Surgical Experience of Unbranched Dorsal Wall of the Internal Carotid Artery Aneurysms

Lee, Chang Sub; Park, Sang Keun; Shin, Hyung Shik; Kwon, Soon Chan; Kim, Sang Jin

Abstract

Most intracranial saccular aneurysms arise from the distal angle between a parent vessel and an arterial branch. We present three cases of saccular aneurysms arising from the unbranched-site of the dorsal wall of the intracranial internal carotid artery(ICA) total of 162 ICA aneurysms(1.9%). All three cases presented with sudden onset of headache and mental deterioration. Computerized tomography(CT) scans revealed typical pattern of aneurysmal subarachnoid hemorrhage. With transfemoral cerebral angiography(TFCA) dorsal wall aneurysms were easily detected except one case, which we missed small bulging at unusual site on initial TFCA. Second TFCA of this particular case a definite aneurysmal dilatation at dorsal wall of intracranial ICA. The operative findings disclosed darkish red entirely thin-walled aneurysms pointing to the sylvian cistern, attached to either temporal lobe or optic nerve. In two cases aneurysms were ruptured during neck dissection. The authors emphasize the pathogenesis and surgical points of this particular type of aneurysm with review of patient literatures.