EOG IN ADULT-ONSET VITELLIFORM MACULAR DY STROPHY, BUTTERFLY-SHAPED PATTERN DYSTROPHY AND BESTS-DISEASE

Objectives: We evaluated the EOG in the various stages of foveomacular dystrophy (also called adult-onset vitelliform macular dystrophy) and compared these findings to those in Best's disease and butterfly-shap ed dystrophy. Patients and methods: The records of 49 patients (98 eye s) in whom foveomacular dystrophy had been diagnosed by ophthalmoscopy or by fundus photographs and fluorescein angiography were retrospecti vely reviewed. Fifty-seven eyes were followed up (range 1.1-20 years, mean 10.4 years). EOG was elicited according to the method of Rohde an d Taumer. The results were compared to those in Best's disease and but terfly-shaped dystrophy. Results:ln foveomacular dystrophy all mean EO G values were within normal ranges. There was no difference between th e various stages of the disease. In Best's disease only the dark-adapt ed steady-state potential was in the normal range. The amplitude and t he implicit time of the light peak were significantly different from t hose in patients with foveomacular dystrophy (P<0.05 ANOVA). In butter fly-shaped dystrophy all the EOG parameters were normal. The ratio of the light peak to steady-state potential was significantly lower in fo veomacular dystrophy than in butterfly-shaped dystrophy. Conclusion: I n foveomacular dystrophy the mean values of the EOG were normal. Despi te the morphological similarity we found more pronounced electrophysio logical differences from Best's disease than from butterfly-shaped dys trophy.