Evaluation of microvasculature alterations in convalescent Vogt-Koyanagi-Harada disease using optical coherence tomography angiography

Optical Coherence Tomography Angiography in Vogt-Koyanagi-Harada Patients: A Systematic Review and Meta-Analysis

PURPOSE

To describe the choroidal retinal microvascular system in Vogt-Koyanagi-Harada (VKH) subjects and furnish additional proof for the early authentication and treatment of VKH suffers.

METHODS

From the beginning to July 2023, a comprehensive search for issued articles on optical coherence tomography angiography (OCTA) among VKH sufferers was implemented in Embase, PubMed, and Web of Science databases. This meta-analysis included 9 eligible studies. Primary endpoints included four kinds of vascular densities, such as superficial capillaris plexus (SCP), deep capillaris plexus (DCP), and choriocapillary (CC). In addition to these, there were foveal avascular zone (FAZ), central retinal thickness (CT), best-corrected distance visual acuity (BCVA log MAR), and subfoveal choroidal thickness (SFCT).

RESULTS

SCP and DCP vessel densities in maculas were both smaller in VKH sufferers in the active stage than those normal and remission examinees (SCP vessel density, p < 0.00001, DCP vessel density, p < 0.00001). Compared to remission, CC vascular density was lower during the active phase. (p < 0.00001). SFCT and CT in the active phase exceeded those in normal and remission examinees (all of them p < 0.00001). In terms of the patients with remission, their FAZ was bigger than that in normal subjects. (MD =0.04, p < 0.0001).

CONCLUSIONS

Retinal and choroidal microvasculatures are characteristically changed in active VKH patients, which suggests that OCTA can be used as a tool for VKH follow-up.

Early and Late Treatment Influence on Chorioretinal Microvasculature in Vogt-Koyanagi-Harada Patients Using Optical Coherence Tomography Angiography

Purpose

To study the impact of early and late treatment on chorioretinal microvasculature in Vogt-Koyanagi-Harada (VKH) disease using optical coherence tomography angiography (OCTA).

Methods

A total of 103 patients with VKH disease were divided into early (group 1, starting treatment within 2 months after disease onset) and late (group 2, starting treatment 2 months after disease onset) treatment groups. Flow area (FA) and vessel density (VD) of the retinal superficial vascular complex (SVC) and deep vascular complex (DVC), FA of the choriocapillaris, three-dimensional choroidal vascular volume (CVV), and choroidal vascularity index (CVI) were analyzed and compared to 103 healthy individuals. The relationship between the final best-corrected visual acuity (BCVA) and the aforementioned parameters was also analyzed.

Results

FA of the SVC (all P < 0.05, except 0-1 mm P = 0.087), DVC (all P < 0.05), choriocapillaris (1-2.5 mm P = 0.033), and CVV (all P < 0.05) were lower in group 2 as compared to group 1. Compared to healthy controls, FA of the SVC (all P < 0.001, except 0-1 mm P = 0.104) and DVC (all P < 0.05), VD of the SVC (1-2.5 mm P = 0.001) and DVC (1-5 mm P = 0.003, 2.5-5 mm P < 0.001), FA of the choriocapillaris (all P < 0.05), and CVV (total area P = 0.049, 1-5 mm P = 0.045, 2.5-5 mm P = 0.041) were lower in group 2, while FA (all P < 0.05, except 0-1 mm P = 0.925) and VD (1-5 mm P = 0.003, 2.5-5 mm P = 0.004) of the DVC and FA of the choriocapillaris (total area P = 0.007, 0-1 mm P < 0.001, 1-2.5 mm P = 0.007) were lower in group 1. There was no significant difference concerning CVI among groups (all P > 0.05). FA of the SVC, DVC, and choriocapillaris and VD of DVC and CVI were negatively associated with the final logarithm of the minimum angle of resolution BCVA.

Conclusions

Patients with VKH disease who are treated within 2 months of disease onset showed a better chorioretinal microvascular outcome as defined by OCTA compared to those treated late.

