Full-field electroretinography under general anesthesia in retinoblastoma

Abstract

Purpose: To investigate the electrical responses of the retina in retinoblastoma (RB), by recording full-field electroretinography (ERG) under general anesthesia. Methods: The ERG was recorded using Ephios hand-held portable ERG system, according to International Standards for Clinical Electrophysiology of Vision. Forty-eight eyes of 43 cases and 33 eyes of 33 controls were enrolled. The cases were classified based on international intraocular retinoblastoma classification (IIRC). Forty-eight eyes of cases were divided into 30 cases with active RB and 18 cases with regressed RB. Results: The amplitudes of a- and b-waves were decreased as compared to controls in all subgroups. The implicit times of all RB patients from group A to C differed statistically from controls (p value < 0.05) except for single-flash rod response. The ERG waveforms in group E eyes were non-recordable. The comparison of ERG parameters between active and regressed groups (IIRC groups A and B) was statistically insignificant. Single case follow-up of unilateral RB after systemic chemotherapy showed improvement in amplitudes compared to baseline parameters. Conclusions: Reduced amplitudes and delayed implicit times were noted in advanced disease. The ERG of RB cases did not follow any specific pattern of waveform. ERG appears to be a dynamic parameter to observe changes following treatment for RB. Although ERG is not a diagnostic test for RB, it can be used as a complementary test to assess the residual retinal function in RB eyes. © 2013 Springer-Verlag Berlin Heidelberg.