Training and Research Hospital, University of Health Sciences Turkey, Istanbul, Turkey
| | - Berna Basarir
- Beyoglu Eye Training and Research Hospital, University of Health Sciences Turkey, Istanbul, Turkey
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4
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Bae SH, Bae K, Yoon CK, Park UC, Park KH, Lee EK. MORPHOLOGICAL BIOMARKERS PREDICTING EXUDATIVE CONVERSION IN TYPE 1 NONEXUDATIVE MACULAR NEOVASCULARIZATION USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY. Retina 2024; 44:1006-1014. [PMID: 38346091 DOI: 10.1097/iae.0000000000004066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2024]
Abstract
PURPOSE To investigate the incidence and morphological biomarkers to predict the exudative conversion in eyes with type 1 nonexudative macular neovascularization using swept-source optical coherence tomography angiography. METHODS Macular neovascularizations were detected using the retinal pigment epithelium-to-retinal pigment epithelium-fit slab of swept-source optical coherence tomography angiography scan. Depending on whether exudation developed within a year, the eyes were divided into two groups: active and silent. Qualitative and quantitative optical coherence tomography angiography parameters of the two groups were evaluated to discriminate the biomarkers associated with exudative conversion. RESULTS Of the 40 eyes, nine developed exudation within 1 year (incidence rate 22.5%). The active group exhibited a significantly higher "anastomosis and loops" pattern, greater "vessel density," increased "junction density," fewer "number of end points," and lower "lacunarity" compared with the silent group. "Anastomosis and loops" and higher "vessel density" were correlated with the active group in multivariate analyses. A predictive model combining these biomarkers achieved 95% accuracy in predicting exudative conversion. CONCLUSION At 12 months, the risk of exudation was 22.5%, and "anastomosis and loops" and "vessel density" were useful optical coherence tomography angiography biomarkers for predicting exudative conversion in eyes with type 1 nonexudative macular neovascularization. For eyes with a high risk of exudative conversion, more frequent follow-up is recommended.
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Affiliation(s)
- Su Ho Bae
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea
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5
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Fang DQ, Yang DW, Mai XT, Cheung CY, Chen HY. Repeatability, interocular correlation and agreement of optic nerve head vessel density in healthy eyes: a swept-source optical coherence tomographic angiography study. Int J Ophthalmol 2024; 17:896-903. [PMID: 38766332 PMCID: PMC11074198 DOI: 10.18240/ijo.2024.05.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 12/12/2023] [Indexed: 05/22/2024] Open
Abstract
AIM To assess the repeatability, interocular correlation, and agreement of quantitative swept-source optical coherence tomography angiography (OCTA) optic nerve head (ONH) parameters in healthy subjects. METHODS Thirty-three healthy subjects were enrolled. The ONH of both eyes were imaged four times by a swept-source-OCTA using a 3 mm ×3 mm scanning protocol. Images of the radial peripapillary capillary were analyzed by a customized Matlab program, and the vessel density, fractal dimension, and vessel diameter index were measured. The repeatability of the four scans was determined by the intraclass correlation coefficient (ICC). The most well-centered optic disc from the four repeated scans was then selected for the interocular correlation and agreement analysis using the Pearson correlation coefficient, ICC and Bland-Altman plots. RESULTS All swept-source-OCTA ONH parameters exhibited certain repeatability, with ICC>0.760 and coefficient of variation (CoV)≤7.301%. The obvious interocular correlation was observed for papillary vessel density (ICC=0.857), vessel diameter index (ICC=0.857) and fractal dimension (ICC=0.906), while circumpapillary vessel density exhibited moderate interocular correlation (ICC=0.687). Bland-Altman plots revealed an agreement range of -5.26% to 6.21% for circumpapillary vessel density. CONCLUSION OCTA ONH parameters demonstrate good repeatability in healthy subjects. The interocular correlations of papillary vessel density, fractal dimension and vessel diameter index are high, but the correlation for circumpapillary vessel density is moderate.
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Affiliation(s)
- Dan-Qi Fang
- Joint Shantou International Eye Center, Shantou University & the Chinese University of Hong Kong, Shantou 515041, Guangdong Province, China
| | - Da-Wei Yang
- Department of Ophthalmology and Visual Sciences, Chinese University of Hong Kong, Hong Kong 999077, China
| | - Xiao-Ting Mai
- Joint Shantou International Eye Center, Shantou University & the Chinese University of Hong Kong, Shantou 515041, Guangdong Province, China
| | - Carol Y Cheung
- Department of Ophthalmology and Visual Sciences, Chinese University of Hong Kong, Hong Kong 999077, China
| | - Hao-Yu Chen
- Joint Shantou International Eye Center, Shantou University & the Chinese University of Hong Kong, Shantou 515041, Guangdong Province, China
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Fekrazad S, Hassanzadeh G, Salehi MA, Mozafar M, Shahrabi Farahani M, Arevalo JF. Optical coherence tomography angiography measurements in systemic lupus erythematosus: A systematic review and meta-analysis. Surv Ophthalmol 2024:S0039-6257(24)00047-X. [PMID: 38744406 DOI: 10.1016/j.survophthal.2024.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 04/25/2024] [Accepted: 04/29/2024] [Indexed: 05/16/2024]
Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disease affecting various organs. Ocular involvement, particularly retinopathy, is common, emphasizing the significance of early detection. Optical coherence tomography angiography (OCTA), a non-invasive imaging technique, reveals microvascular changes, aiding SLE diagnosis and monitoring. This study evaluates OCTA's effectiveness in detecting SLE-related retinal alterations. A systemic search was undertaken across PubMed, Embase, and Scopus databases to identify studies presenting OCTA measurements in SLE patients compared to healthy controls. The meta-analysis, employing either fixed-effects or random-effects models based on heterogeneity levels, was conducted. Additionally, subgroup and sensitivity analyses, meta-regression, and quality assessments were carried out. Thirteen studies of 565 eyes in the SLE group and 560 eyes in the control group were included. The meta-analyses revealed that SLE patients had a significantly lower retinal vessel density in the superficial and deep capillary plexus layers, choriocapillaris flow area, and foveal avascular zone (FAZ) circularity index compared to healthy controls, but that there were no significant differences in the FAZ area and perimeter. These findings highlight how OCTA can provide a noninvasive assessment of SLE effects on the retinal microvasculature, potentially presenting a reliable biomarker for more precise detection of SLE and disease activity monitoring.
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Affiliation(s)
- Sepehr Fekrazad
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; International Network for Photomedicine and Photodynamic Therapy (INPMPDT), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | | | | | - Mehrdad Mozafar
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | | | - J Fernando Arevalo
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Kostolna K, Reiter GS, Frank S, Coulibaly LM, Fuchs P, Röggla V, Gumpinger M, Leitner Barrios GP, Mares V, Bogunovic H, Schmidt-Erfurth U. A Systematic Prospective Comparison of Fluid Volume Evaluation across OCT Devices Used in Clinical Practice. OPHTHALMOLOGY SCIENCE 2024; 4:100456. [PMID: 38317867 PMCID: PMC10840339 DOI: 10.1016/j.xops.2023.100456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 12/05/2023] [Accepted: 12/11/2023] [Indexed: 02/07/2024]
Abstract
Objective Treatment decisions in neovascular age-related macular degeneration (nAMD) are mainly based on subjective evaluation of OCT. The purpose of this cross-sectional study was to provide a comparison of qualitative and quantitative differences between OCT devices in a systematic manner. Design Prospective, cross-sectional study. Subjects One hundred sixty OCT volumes, 40 eyes of 40 patients with nAMD. Methods Patients from clinical practice were imaged with 4 different OCT devices during one visit: (1) Spectralis Heidelberg; (2) Cirrus; (3) Topcon Maestro2; and (4) Topcon Triton. Intraretinal fluid (IRF), subretinal fluid (SRF), and pigment epithelial detachment (PED) were manually annotated in all cubes by trained human experts to establish fluid measurements based on expert-reader annotations. Intraretinal fluid, SRF, and PED volume were quantified in nanoliters (nL). Bland-Altman plots were created to analyze the agreement of measurements in the central 1 and 6 mm. The Friedman test was performed to test for significant differences in the central 1, 3, and 6 mm. Main Outcome Measures Intraretinal fluid, SRF, and PED volume. Results In the central 6 mm, there was a trend toward higher IRF and PED volumes in Spectralis images compared with the other devices and no differences in SRF volume. In the central 1 mm, the standard deviation of the differences ranged from ± 3 nL to ± 6 nL for IRF, from ± 3 nL to ± 4 nL for SRF, and from ± 7 nL to ± 10 nL for PED in all pairwise comparisons. Manually annotated IRF and SRF volumes showed no significant differences in the central 1 mm. Conclusions Fluid volume quantification achieved excellent reliability in all 3 retinal compartments on images obtained from 4 OCT devices, particularly for clinically relevant IRF and SRF values. Although fluid volume quantification is reliable in all 4 OCT devices, switching OCT devices might lead to deviating fluid volume measurements with higher agreement in the central 1 mm compared with the central 6 mm, with highest agreement for SRF volume in the central 1 mm. Understanding device-dependent differences is essential for expanding the interpretation and implementation of pixel-wise fluid volume measurements in clinical practice and in clinical trials. Financial Disclosures Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Klaudia Kostolna
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | - Gregor S. Reiter
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | - Sophie Frank
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | | | - Philipp Fuchs
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | - Veronika Röggla
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | - Markus Gumpinger
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
| | | | - Virginia Mares
- Department of Ophthalmology, Medical University of Vienna, Vienna, Austria
- Department of Ophthalmology, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Hrvoje Bogunovic
- Christian Doppler Laboratory for Artificial Intelligence in Retina, Department of Ophthalmology, Medical University Vienna, Vienna, Austria
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8
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Untracht GR, Durkee MS, Zhao M, Kwok-Cheung Lam A, Sikorski BL, Sarunic MV, Andersen PE, Sampson DD, Chen FK, Sampson DM. Towards standardising retinal OCT angiography image analysis with open-source toolbox OCTAVA. Sci Rep 2024; 14:5979. [PMID: 38472220 PMCID: PMC10933365 DOI: 10.1038/s41598-024-53501-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 02/01/2024] [Indexed: 03/14/2024] Open
Abstract
Quantitative assessment of retinal microvasculature in optical coherence tomography angiography (OCTA) images is important for studying, diagnosing, monitoring, and guiding the treatment of ocular and systemic diseases. However, the OCTA user community lacks universal and transparent image analysis tools that can be applied to images from a range of OCTA instruments and provide reliable and consistent microvascular metrics from diverse datasets. We present a retinal extension to the OCTA Vascular Analyser (OCTAVA) that addresses the challenges of providing robust, easy-to-use, and transparent analysis of retinal OCTA images. OCTAVA is a user-friendly, open-source toolbox that can analyse retinal OCTA images from various instruments. The toolbox delivers seven microvascular metrics for the whole image or subregions and six metrics characterising the foveal avascular zone. We validate OCTAVA using images collected by four commercial OCTA instruments demonstrating robust performance across datasets from different instruments acquired at different sites from different study cohorts. We show that OCTAVA delivers values for retinal microvascular metrics comparable to the literature and reduces their variation between studies compared to their commercial equivalents. By making OCTAVA publicly available, we aim to expand standardised research and thereby improve the reproducibility of quantitative analysis of retinal microvascular imaging. Such improvements will help to better identify more reliable and sensitive biomarkers of ocular and systemic diseases.
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Affiliation(s)
- Gavrielle R Untracht
- Department of Health Technology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
- School of Biosciences, The University of Surrey, Guildford, GU27XH, UK
| | | | - Mei Zhao
- Centre for Myopia Research, School of Optometry, Faculty of Health and Social Science, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Andrew Kwok-Cheung Lam
- Centre for Myopia Research, School of Optometry, Faculty of Health and Social Science, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Bartosz L Sikorski
- Department of Ophthalmology, Nicolaus Copernicus University, 85-090, Bydgoszcz, Poland
- International Center for Translational Eye Research (ICTER), Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Marinko V Sarunic
- Department of Medical Physics and Biomedical Engineering, University College London, London, WC1E6BT, UK
- Institute of Ophthalmology, University College London, London, EC1V2PD, UK
| | - Peter E Andersen
- Department of Health Technology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - David D Sampson
- School of Computer Science and Electronic Engineering, The University of Surrey, Guildford, GU27XH, UK
| | - Fred K Chen
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), The University of Western Australia, Perth, WA, 6009, Australia
- Department of Ophthalmology, Royal Perth Hospital, Perth, WA, 6000, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC, 3002, Australia
| | - Danuta M Sampson
- School of Biosciences, The University of Surrey, Guildford, GU27XH, UK.
- Institute of Ophthalmology, University College London, London, EC1V2PD, UK.
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), The University of Western Australia, Perth, WA, 6009, Australia.
- Department of Optometry, School of Allied Health, The University of Western Australia, Perth, WA, 6009, Australia.
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Yalcinkaya Cakir G, Solmaz B, Cakir I, Pasaoglu IB, Taskapili M. Optical coherence tomography angiography findings in optic disc drusen and idiopathic intracranial hypertension. Eur J Ophthalmol 2024; 34:566-573. [PMID: 37424290 DOI: 10.1177/11206721231187664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
PURPOSE To evaluate the changes in peripapillary microvascularity in idiopathic intracranial hypertension (IIH) and optic disc drusen (ODD) patients, by comparing them with those in healthy individuals, via optical coherence tomography angiography (OCTA). METHODS Sixty-two eyes of 33 patients with ODD, 58 eyes of 30 patients with IIH, and 70 eyes of 70 healthy people were imaged for 6 × 6-mm optic disc scans on a spectral-domain OCTA. Vascular densities in superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC) of ODD, IIH, and healthy eyes were compared with a one-way analysis of variance. Post-hoc analysis was performed with the Gabriel test. RESULTS There was a significant decrease in peripapillary vessel density in SCP, DCP, and CC in patients with IIH compared to the control group (p < 0.05). In ODD patients, especially peripapillary vessel density in DCP was significantly reduced compared to the control group (p < 0.05). Peripapillary vessel density in DCP was significantly lower in the IIH group than ODD group (p < 0.05). CONCLUSIONS Peripapillary vascular density may be affected during the course of the disease in both IIH and ODD. Compared to healthy individuals, the decrease in vascular density in these patients and the consequent decrease in perfusion in the peripapillary region may guide the pathogenesis of the complications in the course of these two diseases. Although vascular density in DCP and CC differs significantly between IIH and ODD, case-controlled studies are needed to evaluate the role of OCTA in the differential diagnosis of IHH and ODD.
