Objective: To demonstrate unique membranous structures seen on enhanced spectral domain optical coherence tomography (SD-OCT) images of eyes with acute Vogt-Koyanagi-Harada (VKH) disease.
Design: Retrospective, observational case series.
Participants: Twenty eyes of 10 consecutive patients diagnosed with acute VKH disease.
Methods: We reviewed fundus photographs, conventional OCT images, fluorescein angiograms (FA), and enhanced SD-OCT images, including serial sections through the macula, obtained at the initial visit and periodically after steroid treatment until complete resolution of serous retinal detachment.
Main outcome measures: Findings on enhanced SD-OCT imaging and FA in eyes with VKH disease.
Results: All 20 eyes had multifocal serous retinal detachment in the posterior fundus that appeared as multilobular dye pooling on late-phase FA. In 17 of the 20 eyes (85%), some areas of dye pooling corresponded to cystoid spaces on enhanced SD-OCT images and in 14 of the 20 (70%) eyes, there were areas of dye pooling and cystoid spaces in the fovea. The floors of the cystoid spaces consisted of a membranous structure of uniform thickness (mean thickness in the fovea of 14 eyes, 62.5+/-3.3 microm). The membranous structure, on SD-OCT, seemed to include a highly reflective line, which was continuous with the line representing the junction of the photoreceptor inner and outer segments (IS/OS) in attached areas of the retina. Intraretinal split was seen to overlie the abnormal IS/OS line in the vicinity of cystoid spaces involving the fovea in 9 of the 20 eyes (45%). During the course of steroid therapy, the membranous structure changed to a granular structure.
Conclusions: The membranous structure that can be seen in eyes with acute VKH disease seems to represent a portion of the outer segment layer that has become separated from the inner segment layer by cystoid spaces. We hypothesize that the membranous form of the outer segment is bound with the action of inflammatory products, such as fibrin, and this membranous structure changes to a granular structure as steroid therapy "dissolves" the fibrin holding the outer segments together.
Financial disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article.