Imaging Serpiginous Choroidopathy With Spectral-Domain Optical Coherence Tomography

Abstract

Purpose: : Serpiginous choroiditis (SC) is a rare, usually bilateral, chronic, progressive, recurrent inflammation of the retinal pigment epithelium (RPE), choriocapillaris, and choroid of unknown etiology that has a wide spectrum of disease presentation. We evaluated the use of spectral-domain optical coherence tomography (SD-OCT) in SC.

Methods: : Both eyes of two patients with SC were imaged using two prototype SD-OCT systems (5 micron and 3 micron axial resolution respectively). Raster scans covering 6x6x2 mm volumes of the retina were obtained that could be accurately registered with the fundus photos and fluorescein angiograms. This was useful in point-to-point comparison on follow-up. Thickness maps were obtained from segmentation of the internal limiting membrane and RPE layers, which could be compared with those on follow-up.

Results: : SD-OCT allowed detailed visualization of retinal architecture, including the presence of retinal atrophy in the peripapillary region, with disruption of the photoreceptor layer and thinning of the RPE and mild cystic changes in the retina very close to the fovea. The high speed of SD-OCT allowed acquisition of high density images achieving 4096 A-scans in 0.16 seconds, resulting in improved visualization of subtle changes such as intraretinal cysts, the photoreceptor layer, retinal scarring as well as change in retinal fluid following steroid therapy in both cases. Superimposition of SD-OCT generated reconstructed fundus images with fundus photographs (using three or more blood vessels as landmarks) allowed for accurate image registration. Segmentation of retinal layers provided thickness maps which were useful in following change in disease activity with time.

Conclusions: : The SD-OCT features improved the ease of diagnosis and monitoring follow-up in SC. Enhanced visualization allowed for a more detailed view of the pathological retinal architecture and the macular thickness measurements allowed for a quantitative assessment from baseline to follow-up.

Keywords: retinochoroiditis • imaging/image analysis: clinical • retina