Preservation of Anterior Choroidal Artery Blood Flow During Trapping of the Internal Carotid Artery for a Ruptured Blood Blister-Like Aneurysm with High-Flow Bypass

Abstract

The ideal surgery for a blood blister-like aneurysm (BBA) in the internal carotid artery (ICA) involves complete termination of blood flow into the BBA by trapping of the ICA at sites both proximal and distal to the BBA. In the present report, we describe a clipping method with ICA trapping for prevention of anterior choroidal artery ischemia, a major problem in ICA trapping with reconstruction surgery using external carotid artery-middle cerebral artery high-flow bypass (HFB). The data from patients with a ruptured BBA treated by the combination of ICA trapping and blood flow reconstruction from 2008 to 2018 were retrospectively evaluated. Fifteen patients had been treated with the combination surgery. Clip placement for ICA trapping depended on the relationship between the distal neck of the BBA and the posterior communicating artery. In the case of the BBA distal neck located at the same level or distal to the posterior communicating artery, oblique placement of a distal clip to the ICA was mandatory to maintain blood flow of the anterior choroidal artery. No patients developed recurrence of the BBA after trapping. The outcomes were assessed using the modified Rankin scale score, with a score of 0 or 1 in 12 of the 15 patients (80%). A complete shutdown of blood flow to the BBA by ICA trapping is essential for the permanent prevention of BBA recurrence. In cases of a BBA distal neck located distal to the posterior communicating artery, the oblique clipping technique applied to the ICA is useful to prevent ischemic complications of the anterior choroidal artery.