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Affiliation(s)
| | - Banu Solmaz
- Faculty of Medicine, Ophthalmology Department, Medipol University, Istanbul, Turkey
| | - Ihsan Cakir
- Beyoglu Eye Training and Research Hospital, University of Health Sciences Turkey, Istanbul, Turkey
| | - Isil Basgil Pasaoglu
- Beyoglu Eye Training and Research Hospital, University of Health Sciences Turkey, Istanbul, Turkey
| | - Muhittin Taskapili
- Beyoglu Eye Training and Research Hospital, University of Health Sciences Turkey, Istanbul, Turkey
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10
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Tian M, Zeng G, Zinkernagel M, Tappeiner C, Wolf S, Munk MR. Assessment of choriocapillaris and choroidal vascular changes in posterior uveitis using swept-source wide-field optical coherence tomography angiography. Br J Ophthalmol 2024; 108:386-390. [PMID: 36627172 DOI: 10.1136/bjo-2022-322209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 01/01/2023] [Indexed: 01/12/2023]
Abstract
PURPOSE To evaluate choriocapillaris (CC) and choroidal vascular changes in patients with posterior uveitis using swept-source (SS) wide-field optical coherence tomography angiography (OCTA). METHOD Consecutive patients with posterior uveitis were evaluated using 3×3 mm and 12×12 mm OCTA scan patterns and montage images of 5×12×12 mm or 2×15×9 mm, covering approximately 70°-90° of the retina. The images were quantitatively and qualitatively analysed and compared with healthy controls. RESULTS Eighty-six eyes of 56 patients with posterior uveitis (mean age 45.2±19.9 years; 58.9% female), and 38 eyes of 19 age-matched healthy controls (57.9% female) were included. The mean perfusion density (PD) in 3×3 mm and 12×12 mm CC scans was significantly lower in eyes with posterior uveitis compared with those of healthy controls. However, no significant difference in the mean PD of choroidal scans was found comparing eyes with posterior uveitis and healthy controls. The mean PD in eyes with active disease was significantly higher compared with the inactive eyes on 12×12 mm choroidal scans (55.61% vs 51.25%, p=0.02), while no difference was found in the CC slabs. CONCLUSION CC and choroidal assessment using OCTA provides useful information in patients with posterior uveitis. SS-OCTA metrics of the CC and choroidal slabs are promising tools in uveitis patients in the future. TRIAL REGISTRATION NUMBER NCT02811536.
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Affiliation(s)
- Meng Tian
- Department of Ophthalmology, Inselspital, University of Bern, Bern, Switzerland
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, Beijing, China
| | - Guodong Zeng
- SITEM Center for Translational Medicine and Biomedical Entrepreneurship, University of Bern, Bern, Switzerland
| | - Martin Zinkernagel
- Department of Ophthalmology, Inselspital, University of Bern, Bern, Switzerland
| | - Christoph Tappeiner
- Department of Ophthalmology, Inselspital, University of Bern, Bern, Switzerland
- Department of Ophthalmology, Pallas Klinik, Olten, Switzerland
- Department of Ophthalmology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
- Department of Ophthalmology, San Raffaele Scientific Institute, University Vita-Salute, Milan, Italy
| | - Sebastian Wolf
- Department of Ophthalmology, Inselspital, University of Bern, Bern, Switzerland
| | - Marion R Munk
- Department of Ophthalmology, Inselspital, University of Bern, Bern, Switzerland
- Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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11
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König M, Seeböck P, Gerendas BS, Mylonas G, Winklhofer R, Dimakopoulou I, Schmidt-Erfurth UM. Quality assessment of colour fundus and fluorescein angiography images using deep learning. Br J Ophthalmol 2023; 108:98-104. [PMID: 36418144 PMCID: PMC10804038 DOI: 10.1136/bjo-2022-321963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 11/11/2022] [Indexed: 11/24/2022]
Abstract
BACKGROUND/AIMS Image quality assessment (IQA) is crucial for both reading centres in clinical studies and routine practice, as only adequate quality allows clinicians to correctly identify diseases and treat patients accordingly. Here we aim to develop a neural network for automated real-time IQA in colour fundus (CF) and fluorescein angiography (FA) images. METHODS Training and evaluation of two neural networks were conducted using 2272 CF and 2492 FA images, with binary labels in four (contrast, focus, illumination, shadow and reflection) and three (contrast, focus, noise) modality specific categories plus an overall quality ranking. Performance was compared with a second human grader, evaluated on an external public dataset and in a clinical trial use-case. RESULTS The networks achieved a F1-score/area under the receiving operator characteristic/precision recall curve of 0.907/0.963/0.966 for CF and 0.822/0.918/0.889 for FA in overall quality prediction with similar results in most categories. A clear relation between model uncertainty and prediction error was observed. In the clinical trial use-case evaluation, the networks achieved an accuracy of 0.930 for CF and 0.895 for FA. CONCLUSION The presented method allows automated IQA in real time, demonstrating human-level performance for CF as well as FA. Such models can help to overcome the problem of human intergrader and intragrader variability by providing objective and reproducible IQA results. It has particular relevance for real-time feedback in multicentre clinical studies, when images are uploaded to central reading centre portals. Moreover, automated IQA as preprocessing step can support integrating automated approaches into clinical practice.
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Affiliation(s)
- Michael König
- Department of Ophthalmology and Optometry, Medical University of Vienna, Wien, Austria
| | - Philipp Seeböck
- Department of Ophthalmology and Optometry, Medical University of Vienna, Wien, Austria
| | - Bianca S Gerendas
- Department of Ophthalmology and Optometry, Medical University of Vienna, Wien, Austria
| | - Georgios Mylonas
- Department of Ophthalmology and Optometry, Medical University of Vienna, Wien, Austria
| | - Rudolf Winklhofer
- Department of Ophthalmology and Optometry, Medical University of Vienna, Wien, Austria
| | - Ioanna Dimakopoulou
- Department of Ophthalmology and Optometry, Medical University of Vienna, Wien, Austria
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Bisen JB, Heisel CJ, Duffy BV, Decker NL, Fukuyama H, Boughanem GO, Fawzi AA, Lavine JA. Association between macrophage-like cell density and ischemia metrics in diabetic eyes. Exp Eye Res 2023; 237:109703. [PMID: 38652673 PMCID: PMC11040107 DOI: 10.1016/j.exer.2023.109703] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/18/2023] [Accepted: 10/27/2023] [Indexed: 04/25/2024]
Abstract
We previously showed that macrophage-like cells (MLCs) are increased in eyes with advanced diabetic retinopathy (DR). Here, we hypothesized that MLC density was correlated with ischemia using optical coherence tomography angiography (OCTA) and ultra-widefield fluorescein angiography (UWF-FA). Treatment-naïve diabetic eyes were prospectively imaged with repeated OCTA (average 5.3 scans per eye) and UWF-FA imaging. OCTA images were registered and averaged to generate a superficial capillary plexus (SCP), deep capillary plexus (DCP), and MLC slab. We calculated geometric perfusion deficit (GPD), vessel length density, and vessel density for the SCP and DCP. MLC density was quantified by two masked graders and averaged. Ischemia on UWF-FA was measured to generate a non-perfusion area (NPA) and index (NPI). Since MLC density was non-parametrically distributed, MLC density was correlated with ischemia metrics using Spearman correlations. Forty-five treatment-naïve eyes of 45 patients (59 ± 12 years of age; 56% female) were imaged. We included 6 eyes with no DR, 7 eyes with mild non-proliferative DR (NPDR), 22 moderate NPDR, 4 severe NPDR, and 6 PDR eyes. MLC density between graders was highly correlated (r = 0.9592, p < 0.0001). MLC density was correlated with DCP GPD (r = 0.296, p = 0.049), but no other OCTA ischemia metrics. MLC density was also correlated with UWF-FA NPA (r = 0.330, p = 0.035) and NPI (r = 0.332, p = 0.034). MLC density was correlated with total ischemia on UWF-FA and local DCP GPD. Since both UWF-FA and DCP non-perfusion are associated with higher risk for DR progression, MLC density could be another potential biomarker for DR progression.
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Affiliation(s)
- Jay B Bisen
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Curtis J Heisel
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Brandon V Duffy
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Nicole L Decker
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Hisashi Fukuyama
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Ghazi O Boughanem
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Amani A Fawzi
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Jeremy A Lavine
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA.
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13
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Waheed NK, Rosen RB, Jia Y, Munk MR, Huang D, Fawzi A, Chong V, Nguyen QD, Sepah Y, Pearce E. Optical coherence tomography angiography in diabetic retinopathy. Prog Retin Eye Res 2023; 97:101206. [PMID: 37499857 PMCID: PMC11268430 DOI: 10.1016/j.preteyeres.2023.101206] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 07/29/2023]
Abstract
There remain many unanswered questions on how to assess and treat the pathology and complications that arise from diabetic retinopathy (DR). Optical coherence tomography angiography (OCTA) is a novel and non-invasive three-dimensional imaging method that can visualize capillaries in all retinal layers. Numerous studies have confirmed that OCTA can identify early evidence of microvascular changes and provide quantitative assessment of the extent of diseases such as DR and its complications. A number of informative OCTA metrics could be used to assess DR in clinical trials, including measurements of the foveal avascular zone (FAZ; area, acircularity, 3D para-FAZ vessel density), vessel density, extrafoveal avascular zones, and neovascularization. Assessing patients with DR using a full-retinal slab OCTA image can limit segmentation errors and confounding factors such as those related to center-involved diabetic macular edema. Given emerging data suggesting the importance of the peripheral retinal vasculature in assessing and predicting DR progression, wide-field OCTA imaging should also be used. Finally, the use of automated methods and algorithms for OCTA image analysis, such as those that can distinguish between areas of true and false signals, reconstruct images, and produce quantitative metrics, such as FAZ area, will greatly improve the efficiency and standardization of results between studies. Most importantly, clinical trial protocols should account for the relatively high frequency of poor-quality data related to sub-optimal imaging conditions in DR and should incorporate time for assessing OCTA image quality and re-imaging patients where necessary.
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Affiliation(s)
- Nadia K Waheed
- New England Eye Center, Tufts University School of Medicine, Boston, MA, USA.
| | - Richard B Rosen
- New York Eye and Ear Infirmary of Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yali Jia
- School of Medicine, Casey Eye Institute, Oregon Health and Science University, Portland, OR, USA
| | - Marion R Munk
- Augenarzt-Praxisgemeinschaft Gutblick AG, Pfäffikon, Switzerland
| | - David Huang
- School of Medicine, Casey Eye Institute, Oregon Health and Science University, Portland, OR, USA
| | - Amani Fawzi
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Victor Chong
- Institute of Ophthalmology, University College London, London, UK
| | - Quan Dong Nguyen
- Byers Eye Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Yasir Sepah
- Byers Eye Institute, Stanford University School of Medicine, Stanford, CA, USA
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14
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Angeli O, Hajdu D, Jeney A, Czifra B, Nagy BV, Balazs T, Nemoda DJ, Somfai GM, Nagy ZZ, Peto T, Schneider M. Qualitative and quantitative comparison of two semi-manual retinal vascular density analyzing methods on optical coherence tomography angiography images of healthy individuals. Sci Rep 2023; 13:16981. [PMID: 37813968 PMCID: PMC10562399 DOI: 10.1038/s41598-023-44234-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 10/05/2023] [Indexed: 10/11/2023] Open
Abstract
The aim of this study was to evaluate qualitative and quantitative differences in vascular density analysis of an established and a novel alternative for post-processing on optical coherence tomography angiography (OCTA) images in healthy individuals. OCTA examinations of 38 subjects were performed. After extracting the images, two semi-manual post-processing techniques, the already established Mexican hat filtering (MHF) and an alternative, the Shanbhag thresholding (ST) were applied. We assessed Vessel Density (VD), Skeleton Density (SkD) and Vessel Diameter Index (VDI). We analyzed the results in order to establish similarities or potentially relevant differences. Regarding SkD and VD, MHF generally gave higher values than ST. Simultaneously, mean values were also predominantly higher by MHF; however, standard deviations (SD) were higher by ST (range [mean ± SD]: 0.054 ± 0.038 to 0.134 ± 0.01 and 0.134 ± 0.095 to 0.362 ± 0.028 vs 0.012 ± 0.014 to 0.087 ± 0.03 and 0.039 ± 0.047 to 0.4 ± 0.095 for SkD and VD with MHF vs SkD and VD with ST, respectively). Values of VDI were considerably higher with ST than with MHF, while standard deviation was still significantly higher with ST (range [mean ± SD]: 2.459 ± 0.144 to 2.71 ± 0.084 and 2.983 ± 0.929 to 5.19 ± 1.064 for VDI with MHF and ST, respectively). The noise level reduction of the two methods were almost identical (noise levels: 65.8% with MHT and 65.24% with ST). Using MHF, the vascular network gets more fragmented by an average of 40% compared to ST. Both methods allow the segmentation of the vascular network and the examination of vascular density parameters, but they produce largely inconsistent results. To determine if these inconsistent results are clinically meaningful, and which method is more suitable for clinical use, our results provide further evidence that detailed understanding of the image analysis method is essential for reliable decision making for patients with retinal pathology. For longitudinal monitoring, use of the same image processing method is recommended.
