The use of spectral domain optical coherence tomography (SD-OCT) in the study of chronic serpiginous choroiditis was evaluated. Two patients with chronic serpiginous choroiditis were imaged using two prototype SD-OCT systems (6-microm axial resolution). Raster scans covering 6 x 6 X 2-mm regions of the retina were obtained, enabling the study of different retinal cross-sectional images. Thickness maps were obtained after segmentation of retinal layers, which could be compared with those on follow-up. SD-OCT allowed the visualization of the cross-sectional retinal architecture at different horizontal positions. Superimposition of SD-OCT generated reconstructed fundus images with fundus photographs provided accurate images registration. Segmentation of retinal layers provided thickness maps and higher-density improved visualization of photoreceptor layer, cysts, and atrophy, which was useful in following change in disease activity over time. The researchers concluded that SD-OCT is a useful tool to study disease morphology and follow-up of chronic serpiginous choroiditis.