Multispectral image analysis in Vogt-Koyanagi-Harada disease

PurposeTo investigate fundus abnormalities in Vogt-Koyanagi-Harada (VKH) disease by a noninvasive tool, multispectral imaging (MSI). MethodsA total of 77 patients with VKH and 163 healthy controls were enrolled between January and April 2015. The MSI findings were evaluated in combination with fundus fluorescein angiography (FFA), optical coherent tomography (OCT) and fundus photography (FP). Additionally, we compared extent of exposure of choroidal blood vessels between patients with VKH and healthy controls to evaluate retinal transmission function. ResultsA number of features could be recognized by MSI which included (i) general depigmentation, (ii) clumping of pigment and (iii) macular depigmentation and/or hyperpigmentation. The percentages of these three abnormalities discovered by MSI in 52 inactive VKH patients with a duration of more than 2months in VKH were 67.3%, 75% and 84.6% respectively, which were all significantly higher than those detected by FFA, OCT or FP (p=0.0398, p<0.0001). Our study showed that MSI detected a higher percentages of these four abnormalities in patients with sunset glow fundus than in patients without this phenomenon (p=0.0492, p<0.0001). Additionally, at the same wavelength (590nm), exposure of choroidal blood vessels in inactive patients was stronger than in healthy controls and active patients (p<0.01, p<0.001). ConclusionOur results show that MSI is a sensitive noninvasive method to investigate the retinal pigment epithelium (RPE) in VKH disease. It is more likely to detect RPE abnormalities with MSI than when using FFA, OCT or FP. Retinal transmission function in inactive patients is stronger than that observed in active patients or healthy controls.