Patterned macular dystrophy 3

Patterned macular dystrophy-3 (MDPT3), also called Martinique crinkled retinal pigment epitheliopathy, appears in the fourth or fifth decade of life and is characterized by a 'dry desert land' pattern of the fundus, involving the posterior pole initially and progressing from the temporal fovea to the periphery of the retina. Polypoid choroidal vasculopathy, choroidal neovascularization, or atrophic fibrous macular scarring can cause reduced visual acuity after age 50. Late-stage MDPT3 consists of a retinitis pigmentosa (RP; see 268000)-like phenotype due to death of retinal pigment epithelium (RPE) and photoreceptor cells. The dry desert land pattern observed on fundus examination corresponds to an irregular thickness of the Bruch membrane and the RPE, with a scalloped elevation ('crinkling') of the RPE observed on optical coherence tomography (OCT). Full-field electroretinography may be normal at preclinical and early stages of the dystrophy, but later cone and rod responses are severely reduced, consistent with progressive photoreceptor cell dysfunction and death at the final state (summary by Meunier et al., 2016). For a general phenotypic description and discussion of genetic heterogeneity of patterned macular dystrophy, see MDPT1 (169150). [from OMIM]