Contralateral Epidural Hematoma after Aneurysmal Clipping

Case Report

Abstract

Cerebral angiograms of a 48-year-old woman with subarachnoid hemorrhage revealed an aneurysm on the anterior communicating artery. The aneurysm was clipped 38 days after onset via the pterional approach, with the patient in the supine position. During surgery, 900 ml of mannitol was administered and her blood pressure and body temperature were normal. However, 1 hour postoperatively, disturbance of consciousness and right hemiparesis were noted. Computed tomographic scans obtained 30 minutes later showed a large epidural hematoma in the left frontoparietal region, contralateral to the craniotomy site. Emergency evacuation of the hematoma was performed. The patient's postoperative course was uneventful and she had fully recovered at the time of discharge.
Postoperative epidural hematomas distant to the operative site are often seen after ventricular drainage, shunting, and suboccipital craniectomy and are attributed to intensive internal decompression. However, a review of the literature yielded only four other cases of contralateral epidural hematoma following aneurysmal clipping. Among the five reported cases (the authors' case included), surgery was performed within 16 to 47 days of the onset of subarachnoid hemorrhage. The interval between surgery and detection of the hematoma ranged from 1.5 to 4 hours in four cases. In three cases the hematoma was in the contralateral frontal region.