Translational Relevance

Our study employs OCTA to design three-dimensional metrics for the retina and choroid, bridging the gap between traditional two-dimensional OCTA findings and enhanced clinical outcomes for patients with VKH disease.

The Role of Widefield Optical Coherence Tomography Angiography in the Diagnosis and Management of Acute Vogt-Koyanagi-Harada Disease

PURPOSE

We explore the choroid vasculature changes of acute Vogt-Koyanagi-Harada (VKH) disease using widefield optical coherence tomography angiography (OCTA).

METHODS

In this retrospective, observational, longitudinal study, 16 patients with acute VKH disease (32 eyes, mean age: 42.19 ±13.66 years) were measured using widefield OCTA.

RESULTS

In this study, we first described the multiple dark foci in choriocapillaris and Sattler's layer in the panoramic montage of the five 12x12mm images in 30 eyes (93.8%) of acute VKH disease. OCTA follow-up in these 30 eyes demonstrated the diminished size and number of these dark foci in choriocapillaris and Sattler's layer after the initiation of treatment.

CONCLUSIONS

Widefield OCTA enables noninvasive identification of characteristics of flow void at the level of superficial choroidal vessels in the acute phase and may be a novel valuable tool for diagnosis and monitoring of disease progression in VKH disease in the future.

SS OCT and OCT-A Findings in Convalescent Inactive Vogt-Koyanagi-Harada Disease

PURPOSE

This study aimed to determine predictive factors for low final visual acuity in patients with inactive Vogt-Koyanagi-Harada (VKH) disease using Swept-source OCT and OCT-angiography (OCT-A).

METHODS

We conducted a prospective longitudinal study, including 21 patients (42 eyes), who were followed up for the first 24 months after disease onset. Patients were included at the acute phase and subsequently treated. Sequential qualitative and quantitative changes in OCT and OCT-A were assessed. Analytical statistical methods were employed to determine predictive factors for final visual acuity.

RESULTS

Structural alterations including focal parafoveal outer nuclear layer atrophy, ellipsoid zone disruption, interdigitation zone disruption, and irregular and thickened retinal pigment epithelium line were observed in 57.1% of eyes at month 3, with no significant improvement over time. The presence of flow voids at months 6, 12, and 24 was significantly associated with low final visual acuity. Serous retnal detachment at presentation emerged as an independent risk factor for structural changes detected by SS-OCT during the first 2 years of the disease. Optic disc edema was predictive factor for both structural SS-OCT and OCT-A changes.

CONCLUSION

This study underscores the importance of monitoring flow voids to predict final visual acuity and highlights the impact of serous retinal detachment at presentation on structural changes in patients with inactive VKH disease.

Optical coherence tomography angiography analysis methods: a systematic review and meta-analysis

Optical coherence tomography angiography (OCTA) is widely used for non-invasive retinal vascular imaging, but the OCTA methods used to assess retinal perfusion vary. We evaluated the different methods used to assess retinal perfusion between OCTA studies. MEDLINE and Embase were searched from 2014 to August 2021. We included prospective studies including ≥ 50 participants using OCTA to assess retinal perfusion in either global retinal or systemic disorders. Risk of bias was assessed using the National Institute of Health quality assessment tool for observational cohort and cross-sectional studies. Heterogeneity of data was assessed by Q statistics, Chi-square test, and I2 index. Of the 5974 studies identified, 191 studies were included in this evaluation. The selected studies employed seven OCTA devices, six macula volume dimensions, four macula subregions, nine perfusion analyses, and five vessel layer definitions, totalling 197 distinct methods of assessing macula perfusion and over 7000 possible combinations. Meta-analysis was performed on 88 studies reporting vessel density and foveal avascular zone area, showing lower retinal perfusion in patients with diabetes mellitus than in healthy controls, but with high heterogeneity. Heterogeneity was lowest and reported vascular effects strongest in superficial capillary plexus assessments. Systematic review of OCTA studies revealed massive heterogeneity in the methods employed to assess retinal perfusion, supporting calls for standardisation of methodology.

Bibliometric analysis of the Vogt‒Koyanagi‒Harada disease literature

PURPOSE

As an autoimmune disease, Vogt‒Koyanagi‒Harada disease (VKHD) is a main type of uveitis in many countries and regions, significantly impacting patient vision. At present, information regarding VKHD is still limited, and further research is needed. We conducted a bibliometric analysis to characterize the overall status, current trends, and current focus of VKHD research.

METHOD

Literature published from 1975 to 2022 was obtained from the Web of Science core collection and analysed with the R-language packages Bibliometrix, VOSviewer, and CiteSpace software.

RESULTS

A total of 1050 papers on VKHD were retrieved from 261 journals, and 16,084 references were obtained from the papers in the original search. The average annual number of published articles was approximately 21.9, and the number of publications rapidly increased after 2004. The journal Ocular Immunology and Inflammation published the most papers on VKHD, while the American Journal of Ophthalmology has the highest citation frequency. The leading countries were Japan, China (PRC), and the United States of America (USA). Yang PZ from Chongqing Medical University was the most prolific and cited author. The most frequently cited study discussed revision of VKHD diagnostic criteria. An analysis of the highest frequency keywords showed that most research focused on the treatment, diagnosis, and pathogenesis of VKHD and its relationship with other related diseases. At present, the most urgent research direction is in the relationship between COVID-19 or COVID-19 vaccines and VKHD and the corresponding mechanisms underlying it.

CONCLUSION

Utilizing dynamic and visualization tools, bibliometrics provides a clear depiction of the research history, development trends, and research hotspots in VKHD It serves as a valuable tool for identifying research gaps and areas that necessitate further exploration. Our study revealed potential directions for future VKHD research, including investigating specific molecular mechanisms underlying the disease, exploring the clinical utility of optical coherence tomography angiography and other diagnostic techniques, and conducting clinical research on novel therapeutic drugs.

Classification of Vogt-Koyanagi-Harada disease using feature selection and classification based on wide-field swept-source optical coherence tomography angiography

Background: Vogt-Koyanagi-Harada (VKH) disease is a common and easily blinded uveitis entity, with choroid being the main involved site. Classification of VKH disease and its different stages is crucial because they differ in clinical manifestations and therapeutic interventions. Wide-field swept-source optical coherence tomography angiography (WSS-OCTA) provides the advantages of non-invasiveness, large-field-of-view, high resolution, and ease of measuring and calculating choroid, offering the potential feasibility of simplified VKH classification assessment based on WSS-OCTA. Methods: 15 healthy controls (HC), 13 acute-phase and 17 convalescent-phase VKH patients were included, undertaken WSS-OCTA examination with a scanning field of 15 × 9 mm². 20 WSS-OCTA parameters were then extracted from WSS-OCTA images. To classify HC and VKH patients in acute and convalescent phases, two 2-class VKH datasets (HC and VKH) and two 3-class VKH datasets (HC, acute-phase VKH, and convalescent-phase VKH) were established by the WSS-OCTA parameters alone or in combination with best-corrected visual acuity (logMAR BCVA) and intraocular pressure (IOP), respectively. A new feature selection and classification method that combines an equilibrium optimizer and a support vector machine (called SVM-EO) was adopted to select classification-sensitive parameters among the massive datasets and to achieve outstanding classification performance. The interpretability of the VKH classification models was demonstrated based on SHapley Additive exPlanations (SHAP). Results: Based on pure WSS-OCTA parameters, we achieved classification accuracies of 91.61% ± 12.17% and 86.69% ± 8.30% for 2- and 3-class VKH classification tasks. By combining the WSS-OCTA parameters and logMAR BCVA, we achieved better classification performance of 98.82% ± 2.63% and 96.16% ± 5.88%, respectively. Through SHAP analysis, we found that logMAR BCVA and vascular perfusion density (VPD) calculated from the whole field of view region in the choriocapillaris (whole FOV CC-VPD) were the most important features for VKH classification in our models. Conclusion: We achieved excellent VKH classification performance based on a non-invasive WSS-OCTA examination, which provides the possibility for future clinical VKH classification with high sensitivity and specificity.

