title: [Pathogenesis of in-stent thrombosis after carotid artery stenting].
abstract: OBJECTIVE
  In-stent thrombosis (IST) after carotid artery stenting (CAS) is a rare complication that can lead to severe thromboembolic events. The purpose of this study was to investigate the pathogenesis of IST after CAS.
  
  
  METHODS
  A total of 101 patients underwent CAS from January 2006 to September 2013 at our hospital. Five of these patients experienced IST. We reviewed their clinical course and treatment. In addition, we compared various parameters, including basal disease, preceding anti-platelet therapy, rate of stenosis, length of stenosis, preoperative examination, type of stent, length of stent, post dilatation, and postoperative examination, between the IST and the non-IST groups.
  
  
  RESULTS
  All cases in the IST group had low echoic plaque and open cell stent, and all thrombi were located at the dorsal side of the internal carotid artery and the distal side of the stent flexion. Four cases without neurological symptoms were found to have resolution of IST at 3-6 weeks after CAS with anticoagulant therapy. One case had symptomatic thromboembolism at 1 month after CAS, and the thrombus was removed along with the stent due to growth of the thrombus despite anticoagulant therapy. No significant differences were observed between the IST and non-IST groups with regard to the factors described in the methods section.
  
  
  CONCLUSIONS
  This study did not identify factors related to IST. We hypothesize that soft plaque can easily protuberate in the context of a stent with a large cell and that protrusion plaque may increase the risk of thrombus formation in combination with turbulent flow at the site of stent flexion. Further investigation in a larger number of patients is needed to clarify the risk factors related to IST.
authors.affiliation: Department of Neurosurgery, Ehime University Graduation School of Medicine.
authors.forename: Saya
authors.initials: S
authors.lastname: Ozaki
authors.forename: Masahiko
authors.initials: M
authors.lastname: Tagawa
authors.forename: Shirabe
authors.initials: S
authors.lastname: Matsumoto
authors.forename: Akihiro
authors.initials: A
authors.lastname: Inoue
authors.forename: Hideaki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Kumon
authors.forename: Takanori
authors.initials: T
authors.lastname: Oonishi
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000601:surgery*; D016893:Carotid Stenosis / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D013927:Thrombosis / Q000209:etiology / Q000473:pathology / Q000601:surgery*