Aim To evaluate the choroidal thickness (CT) in patients with long-standing Vogt–Koyanagi–Harada (VKH) disease using enhanced depth imaging optical coherence tomography (EDI-OCT).
Methods A prospective case–control study developed at a tertiary centre at São Paulo, Brazil. EDI-OCT images were obtained in 16 patients (30 eyes) with VKH disease who had had the disease for more than 6 months since disease onset, and in 17 normal individuals controlled by age (32 eyes). Comprehensive ophthalmic examination and EDI-OCT evaluation were performed. CT was measured at the fovea and at 1000 µm intervals from the foveal centre in both temporal and nasal directions. CT was correlated with disease duration, clinical disease activity and fundus-based disease severity.
Results Mean subfoveal CT was 333 µm (±85.8) in controls and 250.7 µm (±93.3) in VKH patients (p=0.002). The choroid was significantly thinner in patients when compared to controls in all but one nasal point. In patients, the CT measurements at the foveal centre presented a negative correlation with disease duration (p<0.001). No significant difference in CT measurements was observed between eyes with and without clinical inflammation (p=0.42). There was a trend towards more severe fundus changes being associated with a thinner choroid (p=0.28).
Conclusions Patients with VKH and long-standing disease had thinner choroids when compared to controls. Progressive choroidal thinning related to disease duration was observed at the macula of these patients. Whether this finding is part of the natural history of the disease or the result of a clinically undetected choroidal inflammation remains to be determined.