Safety and efficacy of transgraft internal trapping after proximal internal carotid artery ligation with high-flow bypass.

Proximal internal carotid artery (ICA) ligation with high-flow bypass is an important vascular reconstructive technique for giant ICA aneurysms or skull base tumors involving the ICA to control intraoperative bleeding. Retrograde or collateral blood flow occasionally remains postoperatively and requires complete internal trapping. Although transgraft internal trapping is one of the options, there are few reports on transgraft treatment. The purpose of this study was to report our experience of transgraft internal trapping and evaluate the safety and efficacy of this procedure. We retrospectively selected patients who underwent transgraft internal trapping after proximal ICA ligation with high-flow bypass between January 2012 and June 2020. We encountered five cases of this procedure (one aneurysm case and four tumor cases). The median duration between the bypass and transgraft internal trapping was 12 days. In four out of five cases, a guiding catheter could be placed in the graft. No disruption of the anastomosis was observed. Transgraft internal trapping was achieved in all five cases with detachable coils. All treatments could be completed safely without any adverse events, including ischemic and hemorrhagic complications. Transgraft internal trapping after proximal ICA ligation with high-flow bypass may be an option for preventing residual retrograde blood flow.