Longitudinal Study of Visual Function in Vogt-Koyanagi-Harada Disease Using Full-Field Electroretinography

Abstract

To investigate the dynamic changes of full-field electroretinography (ffERG) and its relationship with structural changes in Vogt-Koyanagi-Harada (VKH) disease. Interventional case series. A total of 42 VKH patients (84 eyes) and 45 normal controls (90 eyes) were included in this study. All of the patients showed active uveitis and were referred to us within 2months after disease onset. Dynamic changes of retinal function were evaluated by ffERG before treatment and 2, 6, and 12months after treatment with systemic corticosteroids and cyclosporine. The relationship between ffERG data with structural changes as disclosed by B-scan ultrasonography, fundus fluorescein angiography (FFA), indocyanine green angiography, and optical coherence tomography were also evaluated. All investigated VKH patients showed a significantly decreased visual acuity and retinal structural changes before treatment. These changes significantly improved at 2months and no abnormalities were apparent at 6months following treatment. Full-field ERG showed significantly decreased amplitudes and prolonged implicit times for all dark-adapted (DA) and light-adapted ffERG responses before treatment. All these parameters, except the a-wave amplitude in the DA response, were improved at 2months and returned to the normal level at 12months. Our findings show that ffERG is a more sensitive method to detect improvement of visual function in VKH following treatment when compared to corrected distance visual acuity and the various imaging techniques to detect structural abnormalities in VKH.