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Guldfeldt MU, Pilegaard FP, Malmqvist L, Klefter ON, Hamann S. Validation of retinal oximetry vessel selection using fluorescein angiography in patients with optic disc drusen. Exp Eye Res 2024; 243:109882. [PMID: 38582182 DOI: 10.1016/j.exer.2024.109882] [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: 11/22/2023] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/08/2024]
Abstract
Retinal oximetry could provide insights into the pathophysiology of optic nerve disease, including optic disc drusen (ODD). Vessel selection for oximetry analysis is based on morphological characteristics of arterioles and venules and supported by an overlay of estimated blood oxygen saturations. The purpose of this cross-sectional study was to determine the validity of this vessel selection procedure by comparing it with vessel selection supported by video fluorescein angiography (FA). The study included 36 eyes of 36 patients with ODD who underwent retinal oximetry (Oxymap retinal oximeter T1) followed by FA (Heidelberg Spectralis). Two trained graders selected vessel segments in a pre-defined measurement area around the optic disc. One of these graders additionally performed the vessel segment selection with the support of FA images. When performed by the same grader, FA-supported and non-FA-supported vessel selection did not lead to significant differences in total vessel segment length, estimated oxygen saturations or vessel diameters (all p > 0.05). Inter-grader differences were found for arterial and venous segment lengths and arterial saturation (p < 0.05). A similar tendency was found for the arteriovenous saturation difference (p = 0.10). In conclusion, identifying vessel segments for retinal oximetry analysis based on vessel morphology and supported by a color-coded saturation overlay appears to be a valid method without the need for invasive angiography. A numerically small inter-grader variation may influence oximetry results. Further studies of retinal oximetry in ODD are warranted.
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Affiliation(s)
- Mia Uhre Guldfeldt
- Department of Ophthalmology, Rigshospitalet, Copenhagen, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Freja Pind Pilegaard
- Department of Ophthalmology, Rigshospitalet, Copenhagen, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Lasse Malmqvist
- Department of Ophthalmology, Rigshospitalet, Copenhagen, Denmark
| | - Oliver Niels Klefter
- Department of Ophthalmology, Rigshospitalet, Copenhagen, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Steffen Hamann
- Department of Ophthalmology, Rigshospitalet, Copenhagen, Denmark; Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
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2
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Beach JM, Shoemaker B, Eckert GJ, Harris A, Siesky B, Arciero JC. Potential measurement error from vessel reflex and multiple light paths in dual-wavelength retinal oximetry. Acta Ophthalmol 2024; 102:e367-e380. [PMID: 37786359 PMCID: PMC10987395 DOI: 10.1111/aos.15776] [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: 01/11/2023] [Revised: 08/15/2023] [Accepted: 09/18/2023] [Indexed: 10/04/2023]
Abstract
PURPOSE This study aims to characterize the dependence of measured retinal arterial and venous saturation on vessel diameter and central reflex in retinal oximetry, with an ultimate goal of identifying potential causes and suggesting approaches to improve measurement accuracy. METHODS In 10 subjects, oxygen saturation, vessel diameter and optical density are obtained using Oxymap Analyzer software without diameter correction. Diameter dependence of saturation is characterized using linear regression between measured values of saturation and diameter. Occurrences of negative values of vessel optical densities (ODs) associated with central vessel reflex are acquired from Oxymap Analyzer. A conceptual model is used to calculate the ratio of optical densities (ODRs) according to retinal reflectance properties and single and double-pass light transmission across fixed path lengths. Model-predicted values are compared with measured oximetry values at different vessel diameters. RESULTS Venous saturation shows an inverse relationship with vessel diameter (D) across subjects, with a mean slope of -0.180 (SE = 0.022) %/μm (20 < D < 180 μm) and a more rapid saturation increase at small vessel diameters reaching to over 80%. Arterial saturation yields smaller positive and negative slopes in individual subjects, with an average of -0.007 (SE = 0.021) %/μm (20 < D < 200 μm) across all subjects. Measurements where vessel brightness exceeds that of the retinal background result in negative values of optical density, causing an artifactual increase in saturation. Optimization of model reflectance values produces a good fit of the conceptual model to measured ODRs. CONCLUSION Measurement artefacts in retinal oximetry are caused by strong central vessel reflections, and apparent diameter sensitivity may result from single and double-pass transmission in vessels. Improvement in correction for vessel diameter is indicated for arteries however further study is necessary for venous corrections.
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Affiliation(s)
| | - Benjamin Shoemaker
- Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana, USA
| | - George J Eckert
- Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Alon Harris
- Icahn School of Medicine, Mt. Sinai, New York, USA
| | - Brent Siesky
- Icahn School of Medicine, Mt. Sinai, New York, USA
| | - Julia C Arciero
- Indiana University - Purdue University Indianapolis (IUPUI), Indianapolis, Indiana, USA
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3
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Morin H, Havlík J, Chrapek O, Hrevuš M, Nemec P, Rejmont L, Tesar J, Kalousova M, Zima T, Šín M. Correlation Between Vitreous Level of Angiogenic Growth Factors and Oxygen Saturation in Retinal Vessels in Diabetic Retinopathy. Invest Ophthalmol Vis Sci 2023; 64:4. [PMID: 38047739 DOI: 10.1167/iovs.64.15.4] [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: 12/05/2023] Open
Abstract
Purpose The aim of this study was to investigate whether there is any association between the levels of the angiogenic growth factors and the vascular oxygen saturation in eyes with diabetic retinopathy. Methods The study was designed as a prospective trial. The cohort consisted of 29 diabetic patients with scheduled vitreous procedures (intravitreal injection or pars plana vitrectomy). The control group included 30 patients scheduled for macular surgery (macular hole or epiretinal membrane). Nine patients (four from the diabetic maculopathy [DM] group and five from the control group) were excluded from the study because of unsuccessful vitreous samples. Retinal oximetry was performed several hours before the vitreous procedure was performed, and vitreous samples were obtained during the procedure. The concentrations of VEGF, Serpin F1/pigment epithelium-derived factor (PEDF), and placental growth factor (PlGF) were measured by ELISA. Results A negative correlation between level of VEGF and arteriovenous (AV) saturation difference was determined in the DM group (Pearson correlation coefficient r = -0.607; two-tailed test, P = 0.002). Also a negative correlation between level of PlGF and AV saturation difference was determined in the DM group (Pearson correlation coefficient r = -0.521; two-tailed test, P = 0.011) A positive correlation between PlGF level and the vein saturation was not statistically significant (Pearson correlation coefficient r = 0.325; two-tailed test, P = 0.130). We did not find any correlation between vitreous level of PEDF and vascular saturation within the DM group. Conclusions Our findings in diabetic patients suggests a correlation between the intravitreal level of proangiogenic factors and the AV difference measured by retinal oximetry.
