title: Evaluation of In-Stent Restenosis After Stent Implantation in the Vertebral Artery Ostium by Multislice Computed Tomography Angiography: Factors Affecting Accurate Diagnosis.
abstract: OBJECTIVE
  Few articles have evaluated vertebral artery ostium stents using multislice computed tomography (CT). The purpose of our study was to evaluate the diagnostic performance of 64- and 16-slice CT for detecting significant in-stent restenosis after vertebral artery ostium stenting, and to identify factors affecting the accurate diagnosis by CT.
  
  
  METHODS
  We reviewed 57 stents scanned using 64-slice CT and 34 stents using 16-slice CT. The accuracy of CT for diagnosing significant in-stent restenosis (≥ 50% diameter narrowing) was calculated using conventional angiography as a reference standard. Possible factors influencing the diagnostic performance of CT were analyzed, such as CT scanner, image quality, and stent characteristics.
  
  
  RESULTS
  With 64-slice CT, 46 (80.7%) of 57 stents were classified as evaluable, while with 16-slice CT, 28 (82.3%) of 34 stents were classified as evaluable. No stents with diameters ≤ 2.75 mm were evaluable. The respective results for 64- versus 16-slice CT were sensitivity 87.5% (95% confidence interval [CI] 47.3-99.7%) versus 100% (95% CI 15.8-100.0%), specificity 94.7% (95% CI 82.3%-99.4%) versus 96.2% (95% CI 80.4-99.9%). Factors reducing the accurate diagnosis were those associated with poor image quality, a diameter ≤ 2.75 mm, and drug-eluting stent type (p < 0.05).
  
  
  CONCLUSIONS
  64-slice and 16-slice CT scans are adequate in stents with diameters > 2.75 mm for the evaluation of in-stent restenosis after stent implantation in the vertebral artery ostium.
authors.affiliation: Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, 137-701, Seoul, Republic of Korea.|Department of Radiology, Eulji University Hospital, Seo-gu Dunsan-dong 106, 302-799, Daejeon, Republic of Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Lee
authors.affiliation: Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, 137-701, Seoul, Republic of Korea.
authors.forename: Y S
authors.initials: YS
authors.lastname: Lim
authors.affiliation: Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, 137-701, Seoul, Republic of Korea.
authors.forename: H W
authors.initials: HW
authors.lastname: Lim
authors.affiliation: Department of Radiology, Eulji University Hospital, Seo-gu Dunsan-dong 106, 302-799, Daejeon, Republic of Korea.
authors.forename: I K
authors.initials: IK
authors.lastname: Yu
authors.affiliation: Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, 137-701, Seoul, Republic of Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Radiology, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, 137-701, Seoul, Republic of Korea. wjyu@catholic.ac.kr.
authors.forename: W J
authors.initials: WJ
authors.lastname: Yoo
mesh_terms: D000328:Adult; D000368:Aged; D000792:Angiography / Q000379:methods; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging* / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D011856:Radiographic Image Enhancement / Q000379:methods; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D015607:Stents / Q000009:adverse effects*; D016896:Treatment Outcome; D014715:Vertebrobasilar Insufficiency / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy*
keywords: CT angiography; In-stent restenosis; Stent; Vertebral artery