title: Is aortic angiography necessary for accurate planning of endovascular aortic aneurysm stents?
abstract: Endovascular management of abdominal aortic aneurysms (AAA) relies upon accurate stent design. We hypothesized the length of the stent could be measured from computed tomogram (CT) generated 3D surface rendered images of the abdominal vessels, eliminating the need for digital subtraction angiography (DSA).
  
  
  METHODS
  The CT scans from a consecutive series of 54 patients considered for endovascular AAA repair were reviewed. A TRIFAB Zenith (Cook) endovascular aortic stent was designed, using the manufacturer's sizing computer program. These hypothetical stents were compared to those that had been implanted, using measurements from both angiogram and CT (Spearman's test of correlation (p<0.05)).
  
  
  RESULTS
  The stent body size and short limb extension (SLE) of stents in each group was similar (correlation coefficient 0.70(p<0.01) and 0.50 (p=0.014)), however, CT alone significantly underestimated the length of the long limb extension (LLE) (correlation coefficient 0.095).
  
  
  CONCLUSIONS
  These data suggest that CT underestimates the tortuosity of iliac vessels. Aortic angiography is necessary for accurate AAA endovascular stent design.
authors.affiliation: Department of Surgery, Launceston General Hospital, Tasmania, Launceston, Australia.
authors.forename: Wendy A
authors.initials: WA
authors.lastname: Brown
authors.forename: Robert
authors.initials: R
authors.lastname: Miller
authors.forename: Simone
authors.initials: S
authors.lastname: Birch
authors.forename: Alan
authors.initials: A
authors.lastname: Scott
mesh_terms: D015901:Angiography, Digital Subtraction; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging* / Q000628:therapy*; D001027:Aortography; D019917:Blood Vessel Prosthesis Implantation / Q000379:methods; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D011300:Preoperative Care / Q000379:methods; D011474:Prosthesis Design; D015203:Reproducibility of Results; D015607:Stents; D014057:Tomography, X-Ray Computed