Focal Choroidal Excavation in Retinal Dystrophies.

Aim: To investigate the presence of focal choroidal excavation (FCE) in patients with retinitis pigmentosa (RP), Stargardt's disease (STGD), and Best disease in the Indian population.
Methods: This retrospective consecutive case series included 309 eyes of 157 patients with RP (183 eyes), STGD (93 eyes), and Best disease (33 eyes) with good-quality, enhanced-depth spectral domain optical coherence tomography scans. Comprehensive ophthalmic examination data were collected. Characteristics of FCE, including location of FCE, type (conforming and non-conforming), maximal width, and depth, were noted.
Results: FCE was found in 2 out of 33 (6%) eyes with Best disease and no FCE was found in eyes with RP or STGD. The location of the FCE was extrafoveal in both cases. The first case had non-conforming FCE while the second case had the conforming type and the FCE occurred in association with choroidal neovascularization in the second case. The first case maintained good visual acuity of 20/20 over the entire period of follow-up (14 months), while the second case had a visual acuity of 20/200 at the last follow-up (three years) due to scarred choroidal neovascular membranes. The FCE showed no change in both eyes over the entire duration of follow-up.
Conclusion: Focal choroidal excavation was found in 6% of eyes with Best disease, which remained stable throughout follow up. Eyes with RP and STGD did not have any FCE. Further studies are required to determine the role of vitelliform material in FCE development in Best disease.