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Affiliation(s)
- Hana Morin
- Department of Ophthalmology, Military University Hospital Prague, 1 st Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Jan Havlík
- Department of Ophthalmology, Military University Hospital Prague, 1 st Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Oldrich Chrapek
- Department of Ophthalmology, Faculty of Medicine, Masaryk University Brno, Czech Republic
- Department of Ophthalmology, University Hospital, Brno, Czech Republic
| | - Michal Hrevuš
- Department of Ophthalmology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Pavel Nemec
- Department of Ophthalmology, Military University Hospital Prague, 1 st Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Leoš Rejmont
- Department of Ophthalmology, Military University Hospital Prague, 1 st Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Jan Tesar
- Department of Ophthalmology, Military University Hospital Prague, 1 st Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Marta Kalousova
- Institute of Medical Biochemistry and Laboratory Diagnostics, First Faculty of Medicine, Charles University, and General University Hospital in Prague, Prague, Czech Republic
| | - Tomaš Zima
- Institute of Medical Biochemistry and Laboratory Diagnostics, First Faculty of Medicine, Charles University, and General University Hospital in Prague, Prague, Czech Republic
| | - Martin Šín
- Department of Ophthalmology, Military University Hospital Prague, 1 st Faculty of Medicine, Charles University, Prague, Czech Republic
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4
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Drachmann J, Jeppesen SK, Bek T. Increased Oxygen Saturation in Retinal Venules During Isometric Exercise Is Accompanied With Increased Peripheral Blood Flow in Normal Persons. Invest Ophthalmol Vis Sci 2023; 64:25. [PMID: 37847224 PMCID: PMC10593131 DOI: 10.1167/iovs.64.13.25] [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: 06/29/2023] [Accepted: 09/29/2023] [Indexed: 10/18/2023] Open
Abstract
Purpose A recent study has shown that an increase in the arterial blood pressure of approximately 10 mm Hg in healthy persons can increase the oxygen saturation in venules from the retinal periphery but not from the macular area. The purpose of the present study was to investigate whether a higher increase in blood pressure has further effects on oxygen saturations and whether this is accompanied with changes in retinal blood flow. Methods In 30 healthy persons, oxygen saturation, diameter, and blood flow were measured in arterioles to and venules from the retinal periphery and the macular area. The experiments were performed before and during an experimental increase in arterial blood pressure of (mean ± SD) 18.3 ± 6.2 mm Hg. Results A higher number of venules than arterioles branching from the temporal vascular arcades to the macular area was balanced by a smaller diameter of the venules. Isometric exercise induced significant contraction of both peripheral and macular arterioles (P < 0.01 for both comparisons) and significant increase in oxygen saturation in both peripheral and macular venules (P < 0.001 for both comparisons). This was accompanied with a significant increase in the blood flow in the peripheral arterioles and venules (P = 0.4 for both comparisons), but not in their macular counterparts (P > 0.06 for both comparisons). Conclusions Increased systemic blood pressure leading to arterial contraction and increased venous oxygen saturation in the retina in normal persons can increase peripheral blood flow without significant effects on macular blood flow. This may contribute to explaining regional differences in the response pattern of retinal vascular disease.
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Affiliation(s)
- Jacob Drachmann
- Department of Ophthalmology, Aarhus University Hospital, Aarhus N, Aarhus, Denmark
| | | | - Toke Bek
- Department of Ophthalmology, Aarhus University Hospital, Aarhus N, Aarhus, Denmark
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Frederiksen KH, Pedersen FN, Vergmann AS, Yang D, Laugesen CS, Vestergaard JP, Sørensen TL, Cheung CY, Kawasaki R, Peto T, Grauslund J. Predictive value of retinal oximetry, optical coherence tomography angiography and microperimetry in patients with treatment-naïve branch retinal vein occlusion. Int J Retina Vitreous 2023; 9:38. [PMID: 37381014 DOI: 10.1186/s40942-023-00468-7] [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: 03/17/2023] [Accepted: 04/06/2023] [Indexed: 06/30/2023] Open
Abstract
Vascular endothelial growth factor inhibitors have substantially improved the visual outcomes in patients with macular edema (ME) caused by branch retinal vein occlusion (BRVO), but treatment outcomes are highly variable and early prediction of expected clinical outcome would be important for individualized treatment.As non-invasive metabolic, structural and functional retinal markers might act as early predictors of clinical outcomes, we performed a 12-month, prospective study aimed to evaluate if baseline retinal oximetry, optical coherence tomography angiography (OCT-A) or microperimetry were able to predict need of treatment, structural or functional outcome in patients with ME caused by treatment-näive BRVO.We evaluated 41 eyes of 41 patients with a mean age of 69.6 years and 56% females. We found a strong tendency towards a higher retinal arteriolar oxygen saturation in patients without a need of additional aflibercept treatment after the loading phase (99.8% vs. 92.3%, adjusted odds ratio 0.80 (95% confidence interval 0.64-1.00), adjusted p = 0.058), but otherwise, retinal oximetry, OCT-A or microperimetry were not able to predict need of treatment, structural nor functional outcomes. (Trial registration: clinicaltrials.gov, S-20,170,084. Registered 24 August 2014, https://clinicaltrials.gov/ct2/show/NCT03651011 ).
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Affiliation(s)
- Katrine Hartmund Frederiksen
- Department of Ophthalmology, Odense University Hospital, Odense, Denmark.
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
| | - Frederik Nørregaard Pedersen
- Department of Ophthalmology, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | | | - Dawei Yang
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China
| | | | | | - Torben Lykke Sørensen
- Department of Ophthalmology, Zealand University Hospital, Roskilde, Denmark
- Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, Denmark
| | - Carol Y Cheung
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, Hong Kong, China
| | - Ryo Kawasaki
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- Department of Vision Informatics, Osaka University School of Medicine, Osaka, Japan
| | - Tunde Peto
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University, Belfast, Northern Ireland, UK
| | - Jakob Grauslund
- Department of Ophthalmology, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
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6
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Turnbull CD, Stradling JR, Heitmar R. The effect of obstructive sleep apnea on retinal arterial and venous oxygen saturations: further evidence from a randomised study. Graefes Arch Clin Exp Ophthalmol 2023; 261:1757-1759. [PMID: 36640184 DOI: 10.1007/s00417-023-05973-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 11/28/2022] [Accepted: 01/04/2023] [Indexed: 01/15/2023] Open
Affiliation(s)
- Chris D Turnbull
- Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Department of Respiratory Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.
- Oxford NIHR Biomedical Research Centre, University of Oxford, Oxford, UK.
| | - John R Stradling
- Oxford NIHR Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Rebekka Heitmar
- Centre for Vision Across the Lifespan (CVLS), School of Applied Sciences, University of Huddersfield, Huddersfield, UK.
