Nietypowa dystrofia siatkówki z nadnormalnym elektroretinogramem
Atypical Retinal Dystrophy with Supernormal Electroretinogram
Dariusz Łąk, Wojciech Lubiński
Katedra i Klinika Okulistyki Pomorskiej Akademii Medycznej w Szczecinie Kierownik: prof. dr hab. med. Danuta Karczewicz
Summary: Purpose: To present a literature review of the atypical cone-rod dystrophy with supernormal electroretinogram and a case of this dystrophy diagnosed in our electrophysiological laboratory.
Material and methods: A routine ophthalmologic examination, fundus photographs, color vision testing, fluorescein angiography, white-on white static perimetry and flash electroretinography (ERG) were performed.
Results: The diagnosis of the atypical retinal dystrophy with supernormal electroretinogram was established based on the patient's medical history and characteristic ERG abnormalities i. e.: in the dark adapted state – reduced amplitude and significantly increased latency of the b-wave after single, white flash stimulation (24dB), supernormal b-wave after single, white flash stimulation (0 dB); in the light adapted state – reduced amplitude and increased latency of the b-wave after single, white flash (0 dB) and flicker stimulations (30 Hz – 0 dB).
Conclusion: In opposite to many retinal degenerations where the differential diagnosis may be performed based on the clinical findings alone, flash ERG is necessary for diagnosis of this atypical cone-rod dystrophy.