Changes of Peripapillary Capillary Density in Patients with Vogt-Koyanagi-Harada Disease Evaluated by Optical Coherence Tomography Angiography

Objective

To analyze the longitudinal changes in peripapillary capillary density in patients with acute VKH with or without optic disc swelling by optical coherence tomography angiography (OCTA).

Methods

Retrospective case series. 44 patients (88 eyes) were enrolled and were divided into two groups according to presence/absence of optic disc swelling before treatment. Peripapillary capillary images were obtained by OCTA before and after 6 months of corticosteroid treatment and used to determine the radial peripapillary capillary (RPC), retinal plexus, and choriocapillaris vessel perfusion densities.

Results

Optic disc swelling was present in 12 patients (24 eyes) and absent in 32 patients (64 eyes). The sex distribution, age, intraocular pressure, and best-corrected visual acuity before and after treatment were not significantly different between the two groups (all P > 0.05). Compared to those in nonoptic disc swelling group, the percentages of decreased vessel perfusion densities after treatment in the supranasal (RPC, 100.00% vs. 75.00%), infranasal (RPC, 100.00% vs. 56.25%), infratemporal (RPC, 66.67% vs. 37.50%), and infranasal quadrants (retinal plexus, 83.33% vs. 56.25%) were significantly more in optic disc swelling group. The choriocapillaris vessel perfusion density increased after treatment in both groups.

Conclusions

Decreases in vessel perfusion densities of the RPC and retinal plexus after treatment in VKH patients with optic disc swelling were more common than in those without optic disc swelling. The choriocapillaris vessel perfusion density increased after treatment, regardless of the presence/absence of optic disc swelling.

Clinical and multimodal imaging characteristics of eyes with Vogt–Koyanagi–Harada disease: An Egyptian experience

BACKGROUND

Vogt-Koyanagi-Harada (VKH) disease is a vision-threatening inflammatory disorder that is challenging in diagnosis and management.

METHODS

Retrospective, record-based analysis of 54 eyes belonging to 27 adult patients that fulfilled the revised diagnostic criteria for VKH between January 2018 and January 2021. Demographic, clinical, and imaging data on presentation and during follow-up visits were collected for each patient. Available imaging studies included B-scan ultrasonography (B-scan US), spectral domain optical coherence tomography (OCT), fundus fluorescein angiography (FFA), and OCT angiography (OCT-A).

RESULTS

The female-to-male ratio was 2.38:1. Nineteen patients (70.37%) presented during an initial attack, while eight patients (29.63%) presented during recurrence. The most commonly presenting sign in the posterior segment was exudative retinal detachment (44 eyes, 81.48%). B-scan US was utilized in 4 eyes (7.41%), OCT was utilized in 48 eyes (88.89%) with the most common finding being subretinal fluid (43 eyes, 89.58%), FFA was performed in 39 eyes (72.22%) with the most common finding being punctate hyperfluorescence and late dye pooling (33 eyes, 84.62%), and OCT-A was performed in 30 eyes (55.56%), in which choriocapillaris flow deficit that correlated with disease activity was detectable in 25 eyes (83.33%). Improved visual acuity was noted in 85% of the eyes that were followed up.

CONCLUSION

Early diagnosis and treatment of VKH result in favorable visual outcome. Multimodal imaging, with the recent addition of OCT-A, provides complementary data that could serve in diagnosis and monitoring.

Microvasculature Features of Vogt-Koyanagi-Harada Disease Revealed by Widefield Swept-Source Optical Coherence Tomography Angiography

Background: Vogt-Koyanagi-Harada (VKH) disease is a multisystem autoimmune disorder which could induce bilateral panuveitis involving the posterior pole and peripheral fundus. Optical coherence tomography angiography (OCTA) provides several advantages over traditional fluorescence angiography for revealing pathological abnormalities of the retinal vasculature. Until recently, however, the OCTA field of view (FOV) was limited to 6 × 6 mm² scans.

