This 80YO female was 20/400 in her right eye and counting fingers in her left eye due to probable adult-onset foveomacular vitelliform dystrophy (Adult Best’s). Funduscopically, there are bilateral round atrophic foveal lesions with peripheral drusen.
OCT of the right eye shows hyperreflective outer retinal material overlying a pocket of subretinal fluid. The underlying RPE is atrophic with bare Bruch’s membrane. OCT of the left eye shows complete outer retinal and RPE atrophy.
Learning Points:
Adult Best’s is associated with a mutation in the BEST1 gene, which encodes the bestrophin-1 protein.
Bestrophin-1, a calcium-activated chloride channel, is primarily found in the basolateral plasma membrane of the RPE. BEST1 mutations cause a variety of phenotypes, including autosomal recessive bestrophinopathy, best vitelliform macular dystrophy, and autosomal dominant vitreoretinochoroidopathy.
