Melanoma-associated retinopathy

A 63-year-old Taiwanese man with a history of cutaneous melanoma presented with a rapid onset of bilateral shimmering light and blurred vision. A fundoscopic examination was normal. However, visual field examination indicated generalized depression in both eyes. Scotopic rod-specific electroretinography (ERG) was undetectable and scotopic maximal combined-cone and rod-specific ERG showed the characteristics of negative ERG (a normal a-wave and a diminished b-wave, with the b-wave smaller than the a-wave), indicating dysfunction of the bipolar cells. Melanoma-associated retinopathy (MAR) was suspected and a systemic work-up gave a diagnosis of metastatic melanoma. This case shows the typical presentation of MAR. Greater awareness of MAR in patients with unexplained visual loss may help to identify an occult focus of metastatic melanoma.