# Analysis of the Retinal Microcirculation in Chinese Patients With Vogt–Koyanagi–Harada Disease by Optical Coherence Tomography Angiography

## TL;DR

This study uses OCTA to analyze retinal blood flow in Chinese patients with VKH disease, showing that treatment improves blood flow and vision.

## Contribution

The study is the first to describe retinal microcirculation changes in Chinese VKH patients using OCTA and their response to treatment.

## Key findings

- VKH patients showed reduced vessel and perfusion density before treatment, which normalized after 2 months.
- Visual acuity improved significantly with treatment and correlated with retinal blood flow parameters.
- FAZ metrics remained stable and similar to controls throughout the study.

## Abstract

The dynamic changes of retinal microcirculation in Chinese Vogt–Koyanagi–Harada (VKH) patients have not yet been described. This study aimed to explore changes in retinal microcirculation among Chinese with VKH disease using optical coherence tomography angiography (OCTA) technology to determine whether patient outcomes improve due to therapeutic interventions.

The study included 43 VKH patients and 43 normal controls. Vessel density (VD), perfusion density (PD), and the foveal avascular zone (FAZ) area, perimeter, and circularity were measured by OCTA. Clinical and demographic characteristics of VKH patients and visual acuity changes were recorded. All patients were treated with prednisone in combination with cyclosporine.

Before treatment, VD of the parafoveal and full area, PD of the parafoveal area, and visual acuity were significantly decreased in VKH patients compared to controls. These parameters increased significantly to normal values after 2 months of treatment and maintained a normal level thereafter. VD of the foveal area, PD of the foveal and full area, and FAZ area, perimeter, and circularity did not differ from those of normal eyes and showed no significant changes following treatment. A negative correlation was found between visual acuity and PD of the parafoveal and full area and FAZ area and circularity.

Decreased retinal VD and PD were observed in Chinese VKH patients, which returned to normal values following treatment. OCTA analysis may be a useful method to follow the response of VKH patients to treatment.

OCTA can objectively evaluate the retinal microcirculation and is an effective technology to track the response of VKH patients to treatment.