1
|
Gocuk SA, Hadoux X, Catipon C, Cichello E, Kumar H, Jolly JK, van Wijngaarden P, Llewelyn Edwards T, Ayton LN, Sousa DC. Retinal vascular reactivity in carriers of X-linked inherited retinal disease - a study using optical coherence tomography angiography. FRONTIERS IN OPHTHALMOLOGY 2024; 4:1415393. [PMID: 39045093 PMCID: PMC11263797 DOI: 10.3389/fopht.2024.1415393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 06/24/2024] [Indexed: 07/25/2024]
Abstract
Purpose Female carriers of X-linked inherited retinal diseases (IRDs) can show highly variable phenotypes and disease progression. Vascular reactivity, a potential disease biomarker, has not been investigated in female IRD carriers. In this study, functional optical coherence tomography angiography (OCT-A) was used to dynamically assess the retinal microvasculature of X-linked IRD carriers. Methods Genetically confirmed female carriers of IRDs (choroideremia or X-linked retinitis pigmentosa), and healthy women were recruited. Macular angiograms (3x3mm, Zeiss Plex Elite 9000) were obtained in 36 eyes of 15 X-linked IRD female carriers and 21 age-matched control women. Two tests were applied to test vascular reactivity: (i) mild hypoxia and (ii) handgrip test, to induce a vasodilatory or vasoconstrictive response, respectively. Changes to vessel density (VD) and vessel length density (VLD) were independently evaluated during each of the tests for both the superficial and deep capillary plexuses. Results In the control group, the superficial and deep VD decreased during the handgrip test (p<0.001 and p=0.037, respectively). Mean superficial VLD also decreased during the handgrip test (p=0.025), while the deep plexus did not change significantly (p=0.108). During hypoxia, VD and VLD increased in the deep plexus (p=0.027 and p=0.052, respectively) but not in the superficial plexus. In carriers, the physiologic vascular responses seen in controls were not observed in either plexus during either test, with no difference in VD or VLD noted (all p>0.05). Conclusions Functional OCT-A is a useful tool to assess dynamic retinal microvascular changes. Subclinical impairment of the physiological vascular responses seen in carriers of X-linked IRDs may serve as a valuable clinical biomarker.
Collapse
Affiliation(s)
- Sena Ayse Gocuk
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, VIC, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia
| | - Xavier Hadoux
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia
| | - Charmaine Catipon
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
| | - Elise Cichello
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
| | - Himeesh Kumar
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia
| | - Jasleen Kaur Jolly
- Vision and Eye Research Institute, Anglia Ruskin University, Cambridge, United Kingdom
| | - Peter van Wijngaarden
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia
| | - Thomas Llewelyn Edwards
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia
| | - Lauren Nicole Ayton
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, VIC, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia
| | - David Cordeiro Sousa
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia
| |
Collapse
|
2
|
Retinal microvasculature and vasoreactivity changes in hypertension using optical coherence tomography-angiography. Graefes Arch Clin Exp Ophthalmol 2022; 260:3505-3515. [PMID: 35678840 DOI: 10.1007/s00417-022-05706-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 04/21/2022] [Accepted: 05/14/2022] [Indexed: 11/04/2022] Open
Abstract
PURPOSE To evaluate the retinal vasculature and vasoreactivity of patients with hypertension (HTN) using spectral domain optical coherence tomography angiography (SD-OCTA). METHODS Patients with and without a diagnosis of HTN were included in this cross-sectional observational study. All eyes were imaged with SD-OCTA using 3 mm × 3 mm and 6 mm × 6 mm centered on both the fovea and optic disk. A second 6 mm × 6 mm scan was taken after a 30 s breath-hold. Vessel density (VD), vessel skeletonized density (VSD), and fractal dimension (FD) were calculated using customized MATLAB scripts. Vessel diameter index (VDI) was obtained by taking the ratio of VD to VSD. Vasoreactivity was measured by subtracting the VD or VSD before and after breath-hold (∆VD, ∆VSD). RESULTS Twenty-three eyes with HTN (17 patients) and 17 control eyes (15 patients) were included. In the 6 mm × 6 mm angiogram centered on fovea, the superficial capillary plexus (SCP) VD (ß = - 0.029, p = 0.012), VSD (ß = - 0.004, p = 0.043) and the choriocapillaris VD (ß = - 0.021, p = 0.030) were significantly decreased in HTN compared to control eyes. Similarly, FD was decreased in both the SCP (ß = - 0.012, p = 0.013) and choriocapillaris (ß = - 0.009, p = 0.030). In the 3 mm × 3 mm angiogram centered on optic disk, SCP VDI (ß = - 0.364, p = 0.034) was decreased. ∆VD and ∆VSD were both reduced in the DCP (ß = - 0.034, p = 0.032; ß = - 0.013, p = 0.043) and ∆VSD was elevated in the choriocapillaris of HTN eyes (ß = 0.004, p = 0.032). CONCLUSIONS The study used SD-OCTA to show significant differences in the retinal vasculature of hypertensive patients. It was also the first to demonstrate the potential of OCT-A to investigate retinal vascular reactivity in patients with HTN.
Collapse
|
3
|
Düzgün E, Şahin T, Yeşiltaş SK, Alkan AA, Dikmen NT. Ozone-induced retinal vascular reactivity as assessed by optical coherence tomography angiography. Photodiagnosis Photodyn Ther 2022; 39:102957. [PMID: 35690324 DOI: 10.1016/j.pdpdt.2022.102957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 05/18/2022] [Accepted: 06/07/2022] [Indexed: 11/26/2022]
Abstract
BACKGROUND This study aimed to investigate the retinal vascular reactivity (RVR) of the macular and peripapillary capillary network in response to ozonated autohemotherapy (AHT) using optical coherence tomography angiography (OCTA). METHODS This was a single-centre prospective study. All participants that were planned to have a combination of major and minor ozone AHT underwent a complete ocular examination and OCTA imaging before and after the ozone AHT. Foveal avascular zone (FAZ) metrics and vessel density (VD) of superficial (SCP), deep capillary plexus (DCP), and radial peripapillary capillary (RPC) plexus were assessed using the built-in software. RESULTS A total of 40 right eyes of 40 individuals were included. No significant differences were observed for the mean values of the FAZ metrics and choriocapillaris flow area following ozone AHT compared with baseline values (p > 0.05). The mean whole VD of SCP and DCP was 47.80 ± 2.18% and 53.09 ± 3.00% before treatment, which decreased to 47.68 ± 2.7% and 52.38 ± 3.07% after treatment (p = 0.660 and p = 0.097, respectively). No significant differences were observed in the vascular densities of both SCP and DCP in any quadrant (p > 0.05). The RPC density did not show significant alterations compared with baseline values, except the inferior-hemi region. The VD in the inferior-hemi peripapillary quadrant was significantly increased after ozone AHT (p = 0.034). CONCLUSION The ozone AHT did not cause evident RVR in the macular area, whereas the peripapillary area showed a partial response.
Collapse
Affiliation(s)
- Eyüp Düzgün
- Department of Ophthalmology, Sisli Hamidiye Etfal Training and Research Hospital, University of Health Sciences, Istanbul, Turkey.
| | - Tülay Şahin
- Department of Physical Therapy and Rehabilitation, Sisli Hamidiye Etfal Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Sümeyra Keleş Yeşiltaş
- Department of Ophthalmology, Sisli Hamidiye Etfal Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Abdurrahman Alpaslan Alkan
- Department of Ophthalmology, Sisli Hamidiye Etfal Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| | - Nejla Tükenmez Dikmen
- Department of Ophthalmology, Sultan Abdulhamid Han Training and Research Hospital, University of Health Sciences, Istanbul, Turkey
| |
Collapse
|
4
|
Blanco-Hernández DMR, Somilleda-Ventura SA, Chávez-Herrera R, Colas-Calvere MG, Lima-Gómez V. Compensatory contribution of retinal larger vessels to perfusion density in diabetics without retinopathy. Sci Rep 2022; 12:329. [PMID: 35013324 PMCID: PMC8748763 DOI: 10.1038/s41598-021-02554-y] [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] [Received: 06/14/2021] [Accepted: 11/10/2021] [Indexed: 11/25/2022] Open
Abstract
Vessel and perfusion densities may decrease before diabetic retinopathy appears; it is unknown whether these changes affect the contribution of vessel density to perfusion density. This was a non-experimental, comparative, prospective, cross-sectional study in non-diabetic subjects (group 1) and diabetics without retinopathy (group 2). Vessel and perfusion densities in the superficial capillary plexus were compared between groups at the center, inner, and full regions and by field (superior, temporal, inferior, nasal) using optical coherence tomography angiography. Coefficients of determination (R2) between vessel and perfusion densities were calculated to find the contribution of larger retinal vessels to perfusion density. Percent differences were used to evaluate the contribution of these vessels to perfusion density in a regression model. There were 62 participants, 31 eyes by group; vessel and perfusion densities as well as the coefficients of determination between them were lower in group 2, especially in the nasal field (R2 0.85 vs. 0.71), which showed a higher contribution of larger retinal vessels to perfusion density. The regression model adjusted to a quadratic equation. In diabetics without retinopathy the contribution of vessel density to perfusion density may decrease; a low vessel density may increase the contribution of larger retinal vessels to perfusion density.
Collapse
Affiliation(s)
| | | | - Rebeca Chávez-Herrera
- Medicine School, Universidad Autonoma de Ciudad Juarez, 32315, Ciudad Juarez, Mexico
| | | | - Virgilio Lima-Gómez
- Ophthalmology Service, Hospital Juarez de Mexico, 07760, Mexico City, Mexico.
| |
Collapse
|
5
|
Abdolahi F, Zhou X, Ashimatey BS, Chu Z, Jiang X, Wang RK, Kashani AH. Optical Coherence Tomography Angiography-Derived Flux As a Measure of Physiological Changes in Retinal Capillary Blood Flow. Transl Vis Sci Technol 2021; 10:5. [PMID: 34342607 PMCID: PMC8340668 DOI: 10.1167/tvst.10.9.5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Purpose To compare optical coherence tomography angiography (OCTA)–derived flux with conventional OCTA measures of retinal vascular density in assessment of physiological changes in retinal blood flow. Methods Healthy subjects were recruited, and 3 × 3-mm2 fovea-centered scans were acquired using commercially available swept-source OCTA (SS-OCTA) while participants were breathing room air, 100% O2, or 5% CO2. Retinal perfusion was quantified using vessel area density (VAD) and vessel skeleton density (VSD), as well as novel measures of retinal perfusion, vessel area flux (VAF) and vessel skeleton flux (VSF). Flux is proportional to the number of red blood cells moving through a vessel segment per unit time. The percentage change in each measure was compared between the O2 and CO2 gas conditions for images of all vessels (arterioles, venules, and capillaries) and capillary-only images. Statistical significance was determined using paired t-tests and a linear mixed-effects model. Results Eighty-four OCTA scans from 29 subjects were included (age, 45.9 ± 19.5 years; 14 male, 48.3%). In capillary-only images, the change under the CO2 condition was 168% greater in VAF than in VAD (P = 0.002) and 124% greater in VSF than in VSD (P = 0.004). Similarly, under the O2 condition, the change was 94% greater in VAF than in VAD (P = 0.004) and 57% greater in VSF than in VSD (P = 0.01). Flux measures showed significantly greater change in capillary-only images compared with all-vessels images. Conclusions OCTA-derived flux measures quantify physiological changes in retinal blood flow at the capillary level with a greater effect size than conventional vessel density measures. Translational Relevance OCTA-derived flux is a useful measure of subclinical changes in retinal capillary perfusion.
Collapse
Affiliation(s)
- Farzan Abdolahi
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA
| | - Xiao Zhou
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Bright S Ashimatey
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Zhongdi Chu
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Xuejuan Jiang
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA.,Department of Ophthalmology, University of Washington Seattle, WA, USA
| | - Amir H Kashani
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA
| |
Collapse
|
6
|
Past, present and future role of retinal imaging in neurodegenerative disease. Prog Retin Eye Res 2021; 83:100938. [PMID: 33460813 PMCID: PMC8280255 DOI: 10.1016/j.preteyeres.2020.100938] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 12/11/2020] [Accepted: 12/17/2020] [Indexed: 02/08/2023]
Abstract
Retinal imaging technology is rapidly advancing and can provide ever-increasing amounts of information about the structure, function and molecular composition of retinal tissue in humans in vivo. Most importantly, this information can be obtained rapidly, non-invasively and in many cases using Food and Drug Administration-approved devices that are commercially available. Technologies such as optical coherence tomography have dramatically changed our understanding of retinal disease and in many cases have significantly improved their clinical management. Since the retina is an extension of the brain and shares a common embryological origin with the central nervous system, there has also been intense interest in leveraging the expanding armamentarium of retinal imaging technology to understand, diagnose and monitor neurological diseases. This is particularly appealing because of the high spatial resolution, relatively low-cost and wide availability of retinal imaging modalities such as fundus photography or OCT compared to brain imaging modalities such as magnetic resonance imaging or positron emission tomography. The purpose of this article is to review and synthesize current research about retinal imaging in neurodegenerative disease by providing examples from the literature and elaborating on limitations, challenges and future directions. We begin by providing a general background of the most relevant retinal imaging modalities to ensure that the reader has a foundation on which to understand the clinical studies that are subsequently discussed. We then review the application and results of retinal imaging methodologies to several prevalent neurodegenerative diseases where extensive work has been done including sporadic late onset Alzheimer's Disease, Parkinson's Disease and Huntington's Disease. We also discuss Autosomal Dominant Alzheimer's Disease and cerebrovascular small vessel disease, where the application of retinal imaging holds promise but data is currently scarce. Although cerebrovascular disease is not generally considered a neurodegenerative process, it is both a confounder and contributor to neurodegenerative disease processes that requires more attention. Finally, we discuss ongoing efforts to overcome the limitations in the field and unmet clinical and scientific needs.
Collapse
|
7
|
Singer M, Ashimatey BS, Zhou X, Chu Z, Wang R, Kashani AH. Impaired layer specific retinal vascular reactivity among diabetic subjects. PLoS One 2020; 15:e0233871. [PMID: 32915787 PMCID: PMC7485884 DOI: 10.1371/journal.pone.0233871] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 08/29/2020] [Indexed: 01/04/2023] Open
Abstract
PURPOSE To investigate layer specific retinal vascular reactivity (RVR) in capillaries of diabetic subjects without DR or with only mild non-proliferative diabetic retinopathy (NPDR). METHODS A previously described nonrebreathing apparatus was used to deliver room air, 5% CO2, or 100% O2 to 41 controls and 22 diabetic subjects (with mild or no NPDR) while simultaneously acquiring fovea-centered 3x3mm2 Swept-Source Optical Coherence Tomography Angiography (SS-OCTA) images. Vessel skeleton density (VSD) and vessel diameter index (VDI) were calculated for each gas condition for the superficial retinal layer (SRL) and deep retinal layer (DRL). The superficial layer analysis excluded arterioles and venules. Data analysis was performed using mixed factorial analysis of covariance stratified by diabetic status. All models were adjusted for age, gender, and hypertension, and statistical significance for multiple comparisons from posthoc comparisons were defined at p<0.017. RESULTS Among controls, there was a significant difference in capillary VSD between all gas conditions (p<0.001). This difference was present in both the SRL and DRL. Among diabetics, there was no significant difference in response to CO2 conditions in the SRL (p = 0.072), and a blunted response to both CO2 (p = 0.9) and O2 in the DRL (p = 0.019). A significant gas effect was detected in the capillary VDI in the SRL of controls (p = 0.001), which was driven by higher VDI in the oxygen condition compared to that of carbon dioxide. CONCLUSIONS Impairment in RVR in diabetic subjects is characterized by a paradoxical response to CO2 in both the SRL and DRL as well as an attenuated response to O2 in the DRL. These layer and gas specific impairments in diabetics seem to occur early in the disease and to be driven primarily at the capillary level.
Collapse
Affiliation(s)
- Maxwell Singer
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, California, United States of America
| | - Bright S. Ashimatey
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, California, United States of America
| | - Xiao Zhou
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Zhongdi Chu
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Ruikang Wang
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
- Department of Ophthalmology, University of Washington, Seattle, Washington, United States of America
| | - Amir H. Kashani
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, California, United States of America
- USC Ginsburg Institute for Biomedical Therapeutics, Keck School of Medicine of the University of Southern California, Los Angeles, California, United States of America
- * E-mail: ,
| |
Collapse
|