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

A Novel Risk Stratification-Based Immunomodulatory Treatment Strategy for Vogt-Koyanagi-Harada Disease

PURPOSE

To develop a more tailored immunomodulatory treatment (IMT) strategy based on a novel 2-arm risk stratification system in Vogt-Koyanagi-Harada (VKH) patients.

DESIGN

A retrospective clinical cohort study.

METHODS

Seventy-nine VKH patients in the acute stage were stratified into low- (n = 58) and high-risk (n = 21) groups based on their exposure to risk factors. They were treated with oral glucocorticoids (GCs) plus as-needed (PRN) or first-line IMT. Best corrected visual acuity (BCVA), sunset glow fundus (SGF) occurrence, relapse rate, and systemic adverse events were evaluated during follow-up.

RESULTS

Compared with the low-risk group, the high-risk group showed poorer BCVA at baseline (estimated difference 0.51, 95% CI 0.30-0.78; P < .001) and 6-month follow-up (estimated difference 0.08, 95% CI 0.00-0.08; P = .006), higher incidence of SGF at 12 months (52% vs 28%; RR 1.9, 95% CI 1.1-3.4; P = .040), and higher relapse rate at 6 months (24% vs 5%; RR 4.6, 95% CI 1.2-17.5; P = .028) and 12 months (52% vs 12%; RR 4.4, 95% CI 1.9-9.7; P < .001). In the low-risk cohort, no significant difference between the 2 IMT strategies was observed in primary outcomes. In the high-risk cohort, patients with the immediate IMT showed better BCVA (estimated difference -0.20, 95% CI -0.3 to -0.08; P = .007), lower incidence of SGF (27% vs 80%; RR 0.3, 95% CI 0.1-0.9; P = .030), and lower relapse rate (27% vs 80%; RR 0.3, 95% CI 0.1-0.9; P = .030) compared with the PRN regimen. Moreover, the immediate IMT regimen had a higher frequency of systemic adverse events than the PRN regimen (47% vs 7%; RR 7.1, 95% CI 2.5-20.4; P < .001).

CONCLUSIONS

High-risk stratification at baseline was associated with poor prognosis. The immediate IMT regimen was only beneficial for high-risk VKH patients regarding visual outcome, SGF, and relapse rate. This study suggests a potential need for a customized IMT strategy for VKH patients.

Lipid profile alterations in non-infectious uveitis: correlation with quantitative optical coherence tomography angiography parameters

BACKGROUND/AIMS

Lipid profiles have been changed in numerous chronic conditions. The impact of uveitis on lipid metabolism remains unclear.

METHODS

This is a cross-sectional study included 416 patients with non-infectious uveitis (NIU) and 416 healthy subjects. Standard techniques were used to measure total cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDLc), low-density lipoprotein-cholesterol (LDLc) levels. Quantitative optical coherence tomography angiography (OCTA) parameters were obtained from 500 eyes in each group. Correlation analysis examined the relationship between lipid profile and OCTA parameters.

RESULTS

Patients with NIU exhibited significantly elevated TC, TG and LDLc levels compared with controls (p=0.003; p<0.001; p<0.001, respectively). Subgroup analysis revealed that HDLc was significantly lower in Behçet's disease (p=0.024) compared with controls. Vascular density (VD) in the superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaris and optic disk were significantly decreased in NIU eyes (p<0.05, respectively) compared with controls. HDLc exhibited a significant negative correlation with VDs in the whole and parafovea SCP (r=-0.489, p=0.008; r=-0.480, p=0.0026, respectively), while LDLc showed a significant positive correlation with VDs in the whole and parafovea DCP in NIU patients (r=0.576, p=0.032; r=0.267, p=0.034, respectively).

CONCLUSIONS

The lipid profile is altered in NIU, and there are correlations between HDLc and LDLc levels and VD as measured by OCTA. Lipid profile analysis may offer valuable insights into evaluating vascular and metabolic aspects of NIU.

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.

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.

