title: Contrast-enhanced ultrasound imaging for aortic stent-graft surveillance.
abstract: OBJECTIVE
  To compare unenhanced and enhanced ultrasound imaging to computed tomographic angiography (CTA) or magnetic resonance angiography (MRA) for surveillance of aortic endografts.
  
  
  METHODS
  Thirty consecutive patients (29 men; mean age 69 years, range 50-82) who underwent endovascular aortic aneurysm repair agreed to participate in a follow-up program. Patients underwent CTA (26/30) or MRA (4/30), plain abdominal radiography, and unenhanced and enhanced ultrasound examinations at 3, 12, and 24 months to evaluate aneurysm diameter, endoleaks, and graft patency. The accuracy of ultrasound was compared with CTA or MRA as the reference standards.
  
  
  RESULTS
  Twenty-six patients reached the 24-month assessment (mean follow-up 30 months, range 6-60). All endoleaks detected by CTA or MRA were confirmed by enhanced ultrasound; the aneurysm diameter in these patients remained unchanged or increased. In patients without endoleaks on any imaging method, the sac diameter remained unchanged or decreased. Endoleaks disclosed by enhanced ultrasound alone, all type II, numbered 16 at 3 months, 6 at 12 months, and 3 at 24 months. In this group, the aneurysm diameter remained unchanged or increased. Enhanced ultrasound yielded 100% sensitivity in detecting endoleaks, but compared with CTA and MRA, all endoleaks detected by enhanced ultrasound alone were false positives (mean specificity 65%). Nevertheless, because changes in the postoperative aneurysm diameter were similar in patients with endoleaks detectable on CTA/MRA and on enhanced ultrasound ("true positives") and in those with endoleaks detectable only on enhanced ultrasound ("false positives"), some endoleaks were possibly "true positive" results.
  
  
  CONCLUSIONS
  Enhanced ultrasound is a useful method in the long-term surveillance of endovascular aortic aneurysm repairs, possibly in association with CTA or MRA. Enhanced ultrasound also seems able to identify endoleaks missed by other imaging techniques, but this conclusion awaits further investigation.
authors.affiliation: Department of Vascular Surgery, University of Rome La Sapienza, Rome, Italy. mariafabrizia.giannoni@uniroma1.it
authors.forename: Maria Fabrizia
authors.initials: MF
authors.lastname: Giannoni
authors.forename: Giovanni
authors.initials: G
authors.lastname: Palombo
authors.forename: Enrico
authors.initials: E
authors.lastname: Sbarigia
authors.forename: Francesco
authors.initials: F
authors.lastname: Speziale
authors.forename: Alvaro
authors.initials: A
authors.lastname: Zaccaria
authors.forename: Paolo
authors.initials: P
authors.lastname: Fiorani
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017130:Angioplasty; D001014:Aortic Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery; D019917:Blood Vessel Prosthesis Implantation; D003287:Contrast Media; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D018615:Ultrasonography, Doppler, Color
chemical_list: D003287:Contrast Media