Magnetic resonance imaging in cavitary choroidal melanoma.

PURPOSE To report the development of a cavitary choroidal melanoma in a patient with nevus of Ota and describe its magnetic resonance imaging (MRI) features. PATIENT A 66-year-old man with right oculodermal melanocytosis and an ipsilateral choroidal cavitary melanoma was seen. Diagnosis was suspected on the clinical, ultrasonographic and MRI findings. RESULTS T1-weighted image showed a hyperintense solid mass containing hypointense cystic-like spaces delineated by hyperintense septa with respect to the vitreous. The reverse image was observed on T2-weighted images. A choroidal melanoma comprising epithelioid and spindle cells with multilocular cavities was documented histopathologically. CONCLUSIONS There may be an association between cavitary melanoma and nevus of Ota. Characteristic MRI findings could be helpful in the differential diagnosis of cavitary uveal melanoma.