Abstract
Purpose: :
To investigate the correlation of the scotopic and photopic components of the electroretinograms (ERGs) with the degree of circulation disturbances in central retinal artery occlusion (CRAO).
Methods: :
Sixteen eyes of 16 patients with CRAO were involved. The circulation disturbance in eyes with CRAO was graded as mild (Group I) in which an arm-to-retina transmission time <30 seconds, moderate (Group 2) in which an arm-to-retina transmission time >30 seconds, and severe (Group 3) in which retinal as well as choroidal circulations were disturbed. Scotopic and photopic ERG components in eyes with CRAO were compared to those in healthy fellow eyes with respect to the circulation disturbance grade.
Results: :
The scotopic and photopic b-wave was significantly reduced in the Groups 2 and 3, while the amplitudes of the photopic negative response (PhNR) corresponding component of the photopic ERGs were significantly reduced in all three groups. The amplitudes of each ERG component except the a-wave of the mixed rod and cone ERG were negatively correlated with the severity of the ocular circulation, i.e., the amplitudes decreased as the severity of the ocular circulation disturbances increased.
Conclusions: :
The PhNR corresponding component was reduced even in the group 1 with minimal circulatory disturbance and thus may be a good functional indicator.
Keywords: vascular occlusion/vascular occlusive disease • electrophysiology: clinical • retina