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7
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Zhang J, Luo Z, Wang G, Huang Y, Fei K, Liu Y, Li J, Yuan J, Xiao P. Oxygen-saturation-related functional parameter as a biomarker for diabetes mellitus-extraction method and clinical validation. Front Cell Dev Biol 2023; 11:1195873. [PMID: 37250897 PMCID: PMC10213938 DOI: 10.3389/fcell.2023.1195873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/02/2023] [Indexed: 05/31/2023] Open
Abstract
Purpose: To develop a computational method for oxygen-saturation-related functional parameter analysis of retinal vessels based on traditional color fundus photography, and to explore their characteristic alterations in type 2 diabetes mellitus (DM). Methods: 50 type 2 DM patients with no-clinically detectable retinopathy (NDR) and 50 healthy subjects were enrolled in the study. An optical density ratio (ODR) extraction algorithm based on the separation of oxygen-sensitive and oxygen-insensitive channels in color fundus photography was proposed. With precise vascular network segmentation and arteriovenous labeling, ODRs were acquired from different vascular subgroups, and the global ODR variability (ODRv) was calculated. Student's t-test was used to analyze the differences of the functional parameters between groups, and regression analysis and receiver operating characteristic (ROC) curves were used to explore the discrimination efficiency of DM patients from healthy subjects based on these functional parameters. Results: There was no significant difference in the baseline characteristics between the NDR and healthy normal groups. The ODRs of all vascular subgroups except the micro venule were significantly higher (p<0.05, respectively) while ODRv was significantly lower (p<0.001) in NDR group than that in healthy normal group. In the regression analysis, the increased ODRs except micro venule and decreased ODRv were significantly correlated with the incidence of DM, and the C-statistic for discrimination DM with all ODR is 0.777 (95% CI 0.687-0.867, p<0.001). Conclusion: A computational method to extract the retinal vascular oxygen-saturation-related optical density ratios (ODRs) with single color fundus photography was developed, and increased ODRs and decreased ODRv of retinal vessels could be new potential image biomarkers of DM.
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Affiliation(s)
| | | | | | | | | | | | | | - Jin Yuan
- *Correspondence: Jin Yuan, ; Peng Xiao,
| | - Peng Xiao
- *Correspondence: Jin Yuan, ; Peng Xiao,
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8
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Ge S, Yang L, Zhou Y, Li C, Zhang J. Retinal Vascular Oxygen Saturation in Adults With Anisometropia. Transl Vis Sci Technol 2023; 12:14. [PMID: 37052910 PMCID: PMC10103718 DOI: 10.1167/tvst.12.4.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023] Open
Abstract
Purpose This study aimed to examine the differences of retinal oxygen saturation between the paired eyes in anisometropia and to further explore the relation between retinal oxygenation and myopia. Methods This was an observational cross-sectional study, with 124 adults with anisometropia included. According to the interocular differences in spherical equivalent (SE), individuals with a difference ≥3.0 D belonged to the ΔSE ≥ 3.0 D group, and those with a difference ≥1.5 D and <3.0 D belonged to the ΔSE <3.0 D group. The ΔSE ≥ 3.0 D group contained 61, and the ΔSE < 3.0 D group contained 64. All were performed examinations of retinal oximetry, SE, axial length (AL), intraocular pressure, central corneal thickness and average keratometry. Results The median SE and AL were -5.06 (-7.22 ∼ -3.41) D and 25.54 (24.73 ∼ 26.62) mm in the "ΔSE < 3 D" group and -4.25 (-6.88 ∼ -2.09) D and 25.52 (24.49 ∼ 26.45) mm in the other group. The retinal arterial oxygen saturation (SaO2) was 93.97% ± 1.26% in the less myopic eyes and 93.18% ± 1.53% (P < 0.001) in the more myopic eyes. In multivariate analyses, SE and AL were both significantly associated with the SaO2. Conclusions The SaO2 between anisometropic myopic eyes was different, and it was associated with SE and AL. Translational Relevance This study demonstrates a relationship between myopia and retinal vascular oxygenation through a novel retinal oximeter.
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Affiliation(s)
- Shanshan Ge
- Eye School of Chengdu University of TCM, Chengdu, Sichuan, China
- Beijing Ming Vision and Ophthalmology, Beijing, China
| | - Liang Yang
- Bright Eye Hospital in Harbin, Harbin, Heilongjiang, China
| | - Yuehua Zhou
- Eye School of Chengdu University of TCM, Chengdu, Sichuan, China
- Beijing Ming Vision and Ophthalmology, Beijing, China
| | - Chen Li
- Beijing Ming Vision and Ophthalmology, Beijing, China
| | - Jing Zhang
- Beijing Ming Vision and Ophthalmology, Beijing, China
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Hübnerová P, Karhanová M, Krhovská P, Minařík J, Mlčák P, Pašková B, Schreiberová Z, Šínová I, Zapletalová J, Šín M. Retinal oxygen saturation in monoclonal gammopathies patients: A pilot study. Acta Ophthalmol 2023; 101:e143-e153. [PMID: 36004612 DOI: 10.1111/aos.15239] [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: 12/18/2021] [Revised: 07/06/2022] [Accepted: 08/14/2022] [Indexed: 11/29/2022]
Abstract
PURPOSE The aim of this pilot study was to assess oxygen saturation in retinal blood vessels in patients with monoclonal gammopathies (MGs). METHODS Thirty-one patients with MGs (11 women and 20 men, mean age 65.9 ± 8.9 years) were enrolled during 2016-2020. The patients were diagnosed at the Haemato-Oncology Department and subsequently examined at the Ophthalmology Department before initiating systemic therapy. All patients were subjected to automatic retinal oximetry (Oxymap ehf.) and had their fundus photographed (Topcon TRC-50DX retinal camera). We assessed the association between retinal oxygen saturation (SatO2 ) - arterial SatO2 , venous SatO2 and arterio-venous (AV) difference-and MGs parameters: serum monoclonal immunoglobulin (M-protein) level and serum immunoglobulin-free light chains (FLC kappa and lambda), total protein, serum viscosity, haemoglobin, albumin, lactate dehydrogenase, C-reactive protein, creatinine and serum calcium level. Hyperviscosity-related retinopathy was also evaluated. RESULTS Statistical analysis showed a significant positive correlation (r = 0.462; p = 0.009) between the AV difference and the haemoglobin level. A significant, medium strong negative correlation was found between the AV difference and the serum levels of the monoclonal light lambda chains (r = -0.450; p = 0.011). Contrary to expectations, no statistically significant correlation was found between retinal oxygen saturation and the total protein or viscosity. CONCLUSION This study found correlation between retinal oxygen saturation and certain parameters in the blood of patients with MGs. Increasing levels of monoclonal immunoglobulin seem to reduce oxygen absorption in retinal arterioles, resulting in a lower AV difference, particularly in patients with a high free light chain level.
