Functional and morphological variations of fundus flavimaculatus.

In order to investigate functional differences between fundus flavimaculatus and ophthalmoscopically similar diseases, we performed testing of spectral sensitivity, transient tritanopia, visual fields, fluorescein angiography, color vision, electrophysiological parameters, dark adaptation, cone flicker threshold during dark adaptation, and a thorough clinical investigation in five patients. Four had characteristic fundus flavimaculatus, while one patient turned out to have an atypical form. All five patients showed similar results in clinical investigations, electrophysiological data, and visual field tests. However psychophysical tests showed a number of differences in the single atypical patient. Although his ophthalmoscopic picture was not entirely typical of fundus flavimaculatus, only his psychophysical data could identify the patient as functionally distinct from the other four.