Combined STA/MCA arterial bypass and gradual internal carotid artery occlusion for treatment of intracavernous and giant carotid artery aneurysms.

Intracavernous aneurysms are a clinical diagnostic and technical problem. The risk of a direct surgical clipping, whenever possible, is high. Carotid ligation remains the classical surgical treatment for inaccessible aneurysms. Internal carotid artery (ICA) ligation is more effective than common carotid artery (CCA) ligation but carries a higher risk of cerebral ischaemia. The performance of ipsilateral extra-intracranial arterial bypass (EIAB) helps to maintain blood flow in the cerebral hemisphere. It also may decrease the collateral flow formation through the circle of Willis with turbulence in the aneurysmal sac, thus enhancing thrombosis. A series of five cases is reported. The results are satisfactory except in one patient who died in the immediate postoperative period for malignant hemispheric edema, in spite of the patent bypass. The EIAB can reduce but not eliminate the risk of ischaemic complications related to ICA ligation.