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Affiliation(s)
- Orsolya Angeli
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
| | - Dorottya Hajdu
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
- Department of Ophthalmology and Optometry, Vienna Clinical Trial Center (VTC), Medical University of Vienna, Vienna, Austria
| | - Aniko Jeney
- Department of Ophthalmology, Flor Ferenc Hospital, Kistarcsa, Hungary
| | - Balint Czifra
- Department of Mechatronics, Optics and Mechanical Engineering, Budapest University of Technology and Economics, Budapest, Hungary
| | - Balazs Vince Nagy
- Department of Mechatronics, Optics and Mechanical Engineering, Budapest University of Technology and Economics, Budapest, Hungary
| | | | | | - Gabor Mark Somfai
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
- Department of Ophthalmology, Stadtspital Zurich, Zurich, Switzerland
- Spross Research Institute, Zurich, Switzerland
| | - Zoltan Z Nagy
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary
| | - Tunde Peto
- Centre for Public Health, Queen's University Belfast, Belfast, UK
- Research Unit of Ophthalmology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Miklos Schneider
- Department of Ophthalmology, Semmelweis University, Budapest, Hungary.
- Department of Ophthalmology, Rigshospitalet Glostrup, Valdemar Hansens Vej 1-23, 2600, Glostrup, Denmark.
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15
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Salehi MA, Rezagholi F, Mohammadi S, Zakavi SS, Jahanshahi A, Gouravani M, Yazdanpanah G, Seddon I, Jabbehdari S, Singh RP. Optical coherence tomography angiography measurements in Parkinson's disease: A systematic review and meta-analysis. Eye (Lond) 2023; 37:3145-3156. [PMID: 36941403 PMCID: PMC10564940 DOI: 10.1038/s41433-023-02483-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 01/06/2023] [Accepted: 02/28/2023] [Indexed: 03/23/2023] Open
Abstract
Optical coherence tomography angiography (OCT-A) is an ocular imaging technology that has emerged as a non-invasive tool to evaluate retinal microvascular changes in neurodegenerative diseases including Parkinson's disease (PD) and Alzheimer's disease. While several studies have reported on the presence of pathologic retinal microvascular alterations in PD, the utility of OCT-A as a biomarker for PD evaluation is still unclear. A systematic review and meta-analysis were performed to explore the current evidence for the role of OCT-A in PD published up until June 2022. PubMed, Scopus, and Web of Science databases were used to systematically identify relevant papers and a meta-analysis was conducted using Stata16 software according to the level of heterogeneity applying a random- or fixed-effect model. Thirteen studies of 925 eyes in the PD group and 1501 eyes in the control group assessing OCT-A findings in PD patients were included. The meta-analyses revealed that the foveal region of PD patients had a significantly lower vessel density in the superficial capillary plexus (SCP) compared to healthy controls but that there were no significant differences in the foveal avascular zone, the SCP in whole, parafoveal, and perifoveal regions, and deep capillary plexus. OCT-A metrics may act as a potential biomarker for a more accurate and early PD diagnosis. Still, the OCT-A algorithms and interchangeability between OCT-A devices require further standardization to draw clinical conclusions regarding their utility.
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Affiliation(s)
| | - Fateme Rezagholi
- School of Medicine, Qazvin University of Medical Sciences, Qazvin, Iran
| | - Soheil Mohammadi
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Sina Zakavi
- School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Jahanshahi
- School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Mahdi Gouravani
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Ghasem Yazdanpanah
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, University of Illinois at Chicago, Chicago, IL, USA
| | - Ian Seddon
- College of Osteopathic Medicine, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Sayena Jabbehdari
- Jones Eye Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Rishi P Singh
- Center for Ophthalmic Bioinformatics, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA.
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16
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Sawaspadungkij M, Apinyawasisuk S, Suwan Y, Aghsaei Fard M, Sahraian A, Jalili J, Chansangpetch S. Disagreement of Radial Peripapillary Capillary Density Among Four Optical Coherence Tomography Angiography Devices. Transl Vis Sci Technol 2023; 12:7. [PMID: 37555736 PMCID: PMC10424153 DOI: 10.1167/tvst.12.8.7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 06/26/2023] [Indexed: 08/10/2023] Open
Abstract
Purpose This prospective study evaluated the agreement among four optical coherence tomography angiography (OCTA) devices in the assessment of radial peripapillary capillary (RPC) density. Methods The study included 48 eyes of 48 subjects (14 healthy, 19 glaucomatous, and 15 non-glaucomatous optic neuropathy). Each participant was scanned using four OCTA devices in a random sequence: RTVue XR Avanti (RTVue), DRI OCT Triton (Triton), Revo NX 130 (Revo), and PLEX Elite 9000 (PlexE). All 6 × 6-mm grayscale OCTA images from each device were analyzed for RPC density using a customized algorithm. Agreement between each pair of devices was assessed using intraclass correlation coefficients (ICCs) and Bland-Altman plots. Results There was a poor correlation between devices in all comparisons (RTVue-Triton, ICC = 0.34; RTVue-Revo, ICC = 0.31; RTVue-PlexE, ICC = 0.28; Triton-Revo, ICC = 0.31; Triton-PlexE, ICC = 0.17; Revo-PlexE, ICC = 0.34). Significant proportional biases (P < 0.05) and wide limits of agreement with apparent constant biases were identified in all comparisons. The mean difference was greatest for the RTVue-Revo pair (-49.3%; 95% confidence interval [CI], -52.9 to -45.8) and smallest for the Triton-PlexE pair (-7.7%; 95% CI, -10.1 to -5.3). Conclusions The RPC densities obtained from each device had poor inter-device agreement and significant biases and cannot be used interchangeably. Translational Relevance RPC density obtained from different OCTA devices is not interchangeable; thus, the progression of optic neuropathy should be monitored using the same OCTA device.
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Affiliation(s)
- Monchanok Sawaspadungkij
- Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Supanut Apinyawasisuk
- Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Yanin Suwan
- Department of Ophthalmology, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | | | - Alireza Sahraian
- Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Jalil Jalili
- Biomedical Engineering Unit, Cardiovascular Disease Research Center, Heshmat Hospital, Guilan University of Medical Sciences, Rasht, Iran
| | - Sunee Chansangpetch
- Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
- Center of Excellence in Glaucoma, Chulalongkorn University, Bangkok, Thailand
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17
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Gu X, Zhao X, Zhao Q, Wang Y, Chen Y. Recent Advances in Imaging Polypoidal Choroidal Vasculopathy with Swept-Source Optical Coherence Tomography Angiography. Diagnostics (Basel) 2023; 13:2458. [PMID: 37510200 PMCID: PMC10377931 DOI: 10.3390/diagnostics13142458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/27/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023] Open
Abstract
The gold standard for polypoidal choroidal vasculopathy (PCV) diagnosis is indocyanine green angiography (ICGA), but optical coherence tomography angiography (OCTA) has shown promise for PCV imaging in recent years. However, earlier generations of OCTA technology lacked the diagnostic efficacy to replace ICGA. Swept-source optical coherence tomography angiography (SS-OCTA), the latest generation of OCTA technology, has significantly improved penetrating ability, scanning speed, scanning range, and overall image quality compared with earlier generations of OCTA. SS-OCTA reveals a "tangled vasculature" pattern of polypoidal lesions (PLs), providing evidence that they are neovascular rather than aneurysmal structures. New choroidal biomarkers, such as the choriocapillaris flow void (FV), have been identified to explain the development of PCV lesions. Although no direct comparison between SS-OCTA and previous OCTA generations in terms of diagnostic capability has been performed, SS-OCTA has shown several advantages in differential diagnosis and monitoring early reactivation for PCV. These improvements make SS-OCTA a valuable tool for PCV diagnosis and follow-up, and it may become more important for this disease in the future. This review summarized recent advances in PCV morphology and structure, as well as the possible pathogenesis based on SS-OCTA findings. The value of SS-OCTA for PCV management is discussed, along with remaining issues, to provide an updated understanding of PCV and OCTA-guided management.
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Affiliation(s)
- Xingwang Gu
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Xinyu Zhao
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Qing Zhao
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Yuelin Wang
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Youxin Chen
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China
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18
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Park JB, Kim K, Kang MS, Kim ES, Yu SY. Optical coherence tomography angiography biomarkers in a bi-monthly maintenance dosing aflibercept in patients with neovascular age-related macular degeneration. BMC Ophthalmol 2023; 23:314. [PMID: 37438681 DOI: 10.1186/s12886-023-03039-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 06/12/2023] [Indexed: 07/14/2023] Open
Abstract
PURPOSE To evaluate the correlations between swept-source optical coherence tomography angiography (SS-OCTA) parameters and clinical outcomes in eyes with neovascular age-related macular degeneration (nAMD) administered a bimonthly intravitreal aflibercept regimen. METHODS This prospective, single-arm, interventional study enrolled 33 patients with treatment-naïve nAMD. The eyes received three monthly aflibercept injections followed by five bi-monthly regimens (total 50 weeks). The structural parameters including central subfield thickness (CST) and 5 mm pigment epithelial detachment (PED) volume and microvascular parameters including macular neovascularization (MNV) area, vessel density (VD), and vessel length density (VLD) were recorded every before and 1 week after treatment. RESULTS Patients who gained > 5 letters of best-corrected visual acuity (BCVA) from the baseline showed greater decreases in VD and VLD during the loading phase. Patients without recurrent or persistent fluid during the maintenance phase showed greater decreases in CST and 5 mm PED volume after the first injection. The decrease in mean VD during the loading phase was significantly correlated with the final BCVA (r = -0.820, p = 0.004). Moreover, the decrease in mean VLD during the loading phase was significantly correlated with the improvement in the final BCVA (r = -0.726, p = 0.017). CONCLUSIONS The decrease in mean VD during the loading phase was significantly negatively correlated with the final BCVA at the last visit. The decrease in mean VLD during the loading phase, mean CST during the loading phase, and the improvement in final BCVA showed significant correlations. Therefore, early changes in OCTA microvascular and OCT structural parameters could help predict clinical outcomes in nAMD. TRIAL REGISTRATION The trial was registered with the Clinical Research Information Service (CRIS), which joined the WHO International Clinical Trials Registry Platform (ICTRP) (Registration number: KCT0007375, Date of first trial registration: 10/06/2022).
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Affiliation(s)
- Jong Beom Park
- Department of Ophthalmology, Kyung Hee University Hospital, Kyung Hee University, 23, Kyungheedae-ro,, Dongdaemun-gu, Seoul, 02447, Republic of Korea
| | - Kiyoung Kim
- Department of Ophthalmology, Kyung Hee University Hospital, Kyung Hee University, 23, Kyungheedae-ro,, Dongdaemun-gu, Seoul, 02447, Republic of Korea
| | - Min Seok Kang
- Department of Ophthalmology, Kyung Hee University Hospital, Kyung Hee University, 23, Kyungheedae-ro,, Dongdaemun-gu, Seoul, 02447, Republic of Korea
| | - Eung Suk Kim
- Department of Ophthalmology, Kyung Hee University Hospital, Kyung Hee University, 23, Kyungheedae-ro,, Dongdaemun-gu, Seoul, 02447, Republic of Korea.
| | - Seung-Young Yu
- Department of Ophthalmology, Kyung Hee University Hospital, Kyung Hee University, 23, Kyungheedae-ro,, Dongdaemun-gu, Seoul, 02447, Republic of Korea.
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19
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Zhao T, Laotaweerungsawat S, Chen Y, Liu X, Liu D, Stewart JM. Right versus left eye asymmetry of microvasculature in diabetes revealed by optical coherence tomography angiography. Sci Rep 2023; 13:9332. [PMID: 37291258 PMCID: PMC10250307 DOI: 10.1038/s41598-023-36058-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 05/28/2023] [Indexed: 06/10/2023] Open
Abstract
In this study, we explored inter-ocular asymmetry (between the two eyes of the same patient) using optical coherence tomography angiography (OCTA) in patients with diabetes mellitus (DM) at different retinopathy stages. A total of 258 patients were divided into four groups: no DM, DM without diabetic retinopathy (DR), non-proliferative DR (NPDR), and proliferative DR (PDR). Superficial and deep vessel density (SVD, DVD), superficial and deep perfusion density (SPD, DPD), foveal avascular zone (FAZ) area, perimeter and circularity were calculated, and asymmetry index (AI) was used to evaluate the asymmetry of two eyes of the same subject. AIs of SPD, SVD, FAZ area and FAZ perimeter in the PDR group were larger than all other 3 groups (all p < 0.05). The AIs of DPD, DVD, FAZ area and FAZ perimeter in males were larger than in females (p = 0.015, p = 0.023, p = 0.006 and p = 0.017). Hemoglobin A1c (HbA1c) was positively correlated with AI of FAZ perimeter (p = 0.02) and circularity (p = 0.022). In conclusion, PDR patients' eyes were significantly asymmetric in both vascular density and FAZ metrics. Male sex and HbA1c are risk factors that influenced symmetry. This study highlights that right-left asymmetry should be taken into account in DR-related studies, particularly those analyzing microvascular changes with OCTA.
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Affiliation(s)
- Tong Zhao
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
- Department of Ophthalmology, Zuckerberg San Francisco General Hospital and Trauma Center, San Francisco, CA, USA
- Department of Ophthalmology, China-Japan Friendship Hospital, Beijing, China
| | - Sawarin Laotaweerungsawat
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
- Department of Ophthalmology, Zuckerberg San Francisco General Hospital and Trauma Center, San Francisco, CA, USA
- Department of Ophthalmology, Charoenkrung Pracharak Hospital, Bangkok, Thailand
| | - Yi Chen
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
- Department of Ophthalmology, Zuckerberg San Francisco General Hospital and Trauma Center, San Francisco, CA, USA
- Shenzhen Key Laboratory of Ophthalmology, Shenzhen Eye Hospital, Jinan University, Shenzhen, China
- School of Optometry, Shenzhen University, Shenzhen, China
| | - Xiuyun Liu
- Department of Physiological Nursing, University of California, San Francisco, San Francisco, CA, USA
| | - Dongwei Liu
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA
- Department of Ophthalmology, Zuckerberg San Francisco General Hospital and Trauma Center, San Francisco, CA, USA
- Department of Ophthalmology, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jay M Stewart
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA.
