Vitelline Macular Dystrophy

Abstract

Abstract Vitelline macular dystrophy (also known as Best disease) is a progressive, chronic disease of the macula (central retina) at the back of the eye. Best disease is characterised by the development of a lesion in the retinal pigment epithelium and emerging as one of the leading causes of blindness in both juvenile and adult cases. This disease has an autosomal dominant pattern of inheritance with varied penetrance and expressivity. Diagnosis of this disease is delayed due to the fact that the individual may be asymptomatic for several years and the disease can be identified only after visual acuity reduces, during which the disease could have progressed to later stages. Mutations observed in the BEST1 and PRPH2 genes are involved in development of the disease. In this article, a review of the history, genetics and pathophysiology, diagnosis and treatment is outlined for further understanding of this disease. Key Concepts: Macular dystrophy is a rare, genetic condition of the eye, wherein the macula, which is the central part of the retina, is damaged due to successive buildup of eye pigments within the epithelial cells of the retina. There are two main types of this disease: Best disease, which is seen in juvenile cases, and adult‐onset macular dystrophy. Best disease is also known as early‐onset or juvenile vitelliform macular dystrophy. It is an autosomal dominant disorder characterised by the accumulation of specific eye pigment material in the subretinal space, which leads to the formation of a lesion on the macula. Adult‐onset vitelliform macular dystrophy is a disease of the retina wherein central vision loss occurs in the fourth or fifth decade of life. It is an autosomal dominant disorder. It is a dystrophy of the retinal pigment epithelium causing lesions on the macula. VMD2 gene, also known as the BEST1 gene, codes for a protein called bestrophin. This protein functions as a chloride ion channel in the eye and its dysfunction leads to buildup of pigments and eventual loss of central vision. PRPH2 gene codes for a protein called peripherin. This protein is essential for light sensing in the retina. Mutations in this gene lead to central vision loss.