Endovascular Treatment Of Intracranial Aneurysms With The Willis Covered Stent

Objective:To investigate the efficacy and safety of the Willis covered stent in treating intracranial aneurysms(including distal internal carotid artery aneurysms and vertebral artery dissecting aneurysms).Methods:Records of all 42 patients with DICA aneurysms or VADAs treated with the Willis covered stents at our institute between July 2014 and January 2019 were retrospectively examined.The patients’ demographic information,symptoms,diagnosis,treatment procedure,and immediate and follow-up clinical and angiographic outcomes were extracted.Results:A total of 47 Willis-covered stents were implanted in 42 patients(43 aneurysms).One stent fell off to the M2 segment of the right middle cerebral artery,and the other 46 stents were successfully implanted into the parent artery.Immediate complete aneurysm occlusion was achieved in 37 patients(88.9%),endoleak occurred in 5 patients(11.1%).2patients died post-operatively from procedure-related complications,another one die from reasons unrelated to the procedure.In the remaining 39 patients,non-lethal complications occurred in 4 patients including ptosis and diplopia of the right eye,intra-operative hemorrhage and carotid cavernous fistulas.Angiographic and clinical follow-ups(means ±standard deviation: 8.8 ± 5.3 months)were done in 32 patients(33 aneurysms).Complete occlusion was maintained in all of the 33 aneurysms.2 of the 32 patients had asymptomatic parent artery occlusion.No ischemic or hemorrhagic event occurred during the follow-up period.The modified Rankin Scale score was 0 in 31 patients and 1 in the remaining 1 patient.Conclusions:The Willis covered stent can be a safe and effective treatment for complex DICA aneurysms and VADAs.Its safety and effectiveness need to be further confirmed by long-term follow-up and a large sample of randomized controlled studies.