Application of the Willis Covered Stent in the Treatment of CarotideCavernous Fistula: A Single-Center Experience Lun-Xin Liu 1 , Jaims Lim 2 , Chang-Wei Zhang 1 , Sen Lin 1 , Cong Wu 1 , Ting Wang 1 , Xiao-Dong Xie 1 , Liang-Xue Zhou 1 , Chao-Hua Wang 1 - BACKGROUND: The purpose of the present study was to describe our single-institutional experience of treating direct carotidecavernous fistulas (DCCFs) with Willis covered stents (WCSs). - METHODS: Of a total of 31 DCCFs, 10 were treated with WCSs (Microport, Shanghai, China) at West China Hospital from January 2015 to December 2016. The indications for treatment, perioperative findings, and postoperative and follow-up results were collected and analyzed. - RESULTS: All 10 patients had successful deployment of WCSs. Complete exclusion of the fistula was achieved in 6 patients immediately after deployment of 1 stent. Endoleak was observed in 4 patients (patients 2, 4, 5, and 9). Thus, repeat dilation of the stent with greater pres- sure was performed, which resolved the endoleak in 2 patients (patients 2 and 9). The endoleak of the other 2 patients persisted after repeat dilation of the balloon. Hence, a second stent was deployed in these 2 patients (patients 4 and 5), which eliminated the endoleak in patient 4. However, patient 5 continued to have a minimal endoleak. Nine patients had fistulas successfully occluded by WCSs during the follow-up period. One patient experienced recurrence of a DCCF at the 10-day follow-up point. We chose coil embolization to address this DCCF. No stenosis of the internal carotid artery or DCCF recurrence, except that in the abovementioned patient, was observed. - CONCLUSIONS: WCS was proved to be an alternative treatment method for complex DCCFs through reconstruc- tion and preservation of the internal carotid artery. Our study also confirmed the safety, efficacy, and midterm durability of WCSs for complex DCCFs without any serious delayed complications. INTRODUCTION D irect carotidecavernous fistulas (DCCFs) represent a direct communication between the internal carotid artery (ICA) and cavernous sinus, which Barrow et al. 1 classified as a type A fistula. Most DCCFs are traumatic; however, spontaneous fistulas originate from ruptured cavernous sinus aneurysms, thus allowing for communication between the cavernous sinus and ICA. 1-4 DCCFs can be treated by surgical repair or endovascular treatment. Owing to the difficult accessi- bility of the distal ICA via open surgical repair, endovascular therapy has become the mainstay of DCCF treatment. Detachable balloons (DBs) have been widely accepted as the classical endovascular therapeutic option for DCCFs, with reported success rates of 75%e88% in occluding the fistula and preserving the parent ICA patency. 5-10 Major risks and complications have occurred with DBs for DCCF treatment, including a relatively high rate of pseudoaneurysm formation and incomplete occlusion or reestablished flow to the DCCF after treatment. Various multimodal endovascular techniques, including coils or fluid Key words - Carotidecavernous fistula - Complication - Covered stent - Endovascular Abbreviations and Acronyms CCF: Carotidecavernous fistula CN: Cranial nerve DB: Detachable balloon DCCF: Direct carotidecavernous fistula FD: Flow diverter ICA: Internal carotid artery PTFE: Polytetrafluoroethylene WCS: Willis covered stent From the 1 Department of Neurosurgery, West China Hospital, Sichuan University, Sichuan, People’s Republic of China; and 2 Department of Neurological Surgery, University of Buffalo, Buffalo, New York, USA To whom correspondence should be addressed: Chao-Hua Wang, M.D. [E-mail: wangchaohuaHX@163.com] Citation: World Neurosurg. (2018). https://doi.org/10.1016/j.wneu.2018.10.060 Journal homepage: www.WORLDNEUROSURGERY.org Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2018 Elsevier Inc. All rights reserved. WORLD NEUROSURGERY -: e1-e9, - 2018 www.WORLDNEUROSURGERY.org e1 Original Article