- Department of Ophthalmology, Zuckerberg San Francisco General Hospital and Trauma Center, San Francisco, CA, USA.
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20
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Bostan M, Pîrvulescu R, Tiu C, Bujor I, Popa-Cherecheanu A. OCT and OCT-A biomarkers in multiple sclerosis - review. Rom J Ophthalmol 2023; 67:107-110. [PMID: 37522023 PMCID: PMC10385714 DOI: 10.22336/rjo.2023.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2023] [Indexed: 08/01/2023] Open
Abstract
Objective: Retinal neuronal and vascular changes have been observed in multiple sclerosis (MS) patients. The aim of this review was to highlight the most current optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A) data in MS and to provide information about the possibility of using OCT / OCT-A parameters as biomarkers for screening, diagnosis and monitoring of MS. Methods: To carry out this review, a meticulous literature search was undergone on PubMed between 2014 and the present day, using the following terms: "multiple", "sclerosis", "optical", "coherence", "tomography" and "angiography". Additional studies were found via references, being chosen according to relevance. Results: Retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) were significantly lower in MS patients compared to controls, and correlated with clinical and paraclinical variables, such as visual function, disability, and magnetic resonance imaging (MRI). Retinal capillary plexuses could be higher, lower or the same, and the best OCT-A microvasculature parameter for the detection of MS was the superficial capillary plexus (SCP). The reduced retinal vessel density (VD) was correlated with the disability in MS. Conclusions: OCT and OCT-A parameters could improve the development of retinal biomarkers for screening, early diagnosis and monitoring the disease progression of MS, and they could improve the development of potential future therapies that could slow or stop the course of this incurable disease. Abbreviations: DCP = deep capillary plexus; EDSS = Expanded Disability Status Scale; GCC = ganglion cell complex; GCL = ganglion cell layer; MRI = magnetic resonance imaging; MS = Multiple sclerosis; OCT = optical coherence tomography; OCT-A = optical coherence tomography angiography; ON = optic neuritis; RNFL = retinal nerve fiber layer; SCP = superficial capillary plexus; VD = vessel density.
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Affiliation(s)
- Mihai Bostan
- “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
- Ophthalmology Emergency Hospital, Bucharest, Romania
| | - Ruxandra Pîrvulescu
- “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, University Emergency Hospital, Bucharest, Romania
| | - Cristina Tiu
- “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
- Department of Neurology, University Emergency Hospital, Bucharest, Romania
| | - Inna Bujor
- “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - Alina Popa-Cherecheanu
- “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
- Department of Ophthalmology, University Emergency Hospital, Bucharest, Romania
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21
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Richter GM, Lee JC, Khan N, Vorperian A, Hand B, Burkemper B, Zhou X, Chu Z, Wang R, Varma R, Kashani AH. Ocular and systemic determinants of perifoveal and macular vessel parameters in healthy African Americans. Br J Ophthalmol 2023; 107:540-546. [PMID: 34740885 DOI: 10.1136/bjophthalmol-2021-319675] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 10/18/2021] [Indexed: 01/17/2023]
Abstract
PURPOSE To determine the relationship of various systemic and ocular characteristics with perifoveal and macular vessel density in healthy African American eyes. DESIGN A population-based cross-sectional study of prospectively recruited African Americans ≥40 years of age. Participants underwent 3×3 mm and 6×6 mm macula scans using spectral-domain optical coherence tomography angiography (OCTA), clinical examinations and clinical questionnaires. Participants with glaucoma, severe non-proliferative diabetic retinopathy, proliferative diabetic retinopathy and macular oedema were excluded. Custom MATLAB based software quantified vessel area density (VAD) and vessel skeleton density (VSD) in the superficial retinal layer of the macula. Multivariable regression analysis, controlling for inter-eye correlation, was performed to determine systemic and ocular determinants of macular vessel metrics using stepwise selection. Candidate variables included: age, gender, body mass index, history of smoking, history of diabetes, diabetes duration, history of stroke or brain haemorrhage, systolic blood pressure, diastolic blood pressure (DBP), pulse pressure, mean arterial pressure, central subfield thickness (CSFT), visual field mean deviation, intraocular pressure, axial length (AL), mean ocular perfusion pressure and signal strength (SS). RESULTS A total of 2221 OCTA imaged eyes from 1472 participants were included in this study. Reduced perifoveal and macular VAD and VSD were independently associated with longer AL, reduced SS, reduced CSFT and older age. Male gender and lower DBP were also associated with reduced perifoveal and macular VSD. CONCLUSIONS When interpreting OCTA images in a clinical setting, it is important to consider the effects ocular and systemic characteristics may have on the macular microcirculation.
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Affiliation(s)
- Grace M Richter
- Ophthalmology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Jae Chang Lee
- Ophthalmology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Nasir Khan
- Ophthalmology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Alexander Vorperian
- Ophthalmology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Brennan Hand
- Ophthalmology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Bruce Burkemper
- Ophthalmology, University of Southern California Keck School of Medicine, Los Angeles, California, USA
| | - Xiao Zhou
- Bioengineering, University of Washington, Seattle, Washington, USA
| | - Zhongdi Chu
- Bioengineering, University of Washington, Seattle, Washington, USA
| | - Ruikang Wang
- Bioengineering, University of Washington, Seattle, Washington, USA
| | - Rohit Varma
- Southern California Eye Institute, Los Angeles, California, USA
| | - Amir H Kashani
- Department of Ophthalmology, Johns Hopkins University, Baltimore, Maryland, USA
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22
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Lee YJ, Sun S, Kim YK, Jeoung JW, Park KH. Diagnostic ability of macular microvasculature with swept-source OCT angiography for highly myopic glaucoma using deep learning. Sci Rep 2023; 13:5209. [PMID: 36997639 PMCID: PMC10063664 DOI: 10.1038/s41598-023-32164-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 03/23/2023] [Indexed: 04/01/2023] Open
Abstract
Macular OCT angiography (OCTA) measurements have been reported to be useful for glaucoma diagnostics. However, research on highly myopic glaucoma is lacking, and the diagnostic value of macular OCTA measurements versus OCT parameters remains inconclusive. We aimed to evaluate the diagnostic ability of the macular microvasculature assessed with OCTA for highly myopic glaucoma and to compare it with that of macular thickness parameters, using deep learning (DL). A DL model was trained, validated and tested using 260 pairs of macular OCTA and OCT images from 260 eyes (203 eyes with highly myopic glaucoma, 57 eyes with healthy high myopia). The DL model achieved an AUC of 0.946 with the OCTA superficial capillary plexus (SCP) images, which was comparable to that with the OCT GCL+ (ganglion cell layer + inner plexiform layer; AUC, 0.982; P = 0.268) or OCT GCL++ (retinal nerve fiber layer + ganglion cell layer + inner plexiform layer) images (AUC, 0.997; P = 0.101), and significantly superior to that with the OCTA deep capillary plexus images (AUC, 0.779; P = 0.028). The DL model with macular OCTA SCP images demonstrated excellent and comparable diagnostic ability to that with macular OCT images in highly myopic glaucoma, which suggests macular OCTA microvasculature could serve as a potential biomarker for glaucoma diagnosis in high myopia.
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Affiliation(s)
- Yun Jeong Lee
- Department of Ophthalmology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Sukkyu Sun
- Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Young Kook Kim
- Department of Ophthalmology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jin Wook Jeoung
- Department of Ophthalmology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Ki Ho Park
- Department of Ophthalmology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
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23
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Girgis JM, Saukkonen D, Hüther A, Alibhai AY, Moult EM, Abu-Qamar O, Fujimoto JG, Baumal CR, Witkin AJ, Duker JS, Waheed NK. Optical Coherence Tomography Angiography Analysis Toolbox: A Repeatable and Reproducible Software Tool for Quantitative Optical Coherence Tomography Angiography Analysis. Ophthalmic Surg Lasers Imaging Retina 2023; 54:114-122. [PMID: 36780632 DOI: 10.3928/23258160-20230206-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
BACKGROUND AND OBJECTIVE The purpose of this article is to demonstrate the optical coherence tomography angiography (OCTA) Analysis Toolkit (OAT), a custom-designed software package, as a repeatable and reproducible tool for computing OCTA metrics across different devices. MATERIALS AND METHODS Fourteen participants were imaged using three devices. Foveal avascular zone, vessel index, vessel length index, and vessel diameter index were calculated using the OAT. Repeatability and reproducibility were assessed using the coefficient of variation and interclass correlation coefficient (ICC). RESULTS Analysis of identical images demonstrated perfect levels of repeatability for all metrics (coefficient of variation 0%), which was a consequence of the software being deterministic (ie, producing the same outputs for the same inputs). Foveal avascular zone ICC values were in the excellent-to-good range (ICC > 0.6) for all devices. All values for vessel index (VI), vessel length index, and vessel diameter index fell in the good-to-fair (ICC > 0.4) or excellent-to-good range, except for vessel index analysis in the Cirrus device (ICC = 0.34). CONCLUSIONS The OAT appears to be a reliable tool that may enable comparison between OCTA data sets acquired on different imaging instruments, thereby facilitating a more consistent approach to OCTA analysis. [Ophthalmic Surg Lasers Imaging Retina 2023;54:114-122.].
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Deep Learning in Optical Coherence Tomography Angiography: Current Progress, Challenges, and Future Directions. Diagnostics (Basel) 2023; 13:diagnostics13020326. [PMID: 36673135 PMCID: PMC9857993 DOI: 10.3390/diagnostics13020326] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
Optical coherence tomography angiography (OCT-A) provides depth-resolved visualization of the retinal microvasculature without intravenous dye injection. It facilitates investigations of various retinal vascular diseases and glaucoma by assessment of qualitative and quantitative microvascular changes in the different retinal layers and radial peripapillary layer non-invasively, individually, and efficiently. Deep learning (DL), a subset of artificial intelligence (AI) based on deep neural networks, has been applied in OCT-A image analysis in recent years and achieved good performance for different tasks, such as image quality control, segmentation, and classification. DL technologies have further facilitated the potential implementation of OCT-A in eye clinics in an automated and efficient manner and enhanced its clinical values for detecting and evaluating various vascular retinopathies. Nevertheless, the deployment of this combination in real-world clinics is still in the "proof-of-concept" stage due to several limitations, such as small training sample size, lack of standardized data preprocessing, insufficient testing in external datasets, and absence of standardized results interpretation. In this review, we introduce the existing applications of DL in OCT-A, summarize the potential challenges of the clinical deployment, and discuss future research directions.
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25
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Häner NU, Dysli C, Munk MR. Imaging in retinal vascular disease: A review. Clin Exp Ophthalmol 2023; 51:217-228. [PMID: 36597823 DOI: 10.1111/ceo.14203] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/06/2022] [Accepted: 12/09/2022] [Indexed: 01/05/2023]
Abstract
Retinal vascular diseases represent a broad field of ocular pathologies. Retinal imaging is an important tool for diagnosis, prognosis and follow up of retinal vascular diseases. It includes a wide variety of imaging techniques ranging from colour fundus photography and optical coherence tomography to dynamic diagnostic options such as fluorescein angiography, and optical coherence tomography angiography. The newest developments in respective imaging techniques include widefield imaging to assess the retinal periphery, which is of especial interest in retinal vascular diseases. Automatic image analysis and artificial intelligence may support the image analysis and may prove valuable for prognostic purposes. This review provides a broad overview of the imaging techniques that have been used in the past, today and maybe in the future to stage and monitor retinal vascular disease with focus on the main disease entities including diabetic retinopathy, retinal vein occlusion, and retinal artery occlusion.
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Affiliation(s)
- Nathanael U Häner
- Department of Ophthalmology, Inselspital University Hospital, Bern, Switzerland
| | - Chantal Dysli
- Department of Ophthalmology, Inselspital University Hospital, Bern, Switzerland
| | - Marion R Munk
- Department of Ophthalmology, Inselspital University Hospital, Bern, Switzerland
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26
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Nam KY, Lee MW, Lee KH, Kim JY. Superficial capillary plexus vessel density/deep capillary plexus vessel density ratio in healthy eyes. BMC Ophthalmol 2022; 22:482. [PMID: 36494798 PMCID: PMC9733217 DOI: 10.1186/s12886-022-02673-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 11/05/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND To identify factors differently affecting the superficial capillary plexus (SCP) and deep capillary plexus (DCP) in healthy eyes using their vessel density (VD) ratio. METHODS Healthy eyes were enrolled. The ratio between the VD of SCP and DCP (SVD/DVD ratio) was calculated. Pearson correlation analyses were performed to identify the relationships between this ratio and other factors. RESULTS The mean SVD and DVD were 36.2 ± 5.7 and 37.7 ± 4.9%, respectively, and the mean SVD/DVD ratio was 0.96 ± 0.15. The SVD was significantly correlated with the best-corrected visual acuity (BCVA) (r = - 0.368, P < 0.001), age (r = - 0.408, P < 0.001), and OCTA quality (r = 0.520, P < 0.001). The DVD was significantly correlated with the BCVA (r = - 0.150, P = 0.008), age (r = - 0.229, P < 0.001), and OCTA quality (r = 0.555, P < 0.001). Among various factors, age (r = - 0.296, P < 0.001), the BCVA (r = - 0.237, P < 0.001), axial length (r = 0.234, P < 0.001), and OCTA quality (r = 0.270, P < 0.001) were significantly correlated with the SVD/DVD ratio. CONCLUSIONS Age, BCVA, axial length, and OCTA image quality were significantly correlated with the SVD/DVD ratio. Age, the BCVA, and OCTA quality were more strongly correlated with the SCP, and the axial length was more strongly correlated with the DCP.
