[Clinicopathological findings of melanocytomas on the optic disc (author's transl)].

Two cases of melanocytoma on the optic disc were reported, one of which was a clinically typical case and the other one showed atypical symptoms. The atypical case was diagnosed as a malignant melanoma because of increasing pigmentation, progressive visual disturbance, and the leakage in the fluorescein angiogram and the eye was, therefore, removed. Histologically, however, a melanocytoma on the optic disc was diagnosed. The cause of the clinical atypical symptom and the origin of the melanocytoma cells have been discussed histopathologically.