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Updated: Jun 13, 2026

Electroretinogram Recording for Infants and Children under Anesthesia to Achieve Optimal Dark Adaptation and International Standards
Published on: September 3, 2020
Photoreceptor responses of patients with congenital stationary night blindness
Abstract:
The present study examines the hypothesis that the electroretinogram (ERG) a-wave of patients with congenital stationary night blindness with myopia (CSNB) is solely cone mediated. The subjects include four patients with x-linked recessive inheritance, two patients with no family history, and thirteen age-matched normal subjects. Because normal subjects have relatively large b-waves (which can influence the measurement of the PIII component of the a-wave), the main response parameter studied was the slope of the a-wave. The results for the CSNB patients show that in the light adapted condition, the ratio of the responses to photopically balanced blue and red flashes was nearly unity; whereas, in the dark-adapted condition, the ratio was ~3 times greater. The ratios for the normal subjects were similar to those of the CSNB patients. These results lead to the conclusion that, in patients with CSNB, the ERG a-wave is not solely mediated by cones.
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