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Affiliation(s)
- Ki-Yup Nam
- grid.254230.20000 0001 0722 6377Department of Ophthalmology, Chungnam National University Sejong Hospital, Daejeon, Republic of Korea
| | - Min-Woo Lee
- grid.411143.20000 0000 8674 9741Department of Ophthalmology, Konyang University College of Medicine, #1643 Gwanjeo-dong, Seo-gu, Daejeon, South Korea
| | - Kook-Hyung Lee
- grid.411143.20000 0000 8674 9741Department of Ophthalmology, Konyang University College of Medicine, #1643 Gwanjeo-dong, Seo-gu, Daejeon, South Korea
| | - Jung-Yeul Kim
- grid.254230.20000 0001 0722 6377Department of Ophthalmology, Chungnam National University College of Medicine, #640 Daesa-dong, Jung-gu, Daejeon, 301-721 South Korea ,1.0 Eye clinic, Daejeon, Republic of Korea
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27
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Oliverio GW, Meduri A, De Salvo G, Trombetta L, Aragona P. OCT Angiography Features in Diabetes Mellitus Type 1 and 2. Diagnostics (Basel) 2022; 12:diagnostics12122942. [PMID: 36552948 PMCID: PMC9777069 DOI: 10.3390/diagnostics12122942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/16/2022] [Accepted: 11/22/2022] [Indexed: 11/26/2022] Open
Abstract
Purpose: To study the foveal avascular zone (FAZ) and the vessel densities (VD) in diabetic patients using optical coherence tomography angiography (OCT-A) and inner retinal layer changes to compare patients affected by type 1 diabetes (DM1) and type 2 diabetes (DM2). Methods: Cross-sectional observational study involving 150 eyes of 150 patients with DM1, and 155 eyes of 155 patients with DM2 with diabetic retinopathy (DR). Retinal nerve fiber layer (RNFL) and Ganglion cell layer (GCL) were evaluated. OCT-A studied both FAZ and VD at the level of the superficial capillary plexus (SCP) and the deep capillary plexus (DCP). Results: A statistically significant difference in FAZ area and foveal VD measured at the SCP (p < 0.001) was noted between DM1 and DM2 groups when comparing patients with mild and moderate non-proliferative diabetic retinopathy (NPDR), while no differences were found in the severe NPDR and proliferative diabetic retinopathy (PDR) subgroups. Duration of diabetes and stage of DR were directly correlated with enlargement of FAZ area and inversely correlated with foveal VD measured at SCP. RNFL and GCL were not different between DM1 and DM2 groups. Conclusion: Changes in OCT-A parameters detected in FAZ area and VD of diabetic patients with different stages of DR may help to predict the risk for progression of the disease.
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Affiliation(s)
| | - Alessandro Meduri
- Department of Biomedical Science, Ophthalmology Clinic, University of Messina, 98124 Messina, Italy
- Correspondence: ; Tel.: +39-09022173
| | - Gabriella De Salvo
- Ophthalmology Department, University Hospital Southampton, Southampton SO16 5YA, UK
| | - Luigi Trombetta
- Department of Biomedical Science, Ophthalmology Clinic, University of Messina, 98124 Messina, Italy
| | - Pasquale Aragona
- Department of Biomedical Science, Ophthalmology Clinic, University of Messina, 98124 Messina, Italy
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Ripolles-Garcia A, Chen Y, Sato Y, Gray A, Ying GS, Aguirre GD, Beltran WA. Retinal Vascular Plexuses Are Unequally Affected in Canine Inherited Retinal Degenerations. Invest Ophthalmol Vis Sci 2022; 63:22. [PMID: 36378130 PMCID: PMC9672900 DOI: 10.1167/iovs.63.12.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Purpose To characterize the progression of vascular changes that occur in each retinal plexus, in three canine models of inherited retinal degeneration. Methods In this retrospective cohort study, we examined the retinal imaging records of 44 dogs from a research colony that had undergone optical coherence tomography angiography (OCTA) imaging. Animals enrolled included crd2/NPHP5 and xlpra2/RPGR mutant dogs imaged at different stages of photoreceptor loss, as well as RHOT4R/+ dogs after acute light-induced rod degeneration. Also included were normal controls imaged at similar ages. OCT angiograms of the superficial vascular plexus combined with the intermediate capillary plexus (SVP + ICP), and the deep capillary plexus (DCP) were analyzed using the AngioTool software to calculate vessel density and other vascular parameters. Results A reduction in vessel density was seen over time in both the SVP + ICP and DCP in all mutant dogs but was more pronounced in the DCP. Scans were subclassified based on outer nuclear layer (ONL) thinning compared to age-matched normal controls. When ONL loss was 0% to 50%, vessel density in the DCP was significantly lower than in age-matched controls. In all cases, when ONL loss exceeded 87.5%, vessel density in the SVP + ICP was significantly reduced as well. In the acute light-induced rod degeneration model, the vascular regression changes were observed mainly in the DCP. Conclusions Vessel density reduction in dogs undergoing retinal degeneration is first detected by OCTA in the DCP, and only at later stages in the SVP + ICP.
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Affiliation(s)
- Ana Ripolles-Garcia
- Division of Experimental Retinal Therapies, Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Yineng Chen
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Yu Sato
- Division of Experimental Retinal Therapies, Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Alexa Gray
- Division of Experimental Retinal Therapies, Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Gui-Shuang Ying
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Gustavo D. Aguirre
- Division of Experimental Retinal Therapies, Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - William A. Beltran
- Division of Experimental Retinal Therapies, Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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Rajesh A, Droho S, Lavine JA. Macrophages in close proximity to the vitreoretinal interface are potential biomarkers of inflammation during retinal vascular disease. J Neuroinflammation 2022; 19:203. [PMID: 35941655 PMCID: PMC9361599 DOI: 10.1186/s12974-022-02562-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 07/29/2022] [Indexed: 12/21/2022] Open
Abstract
Background Diabetic retinopathy and retinal vein occlusion are vision threatening retinal vascular diseases. Current first-line therapy targets the vascular component, but many patients are treatment-resistant due to unchecked inflammation. Non-invasive inflammatory imaging biomarkers are a significant unmet clinical need for patients. Imaging of macrophage-like cells on the surface of the retina using clinical optical coherence tomography (OCT) is an emerging field. These cells are increased in patients with retinal vascular disease, and could be a potential inflammatory biomarker. However, since OCT is limited by an axial resolution of 5–10 microns, the exact location and identity of these retinal cells is currently unknown. Methods We performed OCT followed by confocal immunofluorescence in wild-type mice to identify macrophages within 5–10 microns of the vitreoretinal interface. Next, we used Cx3cr1CreER/+; Rosa26zsGreen/+ mice to fate map retinal surface macrophages. Using confocal immunofluorescence of retinal sections and flatmounts, we quantified IBA1+Tmem119+CD169neg microglia, IBA1+Tmem119negCD169neg perivascular macrophages, and IBA1+Tmem119negCD169+ vitreal hyalocytes. Finally, we modeled neuroinflammation with CCL2 treatment and characterized retinal surface macrophages using flow cytometry, OCT, and confocal immunofluorescence. Results We were able to detect IBA1+ macrophages within 5–10 microns of the vitreoretinal interface in wild-type mice using OCT followed by confirmatory confocal immunofluorescence. Retinal surface macrophages were 83.5% GFP+ at Week 1 and 82.4% GFP+ at Week 4 using fate mapping mice. At steady state, these macrophages included 82% IBA1+Tmem119+CD169neg microglia, 9% IBA1+Tmem119negCD169+ vitreal hyalocytes, and 9% IBA1+Tmem119negCD169neg perivascular macrophages. After CCL2-driven neuroinflammation, many Ly6C+ cells were detectable on the retinal surface using OCT followed by confocal immunofluorescence. Conclusions Macrophages within close proximity to the vitreoretinal interface are self-renewing cells, and predominantly microglia with minor populations of perivascular macrophages and vitreal hyalocytes at steady state. In the context of neuroinflammation, monocytes and monocyte-derived macrophages are a significant component of retinal surface macrophages. Human OCT-based imaging of retinal surface macrophages is a potential biomarker for inflammation during retinal vascular disease. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02562-3.
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Affiliation(s)
- Amrita Rajesh
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, 240 E Huron St, McGaw M343, Chicago, IL, 60611, USA
| | - Steven Droho
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, 240 E Huron St, McGaw M343, Chicago, IL, 60611, USA
| | - Jeremy A Lavine
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, 240 E Huron St, McGaw M343, Chicago, IL, 60611, USA.
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Pastore MR, Grotto A, Vezzoni F, Gaggino A, Milan S, Gouigoux S, Guerin PL, Vinciguerra AL, Cirigliano G, Tognetto D. Reproducibility and Reliability of Spectralis II OCT Angiography Vascular Measurements. Diagnostics (Basel) 2022; 12:diagnostics12081908. [PMID: 36010258 PMCID: PMC9406840 DOI: 10.3390/diagnostics12081908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 07/28/2022] [Accepted: 08/02/2022] [Indexed: 11/29/2022] Open
Abstract
Purpose: to investigate the reproducibility and reliability of OCT-A vascular measurements using Heidelberg Spectralis II OCT-A. Methods: a prospective study involving a single eye of patients aged 18 or older with no ocular disease. In order to investigate the reliability of the first and second OCT-A scans, the coefficient of variation of the foveal avascular zone (FAZ) and the vessel density (VD) in the superficial (SCP), intermediate (ICP) and deep capillary plexus (DCP) were calculated. Results: A total of 75 eyes were included in the study. The mean FAZ in the first and second scan was 0.36 × 0.13 mm2 and 0.37 × 0.12 mm2, respectively, in the SCP, 0.23 × 0.10 mm2 and 0.23 × 0.09 mm2 in the ICP, and 0.42 × 0.11 mm2 and 0.43 × 0.12 mm2 in the DCP. The overall VD was 36.05 × 9.01 and 35.33 × 9.92 at the first and second scan, respectively, in the SCP, 21.87 × 5.00 and 21.32 × 5.56 in the ICP, and 23.84 × 6.53 and 23.20 × 6.83 in the DCP. No statistically significant differences in FAZ measurements and VD in all sectors of each capillary plexus were observed between the first and second scan (p > 0.05). Conclusion: our study demonstrated the good reproducibility and reliability of OCT-A vascular measurements in the analysis of the FAZ and the quantification of VD in each capillary plexus of the retina.
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Microvascular changes in the macular and parafoveal areas of multiple sclerosis patients without optic neuritis. Sci Rep 2022; 12:13366. [PMID: 35922463 PMCID: PMC9349324 DOI: 10.1038/s41598-022-17344-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 07/25/2022] [Indexed: 02/08/2023] Open
Abstract
Retinal imaging has been proposed as a biomarker for neurological diseases such as multiple sclerosis (MS). Recently, a technique for non-invasive assessment of the retinal microvasculature called optical coherence tomography angiography (OCTA) was introduced. We investigated retinal microvasculature alterations in participants with relapsing–remitting MS (RRMS) without history of optic neuritis (ON) and compared them to a healthy control group. The study was performed in a prospective, case–control design, including 58 participants (n = 100 eyes) with RRMS without ON and 78 age- and sex-matched control participants (n = 136 eyes). OCTA images of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC) were obtained using a commercial OCTA system (Zeiss Cirrus HD-5000 Spectral-Domain OCT with AngioPlex OCTA, Carl Zeiss Meditec, Dublin, CA). The outcome variables were perfusion density (PD) and foveal avascular zone (FAZ) features (area and circularity) in both the SCP and DCP, and flow deficit in the CC. MS group had on average higher intraocular pressure (IOP) than controls (P < 0.001). After adjusting for confounders, MS participants showed significantly increased PD in SCP (P = 0.003) and decreased PD in DCP (P < 0.001) as compared to controls. A significant difference was still noted when large vessels (LV) in the SCP were removed from the PD calculation (P = 0.004). Deep FAZ was significantly larger (P = 0.005) and less circular (P < 0.001) in the eyes of MS participants compared to the control ones. Neither LV, PD or FAZ features in the SCP, nor flow deficits in the CC showed any statistically significant differences between the MS group and control group (P > 0.186). Our study indicates that there are microvascular changes in the macular parafoveal retina of RRMS patients without ON, showing increased PD in SCP and decreased PD in DCP. Further studies with a larger cohort of MS patients and MRI correlations are necessary to validate retinal microvascular changes as imaging biomarkers for diagnosis and screening of MS.
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Law VK, Lam AK. Effect of caffeine on superficial retinal vasculature of the macula in high myopes using optical coherence tomography angiography - A pilot study. JOURNAL OF OPTOMETRY 2022; 15:210-218. [PMID: 35637106 PMCID: PMC9237592 DOI: 10.1016/j.optom.2021.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/13/2021] [Accepted: 06/18/2021] [Indexed: 06/15/2023]
Abstract
PURPOSE To monitor effect of caffeine on vasculature of the inner retina of high myopes METHODS: This was a crossover, self-control, randomized trial. Healthy young high myopes were recruited to take 200 mg of caffeine capsule and placebo capsule, randomly assigned in two visits separated by at least one week. Superficial retinal vasculature in terms of vessel length density (VD) and perfusion area density (PD) was captured and monitored using a spectral domain optical coherence tomography angiography (OCTA) machine. After baseline measurements, blood pressure (BP), intraocular pressure (IOP), and subfoveal choroidal thickness (ChT) were also monitored at 30-min intervals till 3 h. RESULTS Eighteen subjects (6 male, 24.3 ± 3.1 years) completed the study. After taking the caffeine capsule, there was a significant increase in BP (p < 0.01), and reduction in ChT (p < 0.01), with no change in IOP (p = 0.36). VD demonstrated a trend of reduction at the central 1-mm circle, and 1-3 mm annulus (p < 0.01) following the ETDRS grid. Reduction trend of PD appeared at the central 1-mm circle, 1-3 mm annulus, and the entire 3-mm circle (p < 0.01). Compared with baseline, VD and PD reductions were significant 180 min after taking the caffeine capsule at the central 1-mm circle, but the reduction was small (VD: by 1mm-1; PD: by 1%). Changes in other regions were not significant. CONCLUSIONS The current study found significant reduction in VD and PD after taking 200 mg of caffeine capsule. Such a small amount of alteration may be clinically irrelevant.
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Affiliation(s)
- Victoria Km Law
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - Andrew Kc Lam
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong SAR, China.
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Cheung CMG, Fawzi A, Teo KY, Fukuyama H, Sen S, Tsai WS, Sivaprasad S. Diabetic macular ischaemia- a new therapeutic target? Prog Retin Eye Res 2022; 89:101033. [PMID: 34902545 PMCID: PMC11268431 DOI: 10.1016/j.preteyeres.2021.101033] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 11/25/2021] [Accepted: 12/01/2021] [Indexed: 12/21/2022]
Abstract
Diabetic macular ischaemia (DMI) is traditionally defined and graded based on the angiographic evidence of an enlarged and irregular foveal avascular zone. However, these anatomical changes are not surrogate markers for visual impairment. We postulate that there are vascular phenotypes of DMI based on the relative perfusion deficits of various retinal capillary plexuses and choriocapillaris. This review highlights several mechanistic pathways, including the role of hypoxia and the complex relation between neurons, glia, and microvasculature. The current animal models are reviewed, with shortcomings noted. Therefore, utilising the advancing technology of optical coherence tomography angiography (OCTA) to identify the reversible DMI phenotypes may be the key to successful therapeutic interventions for DMI. However, there is a need to standardise the nomenclature of OCTA perfusion status. Visual acuity is not an ideal endpoint for DMI clinical trials. New trial endpoints that represent disease progression need to be developed before irreversible vision loss in patients with DMI. Natural history studies are required to determine the course of each vascular and neuronal parameter to define the DMI phenotypes. These DMI phenotypes may also partly explain the development and recurrence of diabetic macular oedema. It is also currently unclear where and how DMI fits into the diabetic retinopathy severity scales, further highlighting the need to better define the progression of diabetic retinopathy and DMI based on both multimodal imaging and visual function. Finally, we discuss a complete set of proposed therapeutic pathways for DMI, including cell-based therapies that may provide restorative potential.
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Affiliation(s)
- Chui Ming Gemmy Cheung
- Singapore Eye Research Institution, Singapore National Eye Centre, Singapore; Duke-NUS Medical School, National University of Singapore, Singapore
| | | | - Kelvin Yc Teo
- Singapore Eye Research Institution, Singapore National Eye Centre, Singapore
| | | | | | - Wei-Shan Tsai
- NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, United Kingdom
| | - Sobha Sivaprasad
- NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, United Kingdom.
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Multi-modal and multi-scale clinical retinal imaging system with pupil and retinal tracking. Sci Rep 2022; 12:9577. [PMID: 35688890 PMCID: PMC9187716 DOI: 10.1038/s41598-022-13631-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 05/17/2022] [Indexed: 11/08/2022] Open
Abstract
We present a compact multi-modal and multi-scale retinal imaging instrument with an angiographic functional extension for clinical use. The system integrates scanning laser ophthalmoscopy (SLO), optical coherence tomography (OCT) and OCT angiography (OCTA) imaging modalities and provides multi-scale fields of view. For high resolution, and high lateral resolution in particular, cellular imaging correction of aberrations by adaptive optics (AO) is employed. The entire instrument has a compact design and the scanning head is mounted on motorized translation stages that enable 3D self-alignment with respect to the subject's eye by tracking the pupil position. Retinal tracking, based on the information provided by SLO, is incorporated in the instrument to compensate for retinal motion during OCT imaging. The imaging capabilities of the multi-modal and multi-scale instrument were tested by imaging healthy volunteers and patients.
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Kumawat D, Chawla R, Shah P, Sharma A, Sachan A, Pandey V. Automated and ImageJ thresholding algorithm-based analysis of macular vessel density in diabetic patients. Indian J Ophthalmol 2022; 70:2050-2056. [PMID: 35647980 PMCID: PMC9359289 DOI: 10.4103/ijo.ijo_74_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Purpose: To assess the macular vessel density (VD) on optical coherence tomography angiography (OCT-A) using proprietary software (automated) and image processing software (manual) in diabetic patients. Methods: In a retrospective study, OCT-A images (Triton, TOPCON Inc.) of type 2 diabetics presenting to a tertiary eye care center in North India between January 2018 and December 2019 with or without nonproliferative diabetic retinopathy (NPDR) and with no macular edema were analyzed. Macular images of size 3 × 3 mm were binarized with global thresholding algorithms (ImageJ software). Outcome measures were superficial capillary plexus VD (SCP-VD, automated and manual), deep capillary plexus VD (DCP-VD, manual), and correlation between automated and manual SCP-VD. Results: OCT-A images of 89 eyes (55 patients) were analyzed: no diabetic retinopathy (NoDR): 29 eyes, mild NPDR: 29 eyes, and moderate NPDR: 31 eyes. Automated SCP-VD did not differ between NoDR and mild NPDR (P = 0.69), but differed between NoDR and moderate NPDR (P = 0.014) and between mild and moderate NPDR (P = 0.033). Manual SCP-VD (Huang and Otsu methods) did not differ between the groups. Manual DCP-VD differed between NoDR and mild NPDR and between NoDR and moderate NPDR, but not between mild and moderate NPDR with both Huang (P = 0.024, 0.003, and 0.51, respectively) and Otsu (P = 0.021, 0.006, and 0.43, respectively) methods. Automated SCP-VD correlated moderately with manual SCP-VD using Huang method (r = 0.51, P < 0.001) with a mean difference of −0.01% (agreement limits from −6.60% to +6.57%). Conclusion: DCP-VD differs consistently between NoDR and NPDR with image processing, while SCP-VD shows variable results. Different thresholding algorithms provide different results, and there is a need to establish consensus on the most suited algorithm.
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Affiliation(s)
- Devesh Kumawat
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Rohan Chawla
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Pooja Shah
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Anu Sharma
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Anusha Sachan
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Veena Pandey
- Department of Biostatistics, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
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Tian M, Zeng G, Tappeiner C, Zinkernagel MS, Wolf S, Munk MR. Comparison of Indocyanine Green Angiography and Swept-Source Wide-Field Optical Coherence Tomography Angiography in Posterior Uveitis. Front Med (Lausanne) 2022; 9:853315. [PMID: 35586074 PMCID: PMC9108898 DOI: 10.3389/fmed.2022.853315] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 04/04/2022] [Indexed: 11/22/2022] Open
Abstract
Purpose To compare indocyanine green angiography (ICGA) and swept-source wide-field optical coherence tomography angiography (SS-OCTA) for the assessment of patients with posterior uveitis. Method SS-OCTA montage images of 5 x 12 x 12 mm or 2 x 15 x 9 mm, covering ~70-90 degree of the retina of consecutive patients with posterior uveitis were acquired. The choriocapillaries and choroidal slabs were compared to findings on ICGA. Results Sixty-eight eyes of 41 patients were included (mean age 47.2 ± 20.4 years; 58.5% female). In 23 (34%) lesions were visible on OCTA, but not discernable on ICGA. In turn, out of the 45 eyes with clearly discernable lesions on ICGA, 22 (49%) and 21 (47%) eyes showed no corresponding areas of flow deficit on OCTA in the CC and choroidal slab, respectively. Lesion size strongly correlated among ICGA and OCTA choriocapillaries- (CC) (r = 0.99, p ≤ 0.0001) and choroidal slabs (r = 0.99, p ≤ 0.0001), respectively. The mean lesion size on the late frames of ICGA (8.45 ± 5.47 mm2) was larger compared to the lesion size on OCTA CC scan (7.98 ± 5.47 mm2, p ≤ 0.0001) and choroidal scan (7.69 ± 5.10 mm2, p = 0.002), respectively. The lesion size on OCTA CC scan was significantly larger than on the OCTA choroidal scan (p ≤ 0.0001). Conclusion SS-wide field OCTA may be a promising tool to assess posterior uveitis patients and may replace ICGA to a certain extent in the future.
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Affiliation(s)
- Meng Tian
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Bern Photographic Reading Center, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Guodong Zeng
- SITEM Center for Translational Medicine and Biomedical Entrepreneurship, University of Bern, Bern, Switzerland
| | - Christoph Tappeiner
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Ophthalmology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
- Pallas Klinik, Olten, Switzerland
| | - Martin S. Zinkernagel
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Sebastian Wolf
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Bern Photographic Reading Center, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Marion R. Munk
- Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Bern Photographic Reading Center, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
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Yeh TC, Kuo CT, Chou YB. Retinal Microvascular Changes in Mild Cognitive Impairment and Alzheimer's Disease: A Systematic Review, Meta-Analysis, and Meta-Regression. Front Aging Neurosci 2022; 14:860759. [PMID: 35572135 PMCID: PMC9096234 DOI: 10.3389/fnagi.2022.860759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 03/14/2022] [Indexed: 01/03/2023] Open
Abstract
Background The remarkable increase in prevalence and significant morbidity of neurodegenerative diseases pose a tremendous burden for the health care system. Changes in retinal microvasculature metrics associated with Alzheimer's disease (AD) and mild cognitive impairment (MCI) may provide opportunities for early diagnosis and intervention. However, the role of retinal vascular biomarkers remains controversial. We aim to perform a systematic review, meta-analysis and meta-regression to evaluate the comprehensive retinal microvasculature changes in patients with AD and MCI. Methods We conducted a literature search on PubMed, MEDLINE, and EMBASE to identify studies published before May 2021 which assessed the measurements of optical coherence tomography angiography (OCTA) between AD, MCI with healthy control eyes, including foveal avascular zone (FAZ), vessel density (VD) of peripapillary, superficial and deep capillary plexus, and choroidal thickness using a random-effect model. We also performed meta-regression and subgroup analysis and assessed heterogeneity and publication bias to evaluate potential sources of bias. Results Compared with control eyes, VD of superficial capillary plexus was significantly lower in AD [standardized mean difference (SMD): −0.48; 95% CI (−0.70 to −0.27); p = 0.04] and MCI eyes [SMD: −0.42; 95% CI (−0.81 to −0.03); p = 0.03], as well as reduced VD of deep capillary plexus [SMD: −1.19; 95% CI (−2.00 to −0.38]; p < 0.001], [SMD: −0.53; 95% CI (−0.85 to −0.22); p < 0.001]. FAZ was significantly enlarged in AD eyes [SMD: 0.54; 95% CI (0.09 to 0.99); p = 0.02]. The meta-regression analysis showed that the OCTA machine type and macular scan size significantly influenced the variation of VD and FAZ between AD and control eyes (p < 0.05). Conclusion Our results highlight the potential of OCTA as a biomarker to detect early microvasculature deficits in AD and MCI. Notably, the macular scan size and different OCTA machine type could explain the heterogeneity observed in literatures. This information might be useful for future longitudinal study design to evaluate the role of OCTA in monitoring disease progression and treatment efficacy.
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Affiliation(s)
- Tsai-Chu Yeh
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chun-Tung Kuo
- Institute of Health Behaviors and Community Sciences, College of Public Health, National Taiwan University, Taipei, Taiwan
- School of Public Health, National Defense Medical Center, Taipei, Taiwan
| | - Yu-Bai Chou
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- *Correspondence: Yu-Bai Chou
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Wiest MRJ, Bajka A, Hamann T, Foa N, Toro M, Barthelmes D, Zweifel S. Differences in Mean Values and Variance in Quantitative Analyses of Foveal OCTA Imaging. Klin Monbl Augenheilkd 2022; 239:513-517. [PMID: 35472795 DOI: 10.1055/a-1766-7268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE Multiple approaches for quantifying parameters such as vessel density (VD) and vessel length density (VLD) in optical coherence tomography angiography (OCTA) en-face segmentations are currently available. While it is common knowledge that data gathered from different methods should not be directly compared to each other, a comparison of the different methods can help to further the understanding of differences between different methods of measurement. Here we compare a common method of semiautomatically quantifying VD and VLD with an automated method supplied by the manufacturer of an OCTA device and report on differences in performance in order to probe for and highlight differences in values gathered by both methods. METHODS OCTA was performed using the swept source PLEX Elite 9000 device, software version 2.0.1.47652 (Carl Zeiss Meditec Inc., Dublin, CA, USA). Scans of 3 mm × 3 mm from healthy volunteers centred on the fovea were acquired by a well-trained certified ophthalmologist. Scans with a signal strength of 8 out of 10 or higher were included. Quantitative parameters of the 3 mm × 3 mm cube scans were automatically generated and segmented into superficial capillary plexus (SCP) and deep capillary plexus (DCP) layers using layer segmentation produced by the instrument software and prototype analysis VD quantification software (Macular Density v.0.7.1, ARI Network Hub, Carl Zeiss Meditec Inc., Dublin, CA, USA) supplied by the manufacturer. An alternative approach of quantitative analysis of VD and VLD was performed manually with ImageJ (National Institutes of Health, Bethesda, Maryland, USA), as previously reported. VD was assessed as the ratio of the retinal area occupied by vessels. VDL was measured as the total length of the skeletonised vessels using 1-pixel centre line extraction of the blood vessels. RESULTS We report differences in standard deviation (SD) in OCTA parameters obtained using different methods. The standard deviation of VD and VLD measurements was statistically significantly different in VD of 3 mm × 3 mm DCP (p = 0.009), VLD of 3 mm × 3 mm SCP (p = 0.000), and VLD of 3 mm × 3 mm DCP (p = 0.021). No statistically significant differences were found in VD of 3 mm × 3 mm SCP (p = 0.128) or VLD of 3 mm × 3 mm SCP (p = 0.107). CONCLUSIONS As expected, we were able to demonstrate significant differences in quantitative OCTA parameters gathered from the same images using different methods of quantification. Values gathered using different methods are not interchangeable. In scientific studies and in situations where long-term follow-up is necessary, the same device and the same method of quantification should be used to maintain retrospective comparability of measurements.
