Hemorrhagic arachnoid cyst with third nerve paresis: CT and MR findings.

We report the CT and MR appearance of a nontraumatic hemorrhagic arachnoid cyst presenting with a third nerve paresis in a 37-year-old man. The cyst, located in the left suprasellar area, contained a fluid-blood level with stigmata of subacute hemorrhage on both CT and MR studies.