title: Delayed Stenosis in the Intracranial Vessels following Endovascular Treatment for Acute Stroke.
abstract: OBJECTIVE
  To evaluate delayed stenosis of the vessels after endovascular thrombectomy using magnetic resonance (MR) angiography.
  
  
  METHODS
  Of 82 consecutive patients who underwent successful endovascular treatment for acute intracranial large vessel occlusion between October 2010 and October 2014 at a single institution, 57 patients for whom 3-month radiologic follow-up examinations using MR angiography were available were included in the analysis. MR angiography images were assessed to detect delayed stenosis, which was defined as a decrease in the diameter of treated vessels > 50% compared with MR angiography images obtained 24 hours after endovascular treatment.
  
  
  RESULTS
  MR angiography images obtained 3 months after endovascular treatment revealed delayed stenosis of treated vessels in five (8.8%) of 57 patients. All cases of delayed stenosis were asymptomatic and occurred in the middle cerebral artery (MCA). Further serial radiologic follow-up showed gradual improvement of all delayed stenosis over 12 months.
  
  
  CONCLUSIONS
  Endovascular treatment poses a risk of delayed stenosis of treated vessels, especially in the MCA. MR angiography is a useful modality in long-term follow-up to evaluate delayed stenosis after endovascular treatment.
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan. Electronic address: enomoto@gifu-u.ac.jp.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Enomoto
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Takagi
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Matsubara
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Tsujimoto
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Yamauchi
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Hyogo Medical University, Hyogo, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Yoshimura
authors.affiliation: Department of Neurosurgery, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Iwama
mesh_terms: D000368:Aged; D015984:Causality; D015897:Comorbidity; D057510:Endovascular Procedures / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000453:epidemiology* / Q000473:pathology; D007564:Japan / Q000453:epidemiology; D008137:Longitudinal Studies; D018810:Magnetic Resonance Angiography / Q000706:statistics & numerical data; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology* / Q000473:pathology; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery*; D017131:Thrombectomy / Q000706:statistics & numerical data*; D016896:Treatment Outcome