Melphalan toxicity following treatment of retinoblastoma identified by pattern electroretinogram.

To describe a patient with retinoblastoma and subsequent maculopathy unrelated to the tumor but related to intra-arterial melphalan documented by pattern electroretinography. Comprehensive ophthalmic evaluation, treatment with intra-arterial chemotherapy and subsequent follow-up including electroretinography to assess for macular dysfunction. A 3-year-old child was evaluated with electrophysiological investigations following treatment of unilateral Group D retinoblastoma with intra-arterial and intravitreal chemotherapy with melphalan. Pattern reversal visual evoked potential amplitude and P100 latency were normal in the left eye, but abnormal and delayed in the right eye. Pattern electroretinograms (pERGs) were abnormal on the right eye. Flash electroretinograms (fERGs) were normal on both eyes. Visual acuity dysfunction of 20/50 attributed to melphalan was seen on the right eye vs 20/40 on the left eye. Our case report demonstrates that pERG rather than fERG should be used to monitor baseline macular function and potential toxicity in children undergoing chemotherapy for retinoblastoma using skin electrodes when corneal electrodes are not tolerated. [ABSTRACT FROM AUTHOR]