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Affiliation(s)
- Petra Hübnerová
- Department of Ophthalmology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic.,Department of Physiology, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Marta Karhanová
- Department of Ophthalmology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Petra Krhovská
- Department of Haemato-oncology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Jiří Minařík
- Department of Haemato-oncology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Petr Mlčák
- Department of Ophthalmology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic.,Department of Physiology, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Barbora Pašková
- Department of Ophthalmology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic.,Department of Physiology, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Zuzana Schreiberová
- Department of Ophthalmology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Irena Šínová
- Department of Ophthalmology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Jana Zapletalová
- Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic
| | - Martin Šín
- Department of Ophthalmology, University Hospital Olomouc, Faculty of Medicine and Dentistry, Palacký University Olomouc, Olomouc, Czech Republic.,Department of Ophthalmology, 1st Faculty of Medicine, Military University Hospital Prague, Charles University, Prague, Czech Republic
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10
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Veiby NC, Simeunovic A, Heier M, Brunborg C, Saddique N, Moe MC, Dahl‐Jørgensen K, Petrovski G, Margeirsdottir HD. Retinal venular oxygen saturation is associated with non-proliferative diabetic retinopathy in young patients with type 1 diabetes. Acta Ophthalmol 2022; 100:388-394. [PMID: 34668632 DOI: 10.1111/aos.15018] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/22/2021] [Accepted: 08/31/2021] [Indexed: 11/27/2022]
Abstract
PURPOSE To determine the contribution of retinal vessel density (VD), central retinal vessel diameter and retinal oxygen (O2 ) saturation independently of other known risk factors in the development of non-proliferative diabetic retinopathy (NPDR). METHODS Macular optical coherence tomography angiography (OCTA), central retinal artery/vein equivalent diameter (CRAE/CRVE) measurements and retinal oximetry were performed in a cross-sectional study of 166 eyes from 166 individuals with type 1 diabetes (T1D) aged 14-30 years. Multiple logistic regression analysis was used to investigate whether O2 saturation, retinal vessel diameters and vessel density in the deep capillary plexus (VD-DCP) were associated with NPDR, when adjusting for known risk factors. The individuals were allocated to one group without and one group with NPDR. RESULTS Multiple logistic regression analysis showed that age (OR = 1.25, 95% CI: 1.04-1.49) and AV-difference in O2 saturation (OR = 0.85, 95% CI 0.77-0.93) were significantly associated with NPDR. CONCLUSION Our findings suggest that age and lower AV-O2 saturation difference contribute to explaining the grade of NPDR independently of other well-known risk factors. Reduced delivery of O2 to the retinal tissue is associated with the development of NPDR in young patients with T1D and should be given appropriate weight in the risk stratification at early stages of the disease.
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Affiliation(s)
- Nina C.B.B. Veiby
- Center for Eye Research Department of Ophthalmology Oslo University Hospital Oslo Norway
| | - Aida Simeunovic
- Department of Paediatrics and adolescent Medicine Akershus University Hospital Lorenskog Norway
- Department of Paediatrics Oslo University Hospital Oslo Norway
- Institute of Clinical Medicine Faculty of Medicine University of Oslo Oslo Norway
- Oslo Diabetes Research Centre Oslo Norway
| | - Martin Heier
- Department of Paediatrics Oslo University Hospital Oslo Norway
- Oslo Diabetes Research Centre Oslo Norway
| | - Cathrine Brunborg
- Oslo Centre of Biostatistics and Epidemiology Oslo University Hospital Oslo Norway
| | - Naila Saddique
- Center for Eye Research Department of Ophthalmology Oslo University Hospital Oslo Norway
| | - Morten C. Moe
- Center for Eye Research Department of Ophthalmology Oslo University Hospital Oslo Norway
- Institute of Clinical Medicine Faculty of Medicine University of Oslo Oslo Norway
| | - Knut Dahl‐Jørgensen
- Department of Paediatrics Oslo University Hospital Oslo Norway
- Institute of Clinical Medicine Faculty of Medicine University of Oslo Oslo Norway
- Oslo Diabetes Research Centre Oslo Norway
| | - Goran Petrovski
- Center for Eye Research Department of Ophthalmology Oslo University Hospital Oslo Norway
- Institute of Clinical Medicine Faculty of Medicine University of Oslo Oslo Norway
| | - Hanna D. Margeirsdottir
- Department of Paediatrics Oslo University Hospital Oslo Norway
- Oslo Diabetes Research Centre Oslo Norway
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11
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Jeppesen SK, Bek T. Lack of predictive value of retinal oxygen saturation for visual outcome after angiostatic treatment of branch retinal vein occlusion. Acta Ophthalmol 2022; 100:e737-e742. [PMID: 34318599 DOI: 10.1111/aos.14988] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 07/09/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE Previous studies have shown that the retinal oxygen saturation in central retinal vein occlusion treated with anti-VEGF compound has no predictive value for visual outcome after 12 months. It is of interest to evaluate whether this conclusion is similar for patients with branch retinal vein occlusion among whom only some patients are treated. METHODS Retinal oxygen saturation, visual acuity and central retinal thickness were studied at the time of referral and after six and 12 months in 111 patients successively referred to the Department of Ophthalmology, Aarhus University Hospital, with a venous occlusion affecting branches peripheral from the central retinal venule. The predictive value of the oxygen saturation at referral was investigated in treated and untreated patients. RESULTS Seventy-three patients with visual acuity between 35 and 70 ETDRS letters at referral were treated with intravitreal injection of anti-VEGF compound. Over 12 months, the venous oxygen saturation improved in parallel with central retinal thickness and visual acuity but had no predictive value for visual outcome. In 12 untreated patients with visual acuity >70 ETDRS letters, younger age and high oxygen saturation at the time of referral were positive predictors for the visual outcome after 12 months. CONCLUSION Oxygen saturation, visual acuity and central retinal thickness improve in parallel during treatment of branch retinal vein occlusion with intravitreal anti-VEGF medication. Retinal oximetry at referral cannot predict visual acuity after 12 months in treated patients but may perhaps become a tool for predicting the visual prognosis in a subgroup of patients where treatment is omitted because of a too high visual acuity at the time of diagnosis of the disease.
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Affiliation(s)
- Signe Krejberg Jeppesen
- Department of Ophthalmology Aarhus University Hospital Aarhus N Denmark
- Department of Clinical Medicine Aarhus University Aarhus N Denmark
| | - Toke Bek
- Department of Ophthalmology Aarhus University Hospital Aarhus N Denmark
- Department of Clinical Medicine Aarhus University Aarhus N Denmark
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12
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Heitmar R, Blann AD. Oxygen saturation in retinal vessels and their correlation with endothelial microparticles in diabetes mellitus and/or cardiovascular disease. Microvasc Res 2022; 142:104336. [PMID: 35143812 DOI: 10.1016/j.mvr.2022.104336] [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: 08/08/2021] [Revised: 02/01/2022] [Accepted: 02/01/2022] [Indexed: 10/19/2022]
Abstract
PURPOSE Retinal oxygen supply is a critical requirement in ocular function, and when inadequate can lead to retinopathy. Endothelial dysfunction is a leading pathophysiology in diabetes and cardiovascular disease and may be assessed by endothelial microparticles (EMPs). We hypothesised links between retinal vessel oxygenation and EMPs, expecting these indices to be more adverse in those with both DM and CVD. METHODS Plasma from 34 patients with diabetes mellitus alone (DM), 40 with cardiovascular disease (CVD) alone and 36 with DM plus CVD was probed for EMPs by flow cytometry, but also for vascular markers soluble E-selectin (sEsel) and von Willebrand factor (vWf) (both ELISA). Retinal vessel fractal dimension, lacunarity, calibres and oxygen saturation were assessed from monochromatic and dual wavelength imaging respectively, intra-ocular pressure by was measured by rebound tonometry (I-CARE). RESULTS There was no difference in oxygenation (arterial p = 0.725, venous p = 0.264, arterio-venous difference 0.375) between the groups, but there were differences in EMPs (p = 0.049), vWf (p = 0.004) and sEsel (p = 0.032). In the entire cohort, and in diabetes alone, EMPs correlated with venous oxygenation (r = 0.24, p = 0.009 and r = 0.43, p = 0.011 respectively), while in DM + CVD, sEsel correlated with venous oxygenation (r = 0.55, p = 0.002) and with the arterial-venous difference (r = -0.63, p = 0.001). In multivariate regression analysis of vascular markers against retinal oximetry indices in the entire group, EMPs were positively linked to venous oxygenation (p = 0.037). CONCLUSIONS Despite differences in systemic markers of vascular function between DM, CVD and DM + CVD, there was no difference in arterial or venous retinal oxygenation, or their difference. However, EMPs were linked to venous oximetry, and may provide further insight into the mechanisms underlying diabetes and diabetic retinopathy.
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Affiliation(s)
- R Heitmar
- Aston University, School of Optometry, College of Health and Life Sciences, Aston Triangle, B4 7ET Birmingham, UK; Huddersfield University, Optometry and Vision Sciences, HD1 3DH Huddersfield, UK.
| | - A D Blann
- Huddersfield University, Optometry and Vision Sciences, HD1 3DH Huddersfield, UK; University of Birmingham Institute for Cardiovascular Sciences, City Hospital, Birmingham B18 7QH, UK
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13
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Bek T, Jeppesen SK. Doppler OCT as a tool for studying localized disturbances in blood flow in larger retinal vessels. Acta Ophthalmol 2022; 100:834-835. [PMID: 35113483 DOI: 10.1111/aos.15106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 12/10/2021] [Accepted: 01/20/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Toke Bek
- Department of Ophthalmology Aarhus University Hospital Aarhus N Denmark
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14
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Pappelis K, Jansonius NM. Retinal Oxygen Delivery and Extraction in Ophthalmologically Healthy Subjects With Different Blood Pressure Status. Transl Vis Sci Technol 2022; 11:9. [PMID: 35119472 PMCID: PMC8819358 DOI: 10.1167/tvst.11.2.9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To compare retinal oxygen delivery (DO2) and oxygen extraction (VO2) in ophthalmologically healthy subjects with different blood pressure (BP) status. Methods In this case-control study, we prospectively included 93 eyes of 93 subjects (aged 50-65 years) from a Dutch cohort (n = 167,000) and allocated them to four groups (low BP, normal BP [controls], treated arterial hypertension [AHT], untreated AHT). We estimated vascular calibers from fundus images and fractal dimension from optical coherence tomography angiography scans. We combined calibers, fractal dimension, BP, and intraocular pressure measurements in a proxy of retinal blood flow (RBF), using a Poiseuille-based model. We measured arterial and venous oxygen saturations (SaO2, SvO2) with a scanning laser ophthalmoscope. We calculated the DO2 and VO2 from the RBF, SaO2, and SvO2. We compared the DO2 and VO2 between groups and investigated the DO2-VO2 association. Results DO2 and VO2 were different between groups (P = 0.009, P = 0.036, respectively). In a post hoc analysis, the low BP group had lower DO2 than the untreated AHT group (P = 4.9 × 10-4). The low BP group and the treated AHT group had a lower VO2 than the untreated AHT group (P = 0.021 and P = 0.034, respectively). There was a significant DO2-VO2 correlation (Robs = 0.65, bobs = 0.51, P = 2.4 × 10-12). After correcting for shared measurement error, the slope was not significant. Conclusions The DO2 and VO2 were altered in ophthalmologically healthy subjects with different BP status. Future studies could elucidate whether these changes can explain the increased risk of ophthalmic pathologies in those subjects. Translational Relevance Understanding the baseline interplay between BP, retinal perfusion, and oxygenation allows for improved evaluation of retinal disease manifestation.
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Affiliation(s)
- Konstantinos Pappelis
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.,Graduate School of Medical Sciences (Research School of Behavioural and Cognitive Neurosciences), University of Groningen, Groningen, the Netherlands
| | - Nomdo M Jansonius
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.,Graduate School of Medical Sciences (Research School of Behavioural and Cognitive Neurosciences), University of Groningen, Groningen, the Netherlands
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15
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Krejberg Jeppesen S, Sín M, Hakon Hardarson S, Bek T. Retinal oximetry does not predict 12-month visual outcome after anti-VEGF treatment for central retinal vein occlusion: A multicentre study. Acta Ophthalmol 2021; 99:e1141-e1145. [PMID: 33421320 DOI: 10.1111/aos.14744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 10/28/2020] [Accepted: 12/10/2020] [Indexed: 11/30/2022]
Abstract
PURPOSE Central retinal vein occlusion (CRVO) entails retinal hypoxia that often causes visual impairment. It has been shown that oxygen saturation in larger retinal vessels correlates with the visual acuity at the time of diagnosis of CRVO but has no predictive value for the visual outcome in patients treated with anti-VEGF medication after 3 months. However, assessing the predictive value of retinal oxygen saturation after 12 months is essential because this is when the main restitution after CRVO occurs. METHODS Retinal oximetry was performed in 117 patients referred with CRVO to three European centres. The correlation between oxygen saturation and visual acuity at baseline and the predictive value of oxygen saturation in larger retinal vessels for the 12-month visual outcome after treatment with anti-VEGF medication were studied. RESULTS In the affected eye, the oxygen saturation was significantly higher in the arterioles, significantly lower in the venules, and the arterio-venous (A-V) significantly higher than in the unaffected eye (p < 0.001 for all comparisons). Correlations between best-corrected visual acuity (BCVA) and oxygen saturations were moderate and negative for arterioles (p < 0.001), positive for venules (p = 0.03) and negative for the A-V difference (p = 0.001). Best-corrected visual acuity (BCVA), but not oxygen saturation or the other explanatory variables at baseline, contributed significantly to predicting BCVA after 12 months. CONCLUSION Retinal vessel oxygen saturation is affected in CRVO, and saturation correlates with BCVA. However, retinal oximetry cannot replace measures of visual function as a predictor of visual outcome after 12 months of anti-VEGF treatment for CRVO.
