ERG monitoring of retinal function during systemic chemotherapy for retinoblastoma.
Overview
abstract
BACKGROUND/AIMS: We have previously introduced electroretinography (ERG) as a proxy for visual function to monitor for retinal toxicity due to intra-arterial chemotherapy for retinoblastoma in young children. In this paper, we report ERG results for patients with retinoblastoma receiving initial treatment with systemic chemotherapy. METHODS: Inclusion criteria were patients presenting with retinoblastoma at <3 months of age or <6.0 kg in weight, with large tumours not amenable to local laser treatment, cryotherapy or plaque brachytherapy. Patients received intravenous carboplatin 18.7 mg/kg every 3-5 weeks, contingent on recovery of blood counts, until they had grown sufficiently to receive intra-arterial chemotherapy. ERG was performed during examination under anaesthesia at monthly intervals, using contact lens electrodes and a hand-held ganzfeld stimulator. 30-Hertz flicker responses are reported. RESULTS: Four patients were treated for bilateral retinoblastoma. All eyes responded well to systemic chemotherapy. 30-Hertz flicker ERGs improved during treatment in all eyes, significantly in six of eight eyes, and at least in one eye of each patient. CONCLUSION: Effective systemic chemotherapy for retinoblastoma in children who are too small for intra-arterial chemotherapy is compatible with significant increases in ERG amplitudes, even in eyes presenting with extinguished ERGs. ERG signals may increase independent of resolution of retinal detachment.
