Chorioretinal Degenerations

Abstract

The group of chorioretinal degenerations that are considered benign and therefore not indicated for prophylactic laser treatment includes peripheral chorioretinal atrophy of the retinal pigment epithelium, congenital hypertrophy of the retinal pigment epithelium, honeycomb degeneration and peripheral retinal drusen.

Peripheral chorioretinal atrophy of the retinal pigment epithelium is characterized by atrophic changes in the outer retinal layers, pigment epithelium, and choriocapillaris, with no changes in the vitreous. It may be of either multiple (paving-stone degeneration) or individual distribution.

Congenital hypertrophy of the retinal pigment epithelium (CHRPE) is a result of pigment redistribution and is usually not associated with vitreous traction, changes in the vitreoretinal interface, or risk of retinal detachment. However, there have been reports of retinal tears in 11.9 % of cases of advanced CHRPE. Unifocal CHRPE can be surrounded by a hypopigmented halo, and multifocal CHRPE appears as grouped pigmented spots resembling bear tracks.

Honeycomb degeneration is an age-related retinal degeneration characterized by hyperpigmented net extending up to the equator.

Peripheral retinal drusen are extracellular deposits of proteins and fatty unstructured material resulting from the degeneration of pigment epithelial cells, which accumulate metabolic waste products and excrete them in the inner layers of Bruch’s membrane. Retinal drusen have different forms and sizes but are most commonly small, round- or dome-shaped, and are clearly outlined in front of the healthy retina.