Also known as Pavingstone Degeneration, it involves chorioretinal atrophy secondary to occlusion of a single lobule of choriocapillaris. This results in focal RPE and photoreceptor death, whereas the inner retina remains intact due to it’s blood supply from the unaffected central retinal artery.
Lesions are usually round to oval, and have scalloped, distinct margins. One can see the underlying large choroidal vessels & sclera. Often there is pigment hyperplasia at the edges of the lesion & pigment migration from atrophied RPE into sensory retina within the lesion. Usually, the overlying vitreous is unaffected and retinal detachments are unlikely to occur.
Lesions tend to be aligned in a row parallel to the ora, and are commonly found in inferior retina between the ora and the equator.
Prevalence is in approximately 1/3rd of adults over the age of 20 years, but increases with age and long axial lengths. There is no genetic link, symptoms or treatment necessary, but it is important to distinguish cobblestone degeneration from lattice degeneration, retinal holes and CHRPE.