CT Findings of Rupture of Pre-existing Cerebral Aneurysm in Blunt Head Trauma

Park, Heu Jung; Kim, Gab Teog

Abstract

PURPOSE: Rupture of pre-existing cerebral aneurysms has been reported as a cause of traumatic subarachnoid hemorrhage (TSAH). SAH due to rupture of pre-existing cerebral aneurysm is an important differential diagnosis in TSAH. Our study was aimed to assess whether a rupture in a pre-existing cerebral aneurysm could be predicted on the basis of the quantity and distribution pattern of hemorrhage on the initial computed tomography (CT).
METHODS
197 patients with TSAH were retrospectively studied between the years 2003 and 2008. We examined the age and sex of patients, mechanisms of injury, consciousness level at admission, and CT parameters including the distribution and quantity of SAH, localized blood clot, intraventricular hemorrhage, or hemorrhagic contusion and extra-axial hematoma. We compared the patients with nonaneurysmal TSAH to the patients with aneurysmal TSAH.
RESULTS
22(11.2%) patients with TSAH harbored pre-existing cerebral saccular aneurysms. The aneurysms were found in the patients with diffuse or anteriorly located blood in the basal cisterns(40.6%), unilateral sylvian fissure (16.7%), and anterior interhemispheric fissure(18.2%). But the aneurysm was not found in all patients with perimesencephalic hemorrhage, bilateral sylvian fissures, and convexities. TSAH with localized clot in the anterior interhemispheric or sylvian fissure (OR=5.924, p=0.005), or SAH completely filling any cistern or fissure (OR=3.148, p=0.034) was significantly associated with rupture of pre-existing cerebral aneurysm in logistic regression analysis.
CONCLUSION
SAH in the basal cisterns extended into bilateral sylvian fissures and anterior interhemispheric fissure, and SAH in the unilteral sylvian fissure on initial CT could be predicted rupture of pre-existing cerebral aneurysm.