title: Follow-up of abdominal aortic aneurysm after endovascular aortic repair: comparison of volumetric and diametric measurement.
abstract: OBJECTIVE
  To determine the correlation of maximal diameter measurements with volumetric evaluation of size after endovascular aortic repair (EVAR) of abdominal aortic aneurysms (AAA) using computed tomography angiography (CTA) and to survey its applicability for clinical follow-up.
  
  
  METHODS
  73 consecutive patients (2 females, 71 males; age 38-84 years; mean age, 69.1 ± 8 years) with AAA were treated with percutaneous EVAR in a single institution. For follow-up, CTA was performed periodically after EVAR. Images were evaluated for maximal diameter in consensus by two experienced radiologists. Using OsirixTM, volumetric measurements were done by one radiologist, including the entire infrarenal abdominal aorta.
  
  
  RESULTS
  In 73 patients 220 CTA examinations were performed after EVAR with a mean follow-up of 17.3 months (range, 1.8-42.7 months). The mean postinterventional volume of aneurysm was 165.63 ml ± 93.29 ml (range, 47.94-565.67 ml). The mean maximal postinterventional diameter was 5.91 ± 1.52 cm (range, 3.72-13.82 cm). At large over the entire observation period a slight, non-significant decrease of 1.6% (2.58ml ± 69.05 ml, range 82.82-201.92 ml) in volumes and a 9.3% (mean 0.55 cm ± 1.22 cm, range 2.85-1.93cm) in diameters were observed. For all examinations a high correlation of volume and diameter was calculated (r = 0.813-0.905; α<0.01).
  
  
  CONCLUSIONS
  For follow-up of abdominal EVAR using CTA there is a high correlation between volumetric and diametric measurements of aneurysm. Based on a daily clinical routine setting, measurements of maximal diameters in cross sectional imaging of AAA after EVAR seems to be sufficient to exclude post interventional enlargement.
authors.affiliation: University Medical Center Hamburg-Eppendorf, Center for Radiology and Endoscopy, Department of Diagnostic and Interventional Radiology, Martinistrasse 52, 20246 Hamburg, Germany. jhahne@uke.de
authors.forename: J D
authors.initials: JD
authors.lastname: Hahne
authors.forename: C
authors.initials: C
authors.lastname: Arndt
authors.forename: J
authors.initials: J
authors.lastname: Herrmann
authors.forename: B
authors.initials: B
authors.lastname: Schönnagel
authors.forename: G
authors.initials: G
authors.lastname: Adam
authors.forename: C R
authors.initials: CR
authors.lastname: Habermann
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015901:Angiography, Digital Subtraction; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging* / Q000601:surgery*; D057510:Endovascular Procedures / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome