[EOG in adult vitelliform macular degeneration, butterfly-shaped pattern dystrophy and Best 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-shaped dystrophy.

Patients And Methods: The records of 49 patients (98 eyes) in whom foveomacular dystrophy had been diagnosed by ophthalmoscopy or by fundus photographs and fluorescein angiography were retrospectively 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 and Täumer. The results were compared to those in Best's disease and butterfly-shaped dystrophy.

Results: In foveomacular dystrophy all mean EOG values were within normal ranges. There was no difference between the various stages of the disease. In Best's disease only the dark-adapted steady-state potential was in the normal range. The amplitude and the implicit time of the light peak were significantly different from those in patients with foveomacular dystrophy (P < 0.05 ANOVA). In butterfly-shaped dystrophy all the EOG parameters were normal. The ratio of the light peak to steady-state potential was significantly lower in foveomacular dystrophy than in butterfly-shaped dystrophy.

Conclusion: In foveomacular dystrophy the mean values of the EOG were normal. Despite the morphological similarity we found more pronounced electrophysiological differences from Best's disease than from butterfly-shaped dystrophy.