title: Long-term follow-up of neck expansion after endovascular aortic aneurysm repair.
abstract: OBJECTIVE
  This study determined the rate, extent, and clinical significance of neck dilatation after endovascular aneurysm repair (EVAR).
  
  
  METHODS
  The study included 46 patients who underwent elective EVAR using bifurcated Zenith stent grafts (Cook, Bloomington, Ind) and had at least 48 months of clinical and radiographic follow-up. Computed tomography images were analyzed on a 3-dimensional workstation (TeraRecon, San Mateo, Calif). Neck diameter was measured 10 mm below the most inferior renal artery in planes orthogonal to the aorta. Nominal stent graft diameter was obtained from implantation records.
  
  
  RESULTS
  Median follow-up was 59 months (range, 48-120 months). Neck dilation occurred in all 46 patients. The rate of neck dilation was greatest at early follow-up intervals. At 48 months, median neck dilation was 5.3 mm (range, 2.3-9.8 mm). The extent of neck dilation at 48 months correlated with percentage of stent graft oversizing (Spearman rho = 0.61, P < .001). No type I endoleak or migration >5 mm occurred.
  
  
  CONCLUSIONS
  After EVAR with the Zenith stent graft, the neck dilates until its diameter approximates the diameter of the stent graft. Neck dilation was not associated with type I endoleak or migration of the stent graft.
authors.affiliation: Division of Vascular Surgery, University of California, San Francisco, Calif 94143-0222, USA.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Monahan
authors.forename: Timothy A M
authors.initials: TA
authors.lastname: Chuter
authors.forename: Linda M
authors.initials: LM
authors.lastname: Reilly
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Rapp
authors.forename: Jade S
authors.initials: JS
authors.lastname: Hiramoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001014:Aortic Aneurysm / Q000000981:diagnostic imaging / Q000601:surgery*; D001027:Aortography / Q000379:methods; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation; D004108:Dilatation, Pathologic; D005260:Female; D006801:Humans; D008297:Male; D011474:Prosthesis Design; D012495:San Francisco; D015607:Stents; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome