The lesion evolves through several stages over many years, with increasing potential for adverse visual outcome. Lesions in this disease are restricted to the eye. No systemic associations exist. The RPE appears to have degenerative changes in some cases, and secondary loss of photoreceptor cells has been noted.
Visual acuity is good in the previtelliform stage.
It is the final stages of geographic RPE atrophy with possible development of choroidal neovascular membrane that is associated with further deterioration in acuity. These changes usually occur in individuals older than 40 years. Best disease is found in individuals of European, African, and Hispanic ancestry. No known gender predilection exists. The condition often is not detected until much later in the disease because visual acuity may remain good for many years.