title: In-stent stenosis in the patient with internal carotid aneurysm after treated by the Willis covered stent: Two case reports and literature review.
abstract: In-stent stenosis after treated by Willis covered stent-case reports.
  
  
  BACKGROUND
  Advancements in minimally invasive technology have allowed endovascular reconstruction of internal carotid aneurysm. However, in-stent stenosis is an important and well-characterized complication of stenting after the treatment of internal carotid aneurysm.
  
  
  METHODS
  We would present 2 patients who were diagnosed with in-stent stenosis after the treatment of Willis covered stent. Case 1: A 57-year-old female with 2-week history of headache and vomiting before admission, whose digital subtraction angiography (DSA) demonstrated left internal carotid C6 aneurysm and showed about 20% stenosis 3 months later since operation in the position where Willis covered stent was deployed. Case 2: A 23-year-old male with skull base fracture, subarachnoid hemorrhage, right femoral fracture for 14 days and epistaxis for 9 hours caused by a car accident, whose DSA demonstrated left internal carotid paracliniod pseudoaneurysm. One year later, the patient went to our center again because he had headache and dizziness for 6 months after the interventional operation. His DSA demonstrated about 80% stenosis in the position where Willis covered stent was deployed. The clinical and radiologic characteristics and the experience in dealing with the stenosis are presented.
  
  
  CONCLUSIONS
  In-stent stenosis after treated with Willis covered is uncommon, but not rare. Operators should pay more attention to the in-stent stenosis during the period of follow-up observation and monitor P2Y12 Reaction Unit (PRU) in the antiplatelet period, especially for the Willis covered stent. What is more, the treatment for stenosis ought to be carefully considered.
authors.affiliation: Department of Neurosurgery, West China Hospital School of Basic Science and Forensic Medicine, Sichuan University, Chengdu, Sichuan, People's Republic of China.
authors.forename: Lun-Xin
authors.initials: LX
authors.lastname: Liu
authors.forename: Meng-Yuan
authors.initials: MY
authors.lastname: Song
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Xie
mesh_terms: D020212:Carotid Artery Injuries / Q000000981:diagnostic imaging / Q000601:surgery*; D002343:Carotid Artery, Internal / Q000601:surgery*; D002533:Cerebral Angiography; D003251:Constriction, Pathologic; D057510:Endovascular Procedures; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015607:Stents / Q000009:adverse effects*; D055815:Young Adult