title: 3D contrast enhanced ultrasound for detecting endoleak following endovascular aneurysm repair (EVAR).
abstract: OBJECTIVE
  CT angiography (CTA) for endovascular aneurysm repair (EVAR) surveillance involves irradiation and nephrotoxic X-ray contrast agents. Three-dimensional contrast enhanced ultrasound (3D CEUS) is a novel imaging technique that may be more sensitive to blood flow detection than CTA or 2D CEUS. 3D CEUS utilises positional information from magnetic field emitters to assemble all ultrasound reflections into a high-definition image. We compared 3D CEUS with CTA for the detection of endoleak and aneurysm expansion following EVAR.
  
  
  METHODS
  3D CEUS (Curefab), 2D CEUS (Philips IU22), and CTA were compared in 30-paired images from 23 patients. Sensitivity, specificity, positive, and negative predictive value were calculated for 2D and 3D CEUS against CTA as the 'gold standard'. Pearson correlation was used to compare aneurysm sac diameter. Data were analysed using SPSS version 19.0.
  
  
  RESULTS
  30 paired 3D CEUS and CTA images were analysed from 23 patients. Endoleaks were detected in 17 images with CTA, 18 on 2D CEUS, and 18 on 3D CEUS. The sensitivity, specificity, positive, and negative predictive values of 3D CEUS to detect endoleak were 100%, 92%, 94%, and 100%, respectively. There was excellent correlation (r=0.935; p≤.0001) between CTA and 3D CEUS for AAA sac diameter. Only 3D CEUS detected the inflow and outflow arteries in all 18 scans with endoleak. 2D CEUS detected the inflow in 16 (88.8%) and CTA on 12 (66.6%) of the images.
  
  
  CONCLUSIONS
  3D CEUS may be more sensitive to endoleak following EVAR than either 2D CEUS or CTA.
authors.affiliation: Institute of Cardiovascular Sciences, University Hospital of South Manchester, Manchester, UK.
authors.forename: A
authors.initials: A
authors.lastname: Abbas
authors.affiliation: Institute of Cardiovascular Sciences, University Hospital of South Manchester, Manchester, UK.
authors.forename: V
authors.initials: V
authors.lastname: Hansrani
authors.affiliation: Independent Vascular Services, South Manchester University Hospital Trust, Manchester, UK.
authors.forename: N
authors.initials: N
authors.lastname: Sedgwick
authors.affiliation: Vascular Surgery Department, University Hospital of South Manchester, Manchester, UK.
authors.forename: J
authors.initials: J
authors.lastname: Ghosh
authors.affiliation: Institute of Cardiovascular Sciences, University Hospital of South Manchester, Manchester, UK. Electronic address: charles.mccollum@manchester.ac.uk.
authors.forename: C N
authors.initials: CN
authors.lastname: McCollum
mesh_terms: D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D001027:Aortography; D003287:Contrast Media; D057867:Endoleak / Q000000981:diagnostic imaging* / Q000209:etiology; D057510:Endovascular Procedures / Q000009:adverse effects* / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D010865:Pilot Projects; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D018615:Ultrasonography, Doppler, Color / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: 3D ultrasound; Abdominal aortic aneurysm; Endoleak; Endovascular aneurysm repair; Surveillance