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Affiliation(s)
| | - Martin Sín
- Department of Ophthalmology Faculty of Medicine and dentistry Palacký University Olomouc Olomouc Czech Republic
- Department of Ophthalmology Military University Hospital Prague First Faculty of Medicine Charles University Prague Czech Republic
| | | | - Toke Bek
- Department of Ophthalmology Aarhus University Hospital Aarhus N Denmark
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16
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Abstract
Similar to other organs, the retina relies on tightly regulated perfusion and oxygenation. Previous studies have demonstrated that retinal blood flow is affected in a variety of eye and systemic diseases, including diabetic retinopathy, age-related macular degeneration, and glaucoma. Although measurement of peripheral oxygen saturation has become a standard clinical measurement through the development of pulse oximetry, developing a noninvasive technique to measure retinal oxygen saturation has proven challenging, and retinal oximetry technology currently remains inadequate for reliable clinical use. Here, we review current strategies and approaches, as well as several newer technologies in development, and discuss the future of retinal oximetry.
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Affiliation(s)
- Anupam K Garg
- Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA, USA.,School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Darren Knight
- Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA, USA
| | - Leonardo Lando
- Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA, USA
| | - Daniel L Chao
- Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA, USA.,School of Medicine, University of California San Diego, La Jolla, CA, USA.,Janssen Research and Development, Raritan, NJ, USA
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17
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Hardarson SH, Stefánsson E, Bek T. Retinal oxygen saturation changes progressively over time in diabetic retinopathy. PLoS One 2021; 16:e0251607. [PMID: 33979414 PMCID: PMC8115819 DOI: 10.1371/journal.pone.0251607] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/28/2021] [Indexed: 11/19/2022] Open
Abstract
PURPOSE According to cross-sectional studies, oxygen saturation is elevated in retinal vessels in diabetic patients. We evaluated how retinal oxygenation (metabolic marker), vessel diameters and retinopathy grade (structural markers) change over time in diabetic patients. DESIGN Prospective cohort study following screening in a hospital setting. METHODS Retinal oximetry images were acquired in 214 patients with the Oxymap T1 oximeter. Imaging was repeated after a median of 3.0 years (range 0.76-6.8 years). Oxygen saturation and vessel diameters were measured in the right eye. Semiquantitative grading of retinopathy according to international guidelines and red lesion count were performed on fundus photographs. RESULTS Retinopathy grade according to the international semiquantitative grading system was unchanged. Arteriolar saturation increased by 0.75±0.15 percentage points per year of follow-up (p<0.0001). Venular saturation increased by 1.74±0.26 percentage points per year (p<0.0001) and arteriovenous difference decreased by 0.99±0.20 percentage points per year (p<0.0001). Arteriolar diameters decreased by 2.7±8.5μm (p<0.0001) between visits and venular diameters decreased by 2.4±9.1μm (p = 0.0002). Median increase in red lesion count between visits was 2 lesions (range -128 to 212 lesions, p<0.0001). The change in red lesion count and change in diameters did not correlate with the length of follow-up (p>0.44). CONCLUSIONS Oxygen saturation in larger retinal vessels can increase and arteriovenous difference can decrease over time in diabetic patients without any observable changes in retinopathy grade. The results suggest that changes in retinal oxygen saturation may precede progression of diabetic retinopathy or that oxygen saturation is more sensitive to disease progression than retinopathy grade.
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Affiliation(s)
- Sveinn Hakon Hardarson
- Institute of Physiology, Department of Medicine, University of Iceland, Reykjavik, Iceland
- * E-mail:
| | - Einar Stefánsson
- Institute of Physiology, Department of Medicine, University of Iceland, Reykjavik, Iceland
- Department of Ophthalmology, Landspitali University Hospital, Reykjavik, Iceland
| | - Toke Bek
- Department of Ophthalmology, Aarhus University Hospital, Aarhus N, Denmark
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18
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Bek T, Jeppesen SK. Reduced Oxygen Extraction in the Retinal Periphery When the Arterial Blood Pressure Is Increased by Isometric Exercise in Normal Persons. Invest Ophthalmol Vis Sci 2021; 62:11. [PMID: 33683296 PMCID: PMC7960864 DOI: 10.1167/iovs.62.3.11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Purpose Recent evidence suggests that the smaller retinal vessels are significantly involved in the regulation of retinal blood flow and that this regulation may differ among the macular area and the retinal periphery. An alternative to studying blood flow regulation in smaller retinal vessels that are difficult to resolve is to assess the metabolic consequences of changes in the microcirculation using oximetry. Methods In 20 normal persons aged (mean ± SD, range) 30.1 ± 3.8 (24–37) years, the oxygen saturation and diameter of retinal arterioles and venules to the macular area and the retinal periphery were studied before and during an increase in the arterial blood pressure induced by isometric exercise. Results The isometric exercise increased the mean arterial blood pressure by (mean ± SEM) 10.0 ± 1.1 mm Hg but induced no significant changes in the diameter of the arterioles (P = 0.83). The isometric exercise had no significant effect on the oxygen saturation in the arterioles supplying the macular area and the retinal periphery (P > 0.42 for both comparisons). However, there was a significant increase in the oxygen saturation in venules draining the retinal periphery to reduce the oxygen extraction from (mean ± SEM) 36.0% ± 2.3% to 30.6% ± 2.1% (P = 0.002) but no significant change in the preexisting low oxygen extraction in the macular area that changed from (mean ± SEM) 18.2% ± 3.0% to 16.2% ± 1.9% (P = 0.37). Conclusions Minor changes in the arterial blood pressure can induce changes in retinal rheology with significant regional variation. The finding may help explain regional variations in manifestations of retinal vascular disease such as hyperpermeability in the macular area and capillary occlusion in the retinal periphery.
