Mydriasis as a falsely localizing sign in epidural hematoma: A case report

Mydriasis in a trauma patient is a neurologic emergency. Pupil dilation can be the result of uncal herniation causing compression of the third cranial nerve and subsequent brain stem compromise. However, not all patients with nonreactive, enlarged pupils have uncal herniation. We report the case of a 33-year-old epileptic man who developed a fixed, dilated contralateral pupil with a left temporoparietal epidural hematoma. He had a Glasgow Coma Score of 4 (eye opening, 1; motor, 2; and verbal, 1). Although a unilateral fixed dilated pupil commonly occurs ipsilateral to a supratentorial mass, it can also be a "false localizing sign." Preoperative computerized tomography scanning is necessary to diagnose the intracranial pathology. © 2007 Lippincott Williams & Wilkins, Inc.