Atypical presentations of Best's vitelliform macular degeneration: clinical findings in seven cases.

The clinical findings obtained in seven patients from four families with atypical vitelliform macular degeneration are described. Five patients had an onset of the disease in childhood and two patients, at the age of 45 years. Their visual acuity was mildly reduced (0.52 +/- 0.27). The fundus showed variable changes with single or multiple central or paracentral yellowish subretinal exudates and deposits, sometimes surrounded by scars. Both eyes were affected in all patients. The scotopic and photopic electroretinograms were normal in all cases. The electrooculogram (EOG) showed a significant reduction of the light rise in all affected eyes, and in five eyes a reduction in the dark trough could be observed. In three clinically unaffected first-order relatives with normal fundus appearance, the light rise of the EOG was reduced, thus identifying them as gene carriers. The clinical features of atypical vitelliform macular degeneration are discussed with respect to similar diseases that must be excluded and may give reason for misdiagnosis.