Unusual computed tomographic findings in a case of arachnoid cyst in the middle cranial fossa.

A rare case is reported of arachnoid cyst in the middle cranial fossa associated with intracystic hemorrhage and subdural hematoma. The preoperative computed tomography scans showed no difference in density among the cyst, the hematoma, and the brain parenchyma. The serial computed tomography scans after the accident were the most helpful in making the correct diagnosis.