ANEURYSM OF SUPERIOR BRANCH OF ANTERIOR CHOROIDAL ARTERY MIMICKING CAROTID BIFURCATION ANEURYSM - CASE-REPORT

Aneurysm of the superior branch of anterior choroidal artery is very r are. We report this rare case with unique angiographic findings mimick ing an internal carotid bifurcation aneurysm. A 35-year-old woman was admitted to our hospital because of severe headache. Lumbar puncture d isclosed numerous red blood cells. Computed tomography revealed an enh anced circular area in the left basal cistern with moderate hydrocepha lus. Cerebral angiography showed a saccular aneurysm near the left int ernal carotid bifurcation. During operation, the aneurysm was not foun d at thr internal carotid bifurcation, but located deeper budding from the superior branch of the anterior choroidal artery, The aneurysm wa s successfully clipped. The postoperative course was favourable withou t any neurological deficit. The postoperative angiogram showed that th e aneurysm was clipped well with preservation of the main trunk of the anterior choroidal artery. Computed tomography of the brain did not s how any infarction area, 3 months after the surgery. The uniqueness of this case is the favourable outcome after sacrificing the superior br anch of the anterior choroidal artery, The role of collaterals of the anterior perforating substance is emphasized.