What is Best's Disease

Best disease, also known as vitelliform macular dystrophy, is an hereditary form of progressive macular dystrophy first identified in 1905.

The macula is a small area of about 1mm in diameter in the centre of the retina, at the back of the eye where there is a concentration of cone cells. These cells are responsible for colour vision, sharp visual acuity and central vision. There are 6-7 million cone cells in the retina, the highest concentration of which is in the fovea, a tiny area in the centre of the macula.

Best disease is characterised clinically by the classical feature of a round or oval yellow subretinal macular deposit. The yellow material is gradually resorbed over time, leaving an area of RPE atrophy and often subretinal fibrosis. The flash electroretinogram (ERG) shows a normal response but the electrooculogram (EOG) shows a very reduced or absent light rise indicating that there is widespread dysfunction of the retinal pigment ephithelium (RPE). Also, histopathology of donated eyes from patients with Best disease has shown accumulation of lipofuscin throughout the RPE.

Best disease can be identified between 3 and 15 years of age.