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Affiliation(s)
| | - Anahita Bajka
- Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland.,University of Zurich, Zurich, Switzerland
| | - Timothy Hamann
- Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland.,University of Zurich, Zurich, Switzerland
| | - Nastasia Foa
- Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland
| | - Mario Toro
- Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland
| | - Daniel Barthelmes
- Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland.,University of Zurich, Zurich, Switzerland
| | - Sandrine Zweifel
- Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland.,University of Zurich, Zurich, Switzerland
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1-Year Fixed-Regimen Bevacizumab Treatment in DME-Vascular Network Image Analysis in Optical Coherence Tomography Angiography Study. J Clin Med 2022; 11:jcm11082125. [PMID: 35456217 PMCID: PMC9029661 DOI: 10.3390/jcm11082125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/25/2022] [Accepted: 04/06/2022] [Indexed: 12/05/2022] Open
Abstract
Purpose: To evaluate the effectiveness of intravitreal bevacizumab treatment in patients with diabetic macular edema (DME) by assessing retinal changes using AngioTool software (version 0.6a(02.18.14), National Cancer Institute, Bethesda, Maryland). Methods: A total of 27 eyes in patients with treatment-naïve DME were included in this prospective study. OCT-A images with a scan area of 6 × 6 mm were obtained. The DME patients with a central macular thickness (CMT) of ≥300 µm received nine bevacizumab injections within 12 months. The demographic, systemic, and ocular parameters, including the best-corrected visual acuity (BCVA) and CMT, were assessed. Explant area, vessels area, vessels percentage area, total number of junctions, total vessels length, average vessels length, the total number of endpoints, and mean lacunarity in the superficial capillary plexus (SCP) were calculated by using AngioTool software. Results: Twenty-nine eyes of DME patients were subjected to the final analysis. Bevacizumab treatment reduced CMT from 401.84 ± 84.54 µm to 328.93 ± 87.17 µm and improved BCVA from 65.18 ± 8.21 at baseline to 72.63 ± 7.43 letters among participants of the study. The anti-VEGF therapy showed no statistically significant changes in parameters calculated by AngioTool software in the study group of patients. Conclusion: The fixed-regimen intravitreal bevacizumab therapy was effective in treating DME. AngioTool software is an additional tool that could be used to assess vascular networks. However, the use of OCTA is unlikely to alter DME treatment regimens significantly or to find significant predictors. Perhaps using wide-angle devices or software will give a complete picture of the disease and prove to be more helpful.
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LeTran VH, Burkemper B, O'Fee JR, Souverein EA, Lee JC, Phillips MJ, Dinh-Dang D, Song BJ, Xu BY, Wong BJ, Richter GM. Wedge Defects on Optical Coherence Tomography Angiography of the Peripapillary Retina in Glaucoma: Prevalence and Associated Clinical Factors. J Glaucoma 2022; 31:242-249. [PMID: 35089892 DOI: 10.1097/ijg.0000000000001991] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 01/14/2022] [Indexed: 11/25/2022]
Abstract
PRCIS Among subjects with glaucoma, wedge-shaped defects on optical coherence tomography angiography (OCTA) were associated with disc hemorrhages (DH), paracentral visual field (VF) defects, increased cup-to-disc ratio (CDR), and thinner retinal nerve fiber layer (RNFL). PURPOSE To examine determinants of wedge defects on peripapillary OCTA in glaucoma. MATERIALS AND METHODS A total of 278 eyes of 186 subjects with mild to severe primary open-angle glaucoma underwent 6×6 spectral-domain OCTA imaging of the superficial peripapillary retina from 2016 to 2020 at an academic practice. Wedge defects were defined as focal microvasculature loss that extends outward from the optic nerve in an arcuate, wedge shape. Logistic regression models controlling for intereye correlation identified variables significantly associated with wedge defects. Eyes with profound microvasculature loss in both hemispheres were excluded. Candidate variables included: age, sex, race or ethnicity, diabetes, hypertension, follow-up duration, baseline untreated intraocular pressure, intraocular pressure at time of imaging, DH history, paracentral VF defects, CDR, central corneal thickness, spherical equivalent, VF mean deviation, RNFL thickness, and glaucoma stage. RESULTS Of 278 eyes, 126 (45.3%) had wedge defects in at least 1 hemisphere. In our multivariable logistic regression model, wedge defects were associated with DH history [odds ratio (OR): 3.19, 95% confidence interval (CI): 1.05-9.69, P=0.041], paracentral VF defects [OR: 4.38 (95% CI: 2.11-9.11), P<0.0001], larger CDR [OR: 1.27 (95% CI: 1.03-1.56), P=0.024, per 0.1 increase], and thinner RNFL [OR: 1.71 (95% CI: 1.25-2.34), P=0.0009, per 10 μm decrease]. CONCLUSION DH history and paracentral VF defects were independently associated with wedge defects on OCTA, which was present in 45.3% of primary open-angle glaucoma patients. These findings may provide insight into glaucoma pathogenesis.
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Affiliation(s)
- Vivian H LeTran
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Bruce Burkemper
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - John R O'Fee
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Erik A Souverein
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Jae C Lee
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Mark J Phillips
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | | | - Brian J Song
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Benjamin Y Xu
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Brandon J Wong
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Grace M Richter
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA
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OCT Angiography Fractal Analysis of Choroidal Neovessels Secondary to Central Serous Chorioretinopathy, in a Caucasian Cohort. J Clin Med 2022; 11:jcm11051443. [PMID: 35268534 PMCID: PMC8911390 DOI: 10.3390/jcm11051443] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/27/2022] [Accepted: 03/02/2022] [Indexed: 02/06/2023] Open
Abstract
Central serous chorioretinopathy (CSCR) can be complicated by different types of choroidal neovascularization (CNV). The purpose of this study was to investigate the incidence and quantitative optical coherence tomography angiography (OCT-A) features of CSCR-related CNVs. Methods: This was a retrospective multicenter study including 102 eyes of 102 Caucasian patients with acute or complex CSCR. All patients underwent a comprehensive ophthalmological examination. Quantitative OCT-A parameters, including vascular perfusion density (VPD), fractal dimension (FD), and lacunarity (LAC), were measured in CNV eyes. Results: Forty eyes (39.2%) had acute CSCR, whereas the remaining sixty-two (60.8%) had complex CSCR. CNV was observed in 37 (36.27%) eyes, all of which had the complex form. CNVs were classified as type 1 CNV in 11/37 (29.73%) cases and as polypoidal choroidal vasculopathy (PCV) in the remaining 26/37 (70.27%). Overall, the mean VPD, FD, and LAC of CSCR-related CNVs were 0.52 ± 0.20%, 1.44 ± 0.12, and 2.40 ± 1.1, respectively. No significant difference between type 1 CNV and PCV was found. Conclusion: Complex CSCR is often complicated by type 1 CNV and PCV with similar neovascular architecture and branching complexity, a finding supporting the idea that they might be different stages of the same neovascular process. Future OCT-A fractal analysis-based studies that also include other relevant parameters, such as demographics, presentation, morphology on multimodal imaging, and response to treatment, are necessary before drawing any definitive conclusions.
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Otero-Marquez O, Chui TY, Pinhas A, Castanos Toral MV, Zhou DB, Migacz J, Rosen RB. 3-D OCT angiographic evidence of Anti-VEGF therapeutic effects on retinal capillary hemangioma. Am J Ophthalmol Case Rep 2022; 25:101394. [PMID: 35198818 PMCID: PMC8842027 DOI: 10.1016/j.ajoc.2022.101394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 01/30/2022] [Accepted: 01/31/2022] [Indexed: 12/02/2022] Open
Abstract
Purpose To report the impact of intravitreal anti–vascular endothelial growth factor (VEGF) therapy on a retinal capillary hemangioma (RCH) using clinical OCT angiography (OCT-A) in addition to standard imaging modalities. Observations A 25-year-old male patient with Von Hippel-Lindau (VHL) disease presented with a history of bilateral RCH. No view was present in the right eye. Examination of the left eye revealed six peripheral RCH, the smallest of which was temporal to the macula with active exudation. This RCH was thought to be the source of cystoid macular edema (CME) involving the fovea, and therefore, the source of vision decline. 11 injections of 1.25mg of Bevacizumab EA across 14-month was given. Comparison of the pre- and post-treatment OCT-A at the temporal RCH showed a reduction of CME and regression of RCH. Conclusion Anti-VEGF therapy appeared to stabilize the visual acuity and produce partial regression of RCH. It offers a safe option when visual acuity is threatened. OCT and OCT-A have the ability to document the impact of antiangiogenic therapy on RCH. 3D renderings of OCT-A offer enhanced sensitivity to recognition of structural and functional changes of RCH which may prove useful for monitoring treatment response.
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Affiliation(s)
- Oscar Otero-Marquez
- Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA
| | - Toco Yp Chui
- Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA.,Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Alexander Pinhas
- Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA
| | | | - Davis B Zhou
- Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA.,Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Justin Migacz
- Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA
| | - Richard B Rosen
- Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, NY, USA.,Icahn School of Medicine at Mount Sinai, New York, NY, USA
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Shin JD, Wolf AT, Harris A, Verticchio Vercellin A, Siesky B, Rowe LW, Packles M, Oddone F. Vascular biomarkers from optical coherence tomography angiography and glaucoma: where do we stand in 2021? Acta Ophthalmol 2022; 100:e377-e385. [PMID: 34363322 PMCID: PMC8920047 DOI: 10.1111/aos.14982] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/28/2021] [Accepted: 07/01/2021] [Indexed: 12/16/2022]
Abstract
Biomarkers of ocular blood flow originating from a wide variety of imaging modalities have been associated with glaucoma onset and progression for many decades. Advancements in imaging platforms including optical coherence tomography angiography (OCTA) have provided the ability to quantify vascular changes in glaucoma patients, alongside traditional measures such as retinal nerve fibre layer thickness and optic nerve head structure. Current literature on vascular biomarkers, as measured by OCTA, indicates significant relationships between glaucoma and blood flow and capillary density in the retina and ONH. The data currently available, however, are highly diverse and lack robust longitudinal data on OCTA vascular outcomes and glaucoma progression. Herein we discuss and summarize the relevant current literature on OCTA vascular biomarkers and glaucoma reviewed through March 1, 2021. Associations between OCTA vascular biomarkers and clinical structural and functional glaucoma outcomes as well as differences between glaucoma patients and healthy controls are reviewed and summarized. The available data identify significantly decreased flow density, flow index and vessel density in the ONH, peripapillary vascular layer and macula of glaucoma patients compared with controls. Whole image vessel density is also significantly decreased in glaucoma patients compared with controls, and this outcome has been found to correspond to severity of visual field loss. OCTA vascular biomarkers alongside clinical structural outcomes may aid in assessing overall risk for glaucoma in patients.
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Affiliation(s)
- Joshua D. Shin
- School of Medicine, New York Medical College, Valhalla, NY
| | - Amber T. Wolf
- Icahn School of Medicine at Mount Sinai Hospital, New York, NY
| | - Alon Harris
- Icahn School of Medicine at Mount Sinai Hospital, New York, NY
| | | | - Brent Siesky
- Icahn School of Medicine at Mount Sinai Hospital, New York, NY
| | - Lucas W. Rowe
- Indiana University School of Medicine, Indianapolis, IN
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Role of Anterior Segment-Optical Coherence Tomography Angiography in Acute Ocular Burns. Diagnostics (Basel) 2022; 12:diagnostics12030607. [PMID: 35328160 PMCID: PMC8947509 DOI: 10.3390/diagnostics12030607] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/09/2022] [Accepted: 02/21/2022] [Indexed: 02/01/2023] Open
Abstract
Acute ocular burns have varied manifestations which require prompt diagnosis and management to prevent chronic sequelae. Of these, the detection of limbal ischemia poses a challenge because of the subjective nature of its clinical signs. Anterior segment optical coherence tomography angiography (AS-OCTA) offers an objective method of assessing ischemia in these eyes. This review provides an overview of the technology of AS-OCTA and its applications in acute burns. AS-OCTA generates images by isolating the movement of erythrocytes within blood vessels from sequentially obtained b-scans. Limbal ischemia manifests in these scans as absent vasculature and the extent of ischemia can be quantified using different vessel-related parameters. Of these, the density of vessels is most commonly used and correlates with the severity of the injury. Incorporation of the degree of ischemia in the classification of acute burns has been attempted in animal studies and its extension to human trials may provide an added dimension in determining the final prognosis of these eyes. Thus, AS-OCTA is a promising device that can objectively evaluate limbal ischemia. This will facilitate the identification of patients who will benefit from revascularization therapies and stem cell transplants in acute and chronic ocular burns, respectively.
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Duan J, An J, Li M, Zhang Z, Zhou L, Yin P, Ma J, Shang Q. Topographical Relationship Between Acute Macular Neuroretinopathy and Choroidal Watershed Zone or Patchy Choroidal Filling. Front Med (Lausanne) 2022; 9:762609. [PMID: 35178410 PMCID: PMC8843832 DOI: 10.3389/fmed.2022.762609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 01/10/2022] [Indexed: 11/13/2022] Open
Abstract
PURPOSE To study the topographical relationship between acute macular neuroretinopathy (AMN) lesions and the choroidal watershed zone (CWZ) or patchy choroidal filling (PCF) using multimodal imaging. METHODS Lesions in patients diagnosed with AMN were clinically examined using multimodal imaging, including fundus photography, near-infrared reflectance imaging, spectral-domain optical coherence tomography (OCT), fluorescein angiography, indocyanine green angiography, OCT angiography, and microperimetry. The topographical relationship between AMN and the CWZ or PCF was evaluated. RESULTS Seven eyes of six patients were included in the study. The mean age of the patients was 35.8 ± 11.7 years. The AMN lesions were collocated with the CWZ in five eyes and the PCF in one eye. Among these eyes, three had complete patterns, and three had partial patterns. Only one eye showed no topographical relationship between AMN and the CWZ or PCF. CONCLUSION The colocation of AMN and CWZ/PCF suggests that the AMN lesions were within an area with a dual-watershed zone: the watershed zone between the retinal deep capillary plexus and choriocapillaris, and the choroidal watershed zone or patchy choroidal filling. This retinal area was highly vulnerable to hypoperfusion. Our results suggest a novel pathophysiological mechanism for AMN.