Quantitative Analysis of the Choroidal Vascularity in Eyes with Uveitis Using Optical Coherence Tomography Angiography: A Systematic Review

PURPOSE

The purpose of this systematic review is to identify techniques used for quantification of choriocapillaris (CC) flow in eyes with uveitis using optical coherence tomography angiography (OCTA), report reliability and level of correlation with techniques such as indocyanine green angiography (ICGA).

METHODS

A systematic search of several databases was done. The studies were analyzed for techniques of measurement, reliability, and correlation with other modalities. Risk of bias assessment was performed.

RESULTS

Thirteen studies were included. CC vessel density (7 studies) and flow deficit area (4 studies) were the most used indices. There was significant heterogeneity in the studies due to differences in the scan protocol, thresholding strategy, and analysis. Comparison with ICGA was performed by only one study, and reliability indices were reported by only two studies.

CONCLUSION

OCTA is a useful tool to measure the CC vascularity in eyes with uveitis. However, standardized acquisition and analysis protocols are needed.

Vogt-Koyanagi-Harada Disease and COVID

Vogt-Koyanagi-Harada (VKH) is a rare multisystem inflammatory disease affecting the eyes, ears, brain, skin, and hair. The Coronavirus Disease 2019 (COVID-19) is a new contagious infection that might trigger the onset of VKH disease, as previously proposed for other viruses. Moreover, after the mass vaccination against SARS-CoV-2 worldwide, cases of VKH disease associated with COVID-19 vaccination have been reported. We present an overview of VKH and a comprehensive literature revision of all the VKH cases described after COVID-19 infection and vaccination, adding our experience. No differences have been found considering epidemiology and clinical findings of the disease compared to those reported in the no-COVID era. All of the patients promptly responded to systemic and local corticosteroid therapy with a good final visual prognosis. Different possible pathogenetic mechanisms underlying the onset of VKH after COVID-19 vaccination are discussed, while the presence of the HLA DR4 antigen as a genetic predisposition for the onset of the disease after COVID-19 infection and vaccination is proposed. VKH disease is one of the most frequently reported uveitic entities after COVID-19 vaccination, but a good response to therapy should not discourage vaccination. Nevertheless, ophthalmologists should be alerted to the possibility of VKH occurrence or relapse after COVID-19 vaccination, especially in genetically predisposed subjects.

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.

Use of optical coherence tomography angiography in the uveitis clinic

As optical coherence tomography angiography is revolutionizing the ophthalmology world, the uveitis community is learning to understand where and how this new powerful imaging tool fits into the management of the panorama of ocular inflammations and infections. A non-invasive method of studying the retinal and choroidal vasculature, OCTA allows for the assessment of vessel density changes during active and inactive uveitis making it the natural imaging application of choice in uveitis clinical trials. However, these data and results are of limited utility to the ophthalmologists who are looking to apply OCTA in their everyday uveitis clinic. If employed strategically, OCTA can be a powerful tool for the uveitis specialist to evaluate iris involvement in viral uveitis; to assess the integrity of the vascular layers in the settings of white dot syndromes; to distinguish inflammatory choroidal neovascularization from outer retinal avascular inflammatory material; and to diagnose and follow infectious choroidal granulomas and satellite foci of chorioretinal inflammation without the need to administer dyes. The present review will analyze all the recent publications that apply OCTA in uveitis to offer the reader a guide on how to maximize the utility of this imaging modality in a clinical practice.

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.

Vogt-Koyanagi-Harada disease

PURPOSE OF REVIEW

Here, we provide an overview of Vogt-Koyanagi-Harada disease (VKH), including recent updates in our understanding of disease pathophysiology, classification and therapeutics.

RECENT FINDINGS

Advancements in bioinformatics, metabolomics and genomics investigations continue to illuminate VKH pathogenesis, and may provide insight into future therapeutic options. Multimodal imaging is indispensable in the initial evaluation of VKH, and is becoming increasingly important in understanding disease pathogenesis, as well as monitoring therapeutic response. Enhanced VKH classification criteria, released in 2021, provide standardized guidelines and terminology for clinical and research purposes.

SUMMARY

Modern research and imaging techniques continue to improve our understanding of VKH; more work is needed to further elucidate pathogenic mechanisms and establish optimal therapeutic recommendations.