Large rod-like photopic signals in a possible new form of congenital night blindness.
A 10-year-old Persian girl has symptoms of congenital stationary night blindness and some drusen-like lesions in the region of the vascular arcades. Her electroretinogram shows no rod response to a weak stimulus, but a large (475 microV) slow scotopic response to a strong stimulus that is unchanged by photopic conditions (15 Fl background illumination). However, the response to flicker had the typical (smaller) amplitude of a cone signal. They may represent a new form of night blindness in which rod sensitivity is reduced so that there is no vision under dim conditions but rod function still persists under photopic conditions.
Marmor
M F
MF
Department of Ophthalmology, Stanford University School of Medicine, California.
D002648:Child; D003623:Dark Adaptation; D004594:Electrophysiology; D004596:Electroretinography; D005260:Female; D005425:Flicker Fusion; D006801:Humans; D009755:Night Blindness / Q000151:congenital* / Q000503:physiopathology; D010786:Photoreceptor Cells / Q000503:physiopathology*; D014794:Visual Fields