Effect of immunosuppressive therapy on ocular blood flow in initial-onset acute uveitis associated with Vogt-Koyanagi-Harada disease.

Purpose To investigate the effect of immunosuppressive therapy on blood flow and waveform parameters in the choroid and optic nerve head (ONH) in patients with initial-onset acute uveitis associated with Vogt-Koyanagi-Harada (VKH) disease. Methods In this prospective study, 18 patients (36 eyes) were studied. Laser speckle flowgraphy was performed at baseline and at 4 weeks, 8 weeks and 12 weeks after treatment. We analysed longitudinal changes in mean blur rate (MBR), blow-out time, blow-out score (BOS), acceleration time index (ATI), flow acceleration index (FAI), resistivity index (RI) and blood flow fluctuation. Results After immunosuppressive therapy, MBR, representing blood flow velocity, in the choroid and ONH significantly increased at each post-treatment time point compared to baseline values. Among the analysed pulse waveform parameters, BOS significantly increased, while RI and fluctuation significantly decreased. Increased BOS and decreased RI indicate decreased vascular resistance following treatment. There was a strong negative correlation between BOS and RI. Additionally, FAI increased in the choroid and ATI increased in ONH. Conclusions Immunosuppressive therapy in the acute uveitic phase of VKH disease improved inflammation-related impairment in choroidal and ONH blood flow.