Abstract
A male patient suffering from cone dystrophy was followed over 9 years. In addition to the typical clinical and electrophysiologic signs, supernormal b-waves were found in the dark-adapated electroretinogram. Our case is compared with 12 similar patients described in the literature. Our patient differed from the other patients in the following aspects: he was male and had a congenital stationary disease with a small pigment epithelial scar in the left eye only and no other fundus changes up to the age of 22 years. He did not complain of night blindness. The dark-adapted electroretinogram of our patient showed a normal b-wave threshold with increased b-wave amplitudes and markedly prolonged b-wave latencies and implicit times. This combination of signs has not been reported to date in any other patient and points towards a postreceptoral defect of the interneuronal connection.
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Foerster, M.H., Kellner, U. & Wessing, A. Cone dystrophy and supernormal dark-adapted b-waves in the electroretinogram. Graefe's Arch Clin Exp Ophthalmol 228, 116–119 (1990). https://doi.org/10.1007/BF00935718
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DOI: https://doi.org/10.1007/BF00935718