A normal electrooculogram in a patient with a typical vitelliform macular lesion.

The diagnosis of vitelliform macular dystrophy can be made from fundus examination alone when the classical egg-yolk lesion is intact. After the lesion has scrambled, however, other information is needed to be certain of the diagnosis. The electrooculogram (EOG) has been reported abnormal in vitelliform macular dystrophy and has been called "an indispensable diagnostic element." This paper, however, presents a patient with the classical sunny-side-up egg-yolk lesion of vitelliform macular dystrophy and an entirely normal EOG and slightly abnormal electroretinogram (ERG). To our knowledge, this is the first report of a patient with these findings.