Malignant melanoma is one of the most common primary intraocular neoplasms. Recently, 99mTc radiolabelled (Fab')2 fragments of monoclonal antibody 225.28S raised against cutaneous melanomas have been used for imaging uveal melanomas. We report here a case where uptake of radiolabelled antibody was observed in a choroidal melanoma of the right eye and a benign choroidal naevus of the left.