title: Roentgen stereophotogrammetric analysis: an accurate tool to assess stent-graft migration.
abstract: OBJECTIVE
  To evaluate in an in vitro model the feasibility and accuracy of Roentgen stereophotogrammetric analysis (RSA) versus computed tomography (CT) for the ability to detect stent-graft migration.
  
  
  METHODS
  An aortic model was constructed from a 22-mm-diameter Plexiglas tube with 6-mm polytetrafluoroethylene inlays to mimic the renal arteries. Six tantalum markers were placed in the wall of the aortic tube proximal to the renal arteries. Another 6 markers were added to a Gianturco stent, which was cast in Plexiglas and placed inside the aorta and fixed to a micromanipulator to precisely control displacement of the stent along the longitudinal axis. Sixteen migrations were analyzed with RSA software and compared to the micromanipulator. Thirty-two migrations were measured by 3 observers from CT images acquired with 16x0.5-mm beam collimation and reconstructed with a 0.5-mm slice thickness and a 0.4-mm reconstruction interval. Measurements were made with Vitrea postprocessing software using a standard clinical protocol and central lumen line reconstruction. Results of CT were also compared to the micromanipulator.
  
  
  RESULTS
  The mean RSA measurement error compared to the micromanipulator was 0.002+/-0.044 mm, and the maximum error was 0.10 mm. There was no statistically significant interobserver variability for CT (p=0.17). The pooled mean (maximum) measurement error of CT was 0.14+/-0.29 (1.00) mm, which was significantly different from the RSA measurement error (p<0.0001).
  
  
  CONCLUSIONS
  Detection of endograft migration by RSA is feasible and was significantly more accurate than CT in this nonpulsatile in vitro model.
authors.affiliation: Department of Surgery, Division of Vascular Surgery, Leiden University Medical Center, Leiden, The Netherlands. koning@lumc.nl
authors.forename: Olivier H J
authors.initials: OH
authors.lastname: Koning
authors.forename: Olivier R
authors.initials: OR
authors.lastname: Oudegeest
authors.forename: Edward R
authors.initials: ER
authors.lastname: Valstar
authors.forename: Eric H
authors.initials: EH
authors.lastname: Garling
authors.forename: Edwin
authors.initials: E
authors.lastname: van der Linden
authors.forename: Jan-Willem
authors.initials: JW
authors.lastname: Hinnen
authors.forename: Jaap F
authors.initials: JF
authors.lastname: Hamming
authors.forename: Albert M
authors.initials: AM
authors.lastname: Vossepoel
authors.forename: J Hajo
authors.initials: JH
authors.lastname: van Bockel
mesh_terms: D001027:Aortography / Q000295:instrumentation* / Q000379:methods*; D001807:Blood Vessel Prosthesis; D002138:Calibration; D005240:Feasibility Studies; D005548:Foreign-Body Migration / Q000000981:diagnostic imaging*; D006801:Humans; D008953:Models, Anatomic; D019904:Polymethyl Methacrylate; D011475:Prosthesis Failure; D012984:Software; D015607:Stents
chemical_list: D019904:Polymethyl Methacrylate