Venous angioma of the optic chiasm.

A 30-year-old man presented with decreased vision in the right eye of three weeks' duration. Examination indicated a chiasmal syndrome and evidence of subarachnoid hemorrhage. CAT scan showed a large suprasellar mass. Surgical intervention confirmed the presence of a globular lesion filled with blood clots involving mainly the right side of the optic chiasm. Following removal of the clots, the chiasm regained its shape and anatomical landmarks. Biopsy of the mass demonstrated a venous angioma located within the optic chiasm as well as recent and old bleeding. Following surgery the patient did well and recovered vision in the right eye, though a left homonymous hemianopia persisted.