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Affiliation(s)
- Toke Bek
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
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19
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della Volpe Waizel M, Scholl HPN, Valmaggia C, Todorova MG. Retinal vessel oximetry in children with inherited retinal diseases. Acta Ophthalmol 2021; 99:52-60. [PMID: 32573052 DOI: 10.1111/aos.14466] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 04/21/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND Retinal vessel oximetry (RO) has been used to show altered metabolic function in patients with inherited retinal diseases (IRDs). The aim of this study was to investigate RO parameters of children with IRDs and presumed IRD carriers (pIRDc) and to compare them to controls. METHODS In this cross-sectional cohort study, 142 eyes from 71 Caucasian subjects were included: 40 eyes with IRDs, 26 eyes with pIRDc and 76 control eyes. The oxygen saturation was measured with the Retinal Vessel Analyser (IMEDOS Systems UG, Jena, Germany). Mean oxygen saturations in the peripapillary retinal arterioles (A-SO2 ; %) and venules (V-SO2 ; %) were estimated, and their difference (A-V SO2 ; %) was calculated. In addition, we evaluated the mean diameter in all major retinal arterioles (D-A; μm) and venules (D-V; μm). anova-based linear mixed-effects models were calculated with SPSS® . RESULTS In general, children suffering from IRDs differed from controls when the A-SO2 and A-V SO2 were taken into account: both the A-SO2 and the A-V SO2 were significantly increased (p = 0.012). In subgroup analyses, children suffering from rod-cone dystrophy (RCD) presented an A-SO2 increase (99.12 ± 8.24%) when compared to controls (91.33 ± 10.34%, p = 0.014) and pIRDc (92.37 ± 6.57%, p = 0.065). For V-SO2 significant changes in RCD (67.42 ± 9.19%) were found in comparison with controls (58.24 ± 11.74%, p < 0.041), pIRDc (56.67 ± 7.16%, p = 0.007), cone-rod dystrophies (CRD, 52.17 ± 5.32%, p < 0.001) and inherited macular dystrophies (IMD, 55.74 ± 6.96%, p = 0.004), In addition, A-V SO2 was decreased in RCD (31.69 ± 3.92%) when measured against CRD (41.9 ± 8.87%, p = 0.017) or IMD (39.52 ± 8.95%, p = 0.059). CONCLUSION In general, we found that children with IRDs presented early metabolic changes. Within IRDs, children with RCD showed more affected metabolic changes. Thus, RO may support early screening to rule out IRDs in children, and more precisely may help to differentiate those suffering from RCD.
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Affiliation(s)
- Maria della Volpe Waizel
- Department of Ophthalmology University of Basel Basel Switzerland
- Institute of Molecular and Clinical Ophthalmology Basel (IOB) Basel Switzerland
| | - Hendrik P. N. Scholl
- Department of Ophthalmology University of Basel Basel Switzerland
- Institute of Molecular and Clinical Ophthalmology Basel (IOB) Basel Switzerland
| | - Christophe Valmaggia
- Department of Ophthalmology University of Basel Basel Switzerland
- Department of Ophthalmology Cantonal Hospital St. Gallen St. Gallen Switzerland
| | - Margarita G. Todorova
- Department of Ophthalmology University of Basel Basel Switzerland
- Department of Ophthalmology Cantonal Hospital St. Gallen St. Gallen Switzerland
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20
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Zhang W, Li L, Zou D, Ren Q, Zhang Y, Kang L, Gu X, Wu H, Zhang S, Zhu R, Zhang Y, Yang L. Retinal vessel oxygen saturation in patients with unilateral internal carotid artery stenosis: a pilot study. Acta Ophthalmol 2021; 99:e13-e18. [PMID: 32519804 DOI: 10.1111/aos.14503] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 05/17/2020] [Indexed: 12/30/2022]
Abstract
PURPOSE To investigate the retinal vessel oxygen saturation in patients with internal carotid artery stenosis (ICAS). METHODS This is a cross-sectional study. Sixteen patients with unilateral moderate or worse ICAS (≥50%) and no fundus diseases were included in the study. Sixteen gender- and age-matched healthy subjects were selected as controls. The mean oxygen saturation and vessel diameters of the retinal arterioles and venules were obtained using a dual-wavelength spectrophotometric retinal oximeter. RESULTS In the eye of the stenotic side, the retinal vessel oxygen saturation was 100.14 ± 10.27% in the arterioles and 56.50 ± 10.79% in the venules, and the arteriovenous (A-V) difference was 43.63 ± 7.71%. In the eye of the contralateral side, the oxygen saturation was 96.55 ± 7.50% in the arterioles and 57.42 ± 9.84% in the venules, and the A-V difference was 39.39 ± 6.33%. In healthy subjects, the oxygen saturation was 93.22 ± 5.98% in the arterioles and 56.57 ± 7.05% in the venules, and the A-V difference was 36.65 ± 7.33%. The arteriolar oxygen saturation in the stenotic side was higher than that in the contralateral side (p = 0.025) and that in the healthy subjects (p = 0.027), and the A-V difference in the stenotic side was significantly higher than that in the contralateral side (p = 0.009) and that in the healthy subjects (p = 0.013). The diameters of the arterioles in the stenotic side were smaller than those in the healthy subjects (p = 0.030). CONCLUSIONS Patients with ICAS had decreased retinal arteriole diameters and increased retinal vessel oxygen saturation in the arterioles and A-V differences, suggesting the presence of microcirculation disorder and hyperoxia in the retina.
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Affiliation(s)
- Wenbo Zhang
- Department of Ophthalmology Peking University First Hospital Beijing China
| | - Liangliang Li
- Department of Ultrasonography Peking University First Hospital Beijing China
| | - Da Zou
- Department of Biomedical Engineering College of Engineering Peking University Beijing China
| | - Qiushi Ren
- Department of Biomedical Engineering College of Engineering Peking University Beijing China
| | - Yadi Zhang
- Department of Ophthalmology Peking University First Hospital Beijing China
| | - Lei Kang
- Department of Ophthalmology Peking University First Hospital Beijing China
| | - Xiaopeng Gu
- Department of Ophthalmology Peking University First Hospital Beijing China
| | - Hailong Wu
- Department of Ophthalmology Peking University First Hospital Beijing China
| | - Shijie Zhang
- Department of Ophthalmology Peking University First Hospital Beijing China
| | - Ruilin Zhu
- Department of Ophthalmology Peking University First Hospital Beijing China
| | - Yanzhen Zhang
- Department of Ophthalmology Peking University First Hospital Beijing China
| | - Liu Yang
- Department of Ophthalmology Peking University First Hospital Beijing China
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21
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Tomita R, Iwase T, Ueno Y, Goto K, Yamamoto K, Ra E, Terasaki H. Differences in Blood Flow Between Superior and Inferior Retinal Hemispheres. Invest Ophthalmol Vis Sci 2020; 61:27. [PMID: 32421146 PMCID: PMC7405729 DOI: 10.1167/iovs.61.5.27] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To determine whether the blood flow in the superior retina is significantly different from that in the inferior retina, and to determine whether the posture affects the blood flow in the superior and inferior retina. Methods The blood flow in the vessels around the optic nerve head was measured by laser speckle flowgraphy in the sitting position in 68 healthy subjects. The blood flow in the superior peripapillary retina was compared with that in the inferior peripapillary retina. The measurements of the blood flow were performed in the sitting position, and the effect of switching to a supine position was determined at 2, 4, 6, 8, 10, and 30 minutes after the switch. Results The total relative flow volume (RFV)-all, RFV-artery, and RFV-vein were significantly greater in the superior retina than in the inferior retina (all P < 0.001). The mean diameter-all and mean diameter-artery in the superior retina were significantly larger than that in the inferior retina (all P < 0.05). The mean blur rate (MBR)-all, MBR-artery, and MBR-vein in the superior retina were also greater than that in the inferior retina (P < 0.001, P < 0.01, and P < 0.001, respectively). Although the ocular perfusion pressure was significantly changed with the postural alteration, the total RFV-all remained greater in the superior retina than in the inferior retina after the postural change. Conclusions Clinicians need to be aware of the differences in the blood flow between the superior and inferior retinal peripapillary area when considering the mechanisms of retinochoroidal diseases.
