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Updated: Aug 12, 2026

A Murine Model of Ischemic Retinal Injury Induced by Transient Bilateral Common Carotid Artery Occlusion
Published on: November 12, 2020
Predominant loss of the photopic negative response in central retinal artery occlusion
Shigeki Machida1, Yasutaka Gotoh, Michiko Tanaka
1Department of Ophthalmology, Iwate Medical University, School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan. smachid@clubAA.com
Purpose:
To determine how the photopic negative response (PhNR) is affected in central retinal artery occlusion (CRAO).
Design:
Observational case series.
Methods:
Seven patients with unilateral CRAO were included. Full-field scotopic and photopic electroretinograms (ERGs) including the PhNR were recorded. Each ERG amplitude in the affected eye was expressed as a percentage of amplitude of the corresponding wave in the unaffected eye.
Results:
Mean of the PhNR amplitude was reduced to 12.3 +/- 11.7% of that of unaffected eyes whereas the cone b-wave amplitude was attenuated to only 73.4 +/- 30.4%. This reduction of the PhNR amplitude was more significant than that of other waves including the rod b-wave, maximum a-wave and b-wave, cone a-wave and b-wave, and 30 Hz flicker ERG (P <.005).
Conclusions:
The PhNR was severely affected in CRAO despite relative preservation of the cone b-wave, implicating massive loss of ganglion cells and their axons.
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