Background: The aim of this work was to investigate the choroidal morphologic changes of Vogt-Koyanagi-Harada (VKH) disease in vivo using high-penetration optical coherence tomography (HP-OCT) with a long-wavelength light source (1,060 nm).
Methods: Fourteen patients with VKH disease were included in this study: 12 eyes of six patients with treatment-naive acute VKH in the first 6-12 months after diagnosis and 16 eyes of eight patients in the convalescent phase with a sunset glow fundus appearance. A prototype HP-OCT instrument was used to observe the deep choroid and sclera. The choroidal thickness was measured for more than 6 months in eyes with acute disease. The choroidal thickness in patients with a sunset glow fundus appearance for 2-9 years after the onset was also examined.
Results: In 12 eyes with acute VKH disease, the baseline choroidal thickness was significantly (p < 0.0001) greater than in controls. After treatment, the choroidal thickness decreased over time. However, the choroidal thickness increased markedly again in four eyes with recurrent disease. The mean thickness at 12 months was significantly less than the normal value (p < 0.0001). In 16 eyes with a sunset glow fundus appearance, the choroidal thickness was significantly (p < 0.0001) thinner compared to the controls.
Conclusions: Significant choroidal thickness changes underlie VKH disease, which progress over time. Objective measurement of the choroidal thickness using HP-OCT may be useful for longitudinal evaluation of VKH activity.