Does universal bypass before carotid artery occlusion obviate the need for balloon test occlusion: Personal experience with extracranial-Intracranial bypass in 23 patients

Aim: Carotid artery ligation carries a potential risk of ischemic complications even in patients with good collaterals and adequate cross-circulation. Preoperative assessment through balloon test occlusion (BTO) is technically challenging and not feasible in all patients. We analyze our experience with universal bypass without performing detailed cerebrovascular reserve (CVR) studies in 23 patients before carotid artery ligation. Patients and Methods: This was a retrospective analysis of the case records of 23 patients who underwent cervical carotid artery ligation for various indications since January 2009. Results: The study included 21 patients with cavernous carotid aneurysms, one patient with a large fusiform petrous carotid aneurysm, and one patient with recurrent glomus jugulare encasing the cervical internal carotid artery. The initial 12 patients underwent preoperative BTO with hypotensive challenge. All patients underwent a bypass procedure followed by carotid artery ligation irrespective of the BTO findings. Patients who successfully completed a BTO underwent a low-flow superficial temporal artery to middle cerebral artery bypass. A high-flow extracranial-intracranial bypass using a saphenous vein graft from external carotid artery to middle cerebral artery was done in all patients who either failed the BTO or did not undergo BTO. We had two operative mortalities and one poor outcome. All the other patients had a good recovery with a Glasgow outcome score of 5 at the last follow-up. Graft patency rates were 81.1% in both the low-flow and high-flow groups. Conclusion: Universal high-flow bypass is safe, effective, and should be preferred in all patients before carotid artery ligation. It obviates the need for detailed CVR assessment, especially in centers with limited resources.