Willis covered stent for complex internal carotid aneurysms

Abstract

Objective To investigate the safety and efficacy of the Willis covered stent system for the treatment of complex internal carotid aneurysms. Methods Eight patients with complex internal carotid aneurysm treated with Willis covered stent system at the Department of Neurosurgery, Nanfang Hospital, Southern Medical University from November 2013 to May 2015 were analyzed retrospectively. Among them, 3 patients had internal carotid artery blood blister like aneurysms, 2 had paraclinoid segment aneurysms, and 3 had cavernous segment aneurysms (1 traumatic pseudoaneurysm, 1 iatrogenic pseudoaneurysm, and 1 giant aneurysm). According to the intraoperative condition of the paren artery, the guiding catheters were placed as high as possible (near the cavernous segment) to provide adequate support. After the covered stents were implanted.the balloon were inflated to release the stent and the aneurysm were eliminated at the same time. Results Eight patients with complex internal carotid aneurysm (8 aneurysms) were implanted 8 covered stents, 7 of them were successfully released in the parent arteries. Angiography immediately after stenting in 5 patients showed that the lesions disappeared completely and the parent arteries were patent; After 1 stent was implanted, 1 patient with recurrent giant aneurysm at the cavernous segment after stent-assisted embolization, a small amount of contrast agent leaked into the aneurysm (endoleak). The stent system in place was difficult in 1 patent with blood blister like aneurysm because of his internal carotid artery tortuosity. Iatrogenic internal carotid cavernous fistula occurred during the operation. Bypass and occlusion of the parent artery was performed after balloon embolization. Other cases did not have operation-related complications. The 8 patients were followed up clinically at 2 to 12 months after procedure. They did not have any neurological deficits. The modified Rankin scale (mRS) scores were 0 in 5 cases, 1 in 2 cases, and 2 in 1 case. Three patients got DSA followed-up again at 6 month after procedure. No recurrence of aneurysms was observed, and their parent arteries were patent without stenosis. Conclusion Willis covered stents were safe and effective for the treatment of some complex internal carotid artery aneurysms. Key words: Intracranial aneurysm; Carotid artery, internal; Willis covered stents