title: Flat-detector computed tomography in the assessment of intracranial stents: comparison with multi detector CT and conventional angiography in a new animal model.
abstract: OBJECTIVE
  Careful follow up is necessary after intracranial stenting because in-stent restenosis (ISR) or residual stenosis (RS) is not rare. A minimally invasive follow-up imaging technique is desirable. The objective was to compare the visualisation of stents in Flat Detector-CT Angiography (FD-CTA) after intravenous contrast medium injection (i.v.) with Multi Detector Computed Tomography Angiography (MD-CTA) and Digital Subtracted Angiography (DSA) in an animal model.
  
  
  METHODS
  Stents were implanted in the carotid artery of 12 rabbits. In 6 a residual stenosis (RS) was surgically created. Imaging was performed using FD-CTA, MD-CTA and DSA. Measurements of the inner and outer diameter and cross-section area of the stents were performed. Stenosis grade was calculated.
  
  
  RESULTS
  In subjective evaluation FD-CTA was superior to MD-CTA. FD-CTA was more accurate compared with DSA than MD-CTA. Cross-sectional area of the stent lumen was significantly larger (p < 0.05) in FD-CTA in comparison to MD-CTA. Accurate evaluation of stenosis was impossible in MD-CTA. There was no statistically significant difference in the stenosis grade of DSA and FD-CTA.
  
  
  CONCLUSIONS
  Our results show that visualisation of stent and stenosis using intravenous FD-CTA compares favourably with DSA and may replace DSA in the follow-up of patients treated with intracranial stents.
authors.affiliation: Department of Neuroradiology, University of Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany. tobias.struffert@uk-erlangen.de
authors.forename: Tobias
authors.initials: T
authors.lastname: Struffert
authors.forename: Sabine
authors.initials: S
authors.lastname: Ott
authors.forename: Edyta
authors.initials: E
authors.lastname: Adamek
authors.forename: Marc
authors.initials: M
authors.lastname: Schwarz
authors.forename: Tobias
authors.initials: T
authors.lastname: Engelhorn
authors.forename: Stephan
authors.initials: S
authors.lastname: Kloska
authors.forename: Yu
authors.initials: Y
authors.lastname: Deuerling-Zheng
authors.forename: Arnd
authors.initials: A
authors.lastname: Doerfler
mesh_terms: D015901:Angiography, Digital Subtraction; D000818:Animals; D002533:Cerebral Angiography / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage; D007091:Image Processing, Computer-Assisted; D011817:Rabbits; D018709:Statistics, Nonparametric; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D003287:Contrast Media