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Shughoury A, Mathew S, Arciero J, Wurster P, Adjei S, Ciulla T, Siesky B, Harris A. Retinal oximetry in glaucoma: investigations and findings reviewed. Acta Ophthalmol 2020; 98:559-571. [PMID: 32248646 DOI: 10.1111/aos.14397] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 02/20/2020] [Indexed: 12/17/2022]
Abstract
Abnormalities of the retinal blood supply have been widely implicated in primary open-angle glaucoma (POAG). Impaired blood supply to the retina and optic nerve head (ONH) may be a primary pathophysiologic mechanism contributing to POAG ('vascular hypothesis'). However, the decreased metabolic activity of atrophic tissue is itself known to induce both vascular changes and decreased blood flow due to reduced oxygen demand. Therefore, primary nonvascular factors could potentially induce glaucomatous atrophy, with subsequent secondary vascular pathology ('mechanical hypothesis'). Retinal oximetry holds great promise in the investigation of glaucoma pathogenesis, as it can provide useful data on retinal metabolic oxygen demand, especially when combined with measurements of retinal blood flow. This review surveys the research on retinal metabolism in POAG using spectroscopic retinal oximetry. The use of mathematical models in combination with oximetric data to investigate the role of retinal metabolism and oxygen supply in POAG is also discussed.
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Affiliation(s)
- Aumer Shughoury
- Eugene and Marilyn Glick Eye Institute Department of Ophthalmology Indiana University School of Medicine Indianapolis IN USA
| | - Sunu Mathew
- Eugene and Marilyn Glick Eye Institute Department of Ophthalmology Indiana University School of Medicine Indianapolis IN USA
| | - Julia Arciero
- Department of Mathematical Sciences Indiana University Purdue University Indianapolis IN USA
| | - Patrick Wurster
- Eugene and Marilyn Glick Eye Institute Department of Ophthalmology Indiana University School of Medicine Indianapolis IN USA
| | - Susuana Adjei
- Eugene and Marilyn Glick Eye Institute Department of Ophthalmology Indiana University School of Medicine Indianapolis IN USA
| | | | - Brent Siesky
- Icahn School of Medicine at Mount Sinai New York NY USA
| | - Alon Harris
- Icahn School of Medicine at Mount Sinai New York NY USA
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Bata AM, Fondi K, Szegedi S, Aschinger GC, Hommer A, Schmidl D, Chua J, Werkmeister RM, Garhöfer G, Schmetterer L. Age-Related Decline of Retinal Oxygen Extraction in Healthy Subjects. Invest Ophthalmol Vis Sci 2019; 60:3162-3169. [PMID: 31335953 DOI: 10.1167/iovs.18-26234] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To investigate the age-dependence of total retinal blood flow and total retinal oxygen extraction in healthy subjects and determine their possible correlations with structural optical coherence tomography (OCT) parameters. Methods This observational cross-sectional study consisted of 68 healthy subjects (mean ± SD age, 45.6 ± 16.3 years; 47% female). Total retinal oxygen extraction was calculated based on measurement of total retinal blood flow using bi-directional Doppler OCT and measurement of oxygen saturation using spectroscopic reflectometry. Retinal nerve fiber layer thickness was measured using OCT, and the total number of retinal ganglion cells was estimated based on a previous published model. Correlation of these parameters with age was studied and the association between structural OCT parameters and hemodynamic vascular parameters was calculated. Results Both structural and vascular parameters showed a significant decline with increasing age. The correlation coefficients were between r = -0.25 and r = -0.41. Furthermore, structural and vascular parameters were significantly correlated with each other. The strongest association was found between the level of total retinal oxygen extraction and the number of retinal ganglion cells (r = 0.75, P < 0.001). Conclusions We showed that there was an age-related decline of retinal oxygen extraction. Levels of retinal oxygen extraction are correlated to retinal nerve fiber layer thickness and number of retinal ganglion cells. Our data partially explain the wide inter-individual variability in retinal blood flow values in healthy subjects. Longitudinal studies are required to study the time course of vascular and neuronal loss in humans.
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Affiliation(s)
- Ahmed M Bata
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Klemens Fondi
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Stephan Szegedi
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Gerold C Aschinger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Anton Hommer
- Department of Clinical Pharmacology, Medical University of Vienna, Austria.,Department of Ophthalmology, Sanatorium Hera, Vienna, Austria
| | - Doreen Schmidl
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Jacqueline Chua
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore
| | - René M Werkmeister
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria
| | - Gerhard Garhöfer
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
| | - Leopold Schmetterer
- Department of Clinical Pharmacology, Medical University of Vienna, Austria.,Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Austria.,Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.,Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
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24
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Petersen L, Bek T. The Oxygen Saturation in Vascular Abnormalities Depends on the Extent of Arteriovenous Shunting in Diabetic Retinopathy. ACTA ACUST UNITED AC 2019; 60:3762-3767. [DOI: 10.1167/iovs.19-27472] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Line Petersen
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
| | - Toke Bek
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
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25
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Bek T, Stefánsson E, Hardarson SH. Retinal oxygen saturation is an independent risk factor for the severity of diabetic retinopathy. Br J Ophthalmol 2018; 103:1167-1172. [PMID: 30337331 DOI: 10.1136/bjophthalmol-2018-312764] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/11/2018] [Accepted: 09/17/2018] [Indexed: 12/17/2022]
Abstract
BACKGROUND The oxygen saturation in larger retinal vessels has been shown to increase with increasing diabetic retinopathy (DR) grade and to help predict the effect of antivascular endothelial growth factor treatment in patients with diabetic maculopathy. However, it is unknown to what extent the increased oxygen saturation co-varies with other risk factors and whether it is an independent risk factor for the severity of DR. METHODS Seven hundred and twenty-two successive patients referred for specialist evaluation of diabetic retinopathy including retinal oximetry were studied. Multiple regression analysis was used to investigate whether oxygen saturation in the larger retinal arterioles and venules contributed to the severity of diabetic retinopathy, independently of gender, age, diabetes duration, diabetes type, body mass index, blood pressure, haemoglobin A1c, visual acuity and central retinal thickness. RESULTS The included parameters could explain less than 15% of the variation in retinopathy grade. Approximately, one-third of the explained variation was related to the retinal oxygen saturation. CONCLUSIONS Prospective studies are needed to evaluate whether retinal oxygen saturation is predictive for the development of diabetic retinopathy and how it interacts with other biomarkers and risk factors over time.
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Affiliation(s)
- Toke Bek
- Departments of Ophthalmology, University of Iceland, Reykjavik, Iceland
| | - Einar Stefánsson
- Departments of Physiology, University of Iceland, Reykjavik, Iceland.,Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
| | - Sveinn Hákon Hardarson
- Departments of Physiology, University of Iceland, Reykjavik, Iceland.,Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
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