Interhemispheric subdural hematoma caused by a ruptured internal carotid artery aneurysm: Case report

BACKGROUND Interhemispheric subdural hematoma (ISH) usually occurs after he ad trauma; nontraumatic ISH is extremely rare. CASE DESCRIPTION The authors describe a 62-year-old male presenting with se vere headache and ptosis on the left side. Computed tomography (CT) and mag netic resonance imaging disclosed a hematoma in the interhemispheric subdur al space without subarachnoid hemorrhage. Cerebral angiography revealed an aneurysm arising from the left internal carotid-posterior communicating art ery (IC-PC) junction. The patient underwent emergency clipping of the aneur ysm and was discharged without neurological deficit. CONCLUSION Ruptured aneurysms resulting in ISH without subarachnoid hemorrh age have been reported in only a few cases; this is the second case to desc ribe the association of a ruptured IC-PC aneurysm with an ISH. The etiology of ISH formation due to ruptured aneurysms and the diagnosis are discussed . (C) 2000 by Elsevier Science Inc.