Purpose: This study examined retinal vasculature and choriocapillaris abnormalities across multiple regions of the retina (15 × 9 mm² wide field, macular, peripapillary regions) among acute and convalescent VKH patients using a novel widefield swept-source OCTA (WSS-OCTA) device and assessed correlations between imaging features and best-corrected visual acuity (BCVA).

Methods: Twenty eyes of 13 VHK disease patients in the acute phase, 30 eyes of 17 patients in the convalescent phase, and 30 eyes of 15 healthy controls (HCs) were included in this study. Vascular length density (VLD) in superficial and deep vascular plexuses (SVP, DVP), vascular perfusion density (VPD) in SVP, DVP, and choriocapillaris (CC), and flow voids (FV) in CC were measured across multiple retinal regions via WSS-OCTA (PLEX Elite 9000, Carl Zeiss Meditec Inc., USA) using the 15 × 9 mm² scan pattern centered on the fovea and quantified by ImageJ.

Results: Compared to HCs, acute phase VKH patients exhibited significantly reduced SVP-VLD, SVP-VPD, and CC-VPD across multiple retinal regions (all p < 0.01). Notably, the FV area was more extensive in VKH patients, especially those in the acute phase (p < 0.01). These changes were reversed in the convalescent phase. Stepwise multiple linear regression analysis demonstrated that macular DVP-VLD and macular CC-VPD were the best predictive factors for BCVA in the acute and convalescent VKH groups.

Conclusion: The wider field of SS-OCAT provides more comprehensive and detailed images of the microvasculature abnormalities characterizing VKH disease. The quantifiable and layer-specific information from OCTA allows for the identification of sensitive and specific imaging markers for prognosis and treatment guidance, highlighting WSS-OCTA as a promising modality for the clinical management of VKH disease.

Decrease of choriocapillary vascular density measured by optical coherence tomography angiography in Vogt-Koyanagi-Harada disease

PURPOSE

Changes of choroidal circulation throughout the disease course of Vogt-Koyanagi-Harada (VKH) disease and the clinical significance remain unclear. Choriocapillary vascular density (CC VD) measured by optical coherence tomography angiography (OCTA) were compared in different disease stages of VKH and its correlation with other parameters was analyzed, aiming to explore their clinical relevance.

METHODS

This is a retrospective case series. One hundred and fourteen VKH patients and 47 normal controls (NCs) were included. Patients were grouped into the acute uveitic, convalescent, and chronic recurrent stages (only anterior recurrent cases included), and OCTA images were obtained from VKH patients in these stages. Best corrected visual acuity (BCVA), CC VD, and subfoveal choroidal thickness (SFCT) were recorded and compared.

RESULTS

CC VD in acute (58.26% ± 0.84%), convalescent (64.85% ± 0.33%), and chronic recurrent (62.78% ± 0.70%) stage of VKH patients were all significantly lower than that in NCs (66.37% ± 0.41%) (p < 0.001, p = 0.017, and p < 0.001, respectively). CC VD increased by 6.59% ± 0.91% with resolution of acute inflammation (p < 0.001) and decreased by 2.07% ± 0.74% during anterior uveitis relapse (p = 0.009). Patients with a positive history of anterior recurrence had lower CC VD (- 2.43% ± 0.75%, p = 0.003) in the convalescent stage than those without. CC VD was negatively correlated with logMAR BCVA in VKH (r =  - 0.261, p < 0.001).

CONCLUSION

CC VD was decreased in every stage of VKH. CC VD has the potential to reflect the status of uveitis and might be promising in monitoring the disease activity. OCTA is a convenient and straightforward tool to evaluate choroidal vascularity, and CC VD provides supplemental quantitative information of the choriocapillaris. Further studies are needed to explore the values of OCTA quantitative parameters in monitoring VKH progression, predicting visual prognosis, and guiding clinical decisions.