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Affiliation(s)
- Jialiang Duan
- Department of Ophthalmology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Jianbin An
- Department of Ophthalmology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Minhao Li
- Department of Ophthalmology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Zhengwei Zhang
- Department of Ophthalmology, The Affiliated Wuxi No. 2 People's Hospital of Nanjing Medical University, Wuxi, China
| | - Liang Zhou
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, China
| | - Pengfei Yin
- Department of Ophthalmology, The Third Affiliated Hospital of Hebei Medical University, Shijiazhuang, China
| | - Jingxue Ma
- Department of Ophthalmology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Qingli Shang
- Department of Ophthalmology, The Second Hospital of Hebei Medical University, Shijiazhuang, China
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Ulfik-Dembska K, Teper S, Dembski M, Nowińska A, Wylęgała E. Idiopathic Epiretinal Membrane: Microvasculature Analysis with Optical Coherence Tomography and Optical Coherence Tomography Angiography. Tomography 2022; 8:189-199. [PMID: 35076629 PMCID: PMC8788506 DOI: 10.3390/tomography8010016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 01/06/2022] [Indexed: 11/16/2022] Open
Abstract
Background: The present study examined the relationships among macular microvasculature, retinal structure, and epiretinal membrane (ERM) and explored the utility of optical coherence tomography (OCT) angiography (OCTA) in idiopathic ERM assessment. Methods: The study sample comprised 276 eyes of 276 patients. A total of 154 eyes with ERM and 122 normal (control) eyes were analyzed. Only one eye of each participant was randomly selected for posterior segment imaging. Each patient underwent OCT and OCTA. Images were analyzed with AngioTool 0.6. Results: Foveal avascular zone was significantly smaller in the ERM group (p = 0.044). Average retinal thickness and foveal thickness were significantly higher in the ERM group (both p = 0.001). Moreover, 64 (41.5%) patients exhibited no metamorphopsia, while 46 (29.8%) and 44 (28.7%) patients exhibited moderate and extensive metamorphopsias, respectively. Meanwhile, FAZ was negatively correlated with central retinal thickness in the ERM group. The vessel area (p = 0.0017) and vessel percentage area (p = 0.044) were significantly greater in the ERM group. Conclusions: Changes observed in the superficial plexus in OCTA are related to the severity of metamorphopsia and can be further evaluated to support decision making regarding the surgical management of idiopathic ERM.
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Affiliation(s)
- Klaudia Ulfik-Dembska
- Clinical Department of Ophthalmology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Poniatowskiego 15, 40-566 Katowice, Poland; (S.T.); (M.D.); (A.N.); (E.W.)
- District Railway Hospital, Panewnicka 65, 40-760 Katowice, Poland
- Correspondence: ; Tel.: +48-32-605-35-92
| | - Sławomir Teper
- Clinical Department of Ophthalmology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Poniatowskiego 15, 40-566 Katowice, Poland; (S.T.); (M.D.); (A.N.); (E.W.)
- District Railway Hospital, Panewnicka 65, 40-760 Katowice, Poland
| | - Michał Dembski
- Clinical Department of Ophthalmology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Poniatowskiego 15, 40-566 Katowice, Poland; (S.T.); (M.D.); (A.N.); (E.W.)
- District Railway Hospital, Panewnicka 65, 40-760 Katowice, Poland
| | - Anna Nowińska
- Clinical Department of Ophthalmology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Poniatowskiego 15, 40-566 Katowice, Poland; (S.T.); (M.D.); (A.N.); (E.W.)
- District Railway Hospital, Panewnicka 65, 40-760 Katowice, Poland
| | - Edward Wylęgała
- Clinical Department of Ophthalmology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, Poniatowskiego 15, 40-566 Katowice, Poland; (S.T.); (M.D.); (A.N.); (E.W.)
- District Railway Hospital, Panewnicka 65, 40-760 Katowice, Poland
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Roberts PK, Schranz M, Motschi A, Desissaire S, Hacker V, Pircher M, Sacu S, Buehl W, Hitzenberger CK, Schmidt-Erfurth UM. Baseline predictors for subretinal fibrosis in neovascular age-related macular degeneration. Sci Rep 2022; 12:88. [PMID: 34996934 PMCID: PMC8741927 DOI: 10.1038/s41598-021-03716-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 12/07/2021] [Indexed: 11/20/2022] Open
Abstract
To find baseline predictors for subretinal fibrosis (SF) in neovascular age-related macular degeneration (nAMD). Forty-five eyes of 45 participants with treatment-naïve nAMD were consecutively enrolled and treated according to a standardized treat-and-extend protocol. Spectral-domain optical coherence tomography (OCT), color fundus photography and fluorescein angiography as well as novel imaging modalities polarization-sensitive OCT and OCT angiography (OCTA) were performed to detect SF after 1 year and find baseline predictors for SF development. Baseline OCTA scans were evaluated for quantitative features such as lesion area, vessel area, vessel junctions, vessel length, vessel endpoints and mean lacunarity. Additionally, the type of macular neovascularization, the presence of subretinal fluid, intraretinal fluid (IRF), subretinal hyperreflective material (SHRM), retinal hemorrhage as well as best-corrected visual acuity (BCVA) were evaluated. After 12 months 8 eyes (18%) developed SF. Eyes with SF had worse baseline BCVA (p = .001) and a higher prevalence of IRF (p = .014) and SHRM at baseline (p = .017). There was no significant difference in any of the evaluated quantitative OCTA parameters (p > .05) between eyes with and without SF. There were no quantitative baseline microvascular predictors for SF in our study. Low baseline BCVA, the presence of IRF and SHRM, however, are easily identifiable baseline parameters indicating increased risk.
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Affiliation(s)
- Philipp K Roberts
- Department of Ophthalmology and Optometry, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Markus Schranz
- Department of Ophthalmology and Optometry, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Alice Motschi
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Sylvia Desissaire
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Valentin Hacker
- Department of Ophthalmology and Optometry, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Stefan Sacu
- Department of Ophthalmology and Optometry, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Wolf Buehl
- Department of Ophthalmology and Optometry, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Christoph K Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Ursula M Schmidt-Erfurth
- Department of Ophthalmology and Optometry, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
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Ripolles-Garcia A, Ruthel G, Ying GS, Chen Y, Cuenca N, Aguirre GD, Beltran WA. Characterization of the Canine Retinal Vasculature With Optical Coherence Tomography Angiography: Comparisons With Histology and Fluorescein Angiography. Front Neuroanat 2021; 15:785249. [PMID: 34966262 PMCID: PMC8710516 DOI: 10.3389/fnana.2021.785249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 11/23/2021] [Indexed: 11/16/2022] Open
Abstract
Purpose: To present a methodology for quantification of the canine retinal vasculature imaged by optical coherence tomography angiography (OCTA) and validate this approach by comparison with fluorescein angiography (FA) and confocal imaging of retinal wholemounts labelled by immunohistochemistry (IHC). Methods: Six normal adult dogs underwent retinal OCTA imaging in both eyes. The images extracted from the different microvascular plexuses at eight retinal locations spanning the central and mid-peripheral fundus were analyzed using the AngioTool software. FA was performed in one eye and was compared to the OCTA images. Six eyes from three dogs were processed by IHC to examine the retinal vasculature. Results: A total of four retinal plexuses were identified by OCTA in the canine retina, and their density and topographical pattern varied with eccentricity. OCTA offered improved resolution over FA with the advantage of allowing imaging of the individual plexuses. Detection by OCTA of small vessels within the deep capillary plexus was possible and approached the level of resolution achieved with ex vivo imaging of the retinal vasculature by confocal microscopy/IHC. The plexuses herein described are analogous to human retinal vasculature. Conclusion: OCTA can be used to image and quantify non-invasively the vascular retinal networks of the canine retina. We provide normative data in eight different retinal locations that can be imaged non-invasively with this technology. This could support analysis of retinal vascular changes associated with disease and following therapeutic intervention.
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Affiliation(s)
- Ana Ripolles-Garcia
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Gordon Ruthel
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Gui-Shuang Ying
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Yineng Chen
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Nicolas Cuenca
- Department of Physiology, Genetics and Microbiology, University of Alicante, Alicante, Spain
| | - Gustavo D. Aguirre
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - William A. Beltran
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Roberts PK, Schranz M, Motschi A, Desissaire S, Hacker V, Pircher M, Sacu S, Buehl W, Hitzenberger CK, Schmidt-Erfurth U. Morphologic and Microvascular Differences Between Macular Neovascularization With and Without Subretinal Fibrosis. Transl Vis Sci Technol 2021; 10:1. [PMID: 34851359 PMCID: PMC8648059 DOI: 10.1167/tvst.10.14.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Purpose To evaluate morphologic and microvascular differences between eyes with and without subretinal fibrosis (SF) caused by neovascular age-related macular degeneration (nAMD). Methods Patients with nAMD with a minimum history of 12 months of anti-VEGF treatment were prospectively included in this cross-sectional study. Patients were imaged using standard imaging, swept-source optical coherence tomography angiography for quantitative microvascular analysis and polarization-sensitive OCT as an ancillary method for automated SF segmentation. The presence of reticular pseudodrusen, hyperreflective foci (HRF), and outer retinal tubulation (ORT) were also evaluated. Results Sixty eyes of 60 participants (37 female) with nAMD and a mean 3.1 (±2.7)-year history of anti-VEGF treatment were included, 20 (33%) of which were diagnosed with SF. Eyes with SF had a higher prevalence of ORT (P < 0.001) and a lower prevalence of HRF (P = 0.004) than eyes without SF. Fifty eyes were analyzed quantitatively for microvascular biomarkers. Eyes with SF had a larger greatest vascular caliber (P = 0.001) and greatest linear diameter (P = 0.042), a larger microvascular neovascularization (MNV) area (P = 0.026), larger vessel area (P = 0.037), higher number of vessel junctions (P = 0.025), longer total vessel length (P = 0.027), higher number of vessel endpoints (P = 0.007), and higher endpoint density (P = 0.047). Conclusions This multimodal imaging approach demonstrated in vivo microvascular and morphological differences in eyes with and without SF. Eyes with SF tend to have larger MNV lesions with thicker vessels and are often associated with the presence of ORT. Translational Relevance This study points out imaging biomarkers in patients with SF, which may help identifying high-risk patients.
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Affiliation(s)
- Philipp Ken Roberts
- Department of Ophthalmology and Optometry of the Medical University of Vienna, Vienna, Austria
| | - Markus Schranz
- Department of Ophthalmology and Optometry of the Medical University of Vienna, Vienna, Austria
| | - Alice Motschi
- Center for Medical Physics and Biomedical Engineering of the Medical University of Vienna, Vienna, Austria
| | - Sylvia Desissaire
- Center for Medical Physics and Biomedical Engineering of the Medical University of Vienna, Vienna, Austria
| | - Valentin Hacker
- Department of Ophthalmology and Optometry of the Medical University of Vienna, Vienna, Austria
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering of the Medical University of Vienna, Vienna, Austria
| | - Stefan Sacu
- Department of Ophthalmology and Optometry of the Medical University of Vienna, Vienna, Austria
| | - Wolf Buehl
- Department of Ophthalmology and Optometry of the Medical University of Vienna, Vienna, Austria
| | | | - Ursula Schmidt-Erfurth
- Department of Ophthalmology and Optometry of the Medical University of Vienna, Vienna, Austria
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Khatri A, Pandey A, Joshi K, Singh K, Prasai G, Pradhan E, Agrawal R. Redefining response in wet AMD to anti VEGF therapy based on non-OCTA versus OCTA evaluation. Eur J Ophthalmol 2021; 32:2719-2725. [PMID: 34796729 DOI: 10.1177/11206721211059349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Anti vascular endothelial growth factor (anti VEGF) has been the mainstay of treatment in wet age-related macular degeneration (AMD). Subsequent decision to continue anti VEGF therapy depends on the treatment response quantified by functional (visual acuity) and morphological (optical coherence tomography) parameters then categorized from good to poor. METHODS This study evaluates the agreement between OCT angiography (OCTA) and non-OCTA (logMAR VA plus OCT) to decide anti-VEGF treatment's continuity. After an anti VEGF treatment, on a follow up visit, a patient underwent non-OCTA evaluation (decision A) then OCTA evaluation (decision B) to judge the necessity of future anti VEGF application. RESULTS Out of 129 eyes, on 72 eyes (49%), there were agreements on both decision arms, but on 55 eyes (42%) there was disagreement. Particularly, disagreement on 47/55 eyes was important, where OCTA advised "continue anti VEGF" and non-OCTA advised "Stop anti VEGF" therapy. Cohen's Kappa for probability of agreement to continue anti VEGF was fair (0.33) and to stop anti VEGF therapy was none (0.1). CONCLUSIONS Based on resulting disagreements between the two modalities on deciding the continuity of anti VEGF, we conclude that OCTA must be considered in the conventional decision making algorithm in patients with wet AMD under anti VEGF therapy.
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Affiliation(s)
- Anadi Khatri
- Birat Eye Hospital, Biratnagar, Nepal.,475231Birat Medical College and Teaching Hospital, Biratnagar, Nepal
| | | | - Kriti Joshi
- 128584Lumbini Eye Institute and Research Centre, Siddharthanagar, Nepal
| | | | - Gunjan Prasai
- 128550Kathmandu Medical College and Teaching Hospital, Kathmandu, Nepal
| | - Eli Pradhan
- 97985Tilganga Institute of Ophthalmology, Kathmandu, Nepal
| | - Rupesh Agrawal
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National, University of Singapore, Singapore.,Ophthalmology Academic Clinical Program, Duke-NUS Graduate Medical School, Singapore.,National Healthcare Group Eye Institute, 63703Tan Tock Seng Hospital, Singapore.,Lee Kong Chian School of Medicine, Singapore
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