Best Disease is also known as vitelliform macular dystrophy. This disease primarily affects the macular area and is degenerative in nature and generally begins at birth. The detection of symptoms does not readily appear and may take years, but the early lesions resembles the appearance of an egg yolk (round/oval shaped lesions and yellow in color), and the later stages resemble a scrambled egg appearance in the foveal area. With the degeneration, the patient will develop hemorrhage, abnormal blood vessel formation in the choroid, and scarring of the disc. This disease, in the late stages, is very difficult to distinguish from age related macular degeneration. Acute and permanent loss of central vision may occur in association with bleeding from new vessels. A macular hole may occasionally occur in some instances.
The patient should monitor vision daily with an Amsler grid for early detection. If someone with Best’s Disease has children, there is a 50% chance they will inherit the disease. Extensive testing with EOG and ERG should be performed on any suspected patient. The abnormal EOG with a normal ERG is consistent with the diagnosis of Best’s Disease.