title: 3T magnetic resonance imaging accurately depicts radiofrequency ablation zones in a blood-perfused bovine liver model.
abstract: OBJECTIVE
  To determine if noncontrast T1-weighted (T1W) images from 3T magnetic resonance (MR) imaging accurately depict radiofrequency (RF) ablation zones as determined macroscopically and microscopically in a blood-perfused bovine liver model.
  
  
  METHODS
  Three-dimensional (3D) gradient-recalled echo (GRE) T1W images were obtained on a 3T MR imaging scanner after RF ablations (n = 14) of in vitro blood-perfused bovine livers. The resulting central hypointense and peripheral hyperintense signal regions were measured and compared with the inner tan and outer red zones of the gross specimen. Corresponding ablated hepatic tissue samples were examined microscopically and stained with nicotinamide adenine dinucleotide phosphate (NADPH) to assess for the presence or absence of NADPH diaphorase activity. Bootstrap two-sample hypothesis tests were used to compare MR imaging, gross, and histopathologic measurements.
  
  
  RESULTS
  The MR imaging inner ablation zone had a mean radius of 0.80 cm (range 0.33-1.14 cm); the inner zone plus the outer ablation zone had a mean radius of 1.40 cm (range 1.01-1.74 cm). Comparison of the measurements of the inner ablation zone on MR imaging versus the gross specimen showed equivalence (95% confidence interval [CI] -0.122 cm, 0.223 cm). Comparison of the measurements of the outer ablation zone on MR imaging versus the gross and histologic specimens also showed equivalence (95% CI -0.095 cm, 0.244 cm, and -0.146 cm, 0.142 cm).
  
  
  CONCLUSIONS
  Noncontrast 3D GRE T1W 3T MR imaging accurately depicts the RF ablation zones in a blood-perfused bovine liver model and can be used as a noninvasive means to assess the 3D morphologic characteristics of RF ablation lesions in the model.
authors.affiliation: Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
authors.forename: Stephanie K
authors.initials: SK
authors.lastname: Burns
authors.forename: Gerald D
authors.initials: GD
authors.lastname: Dodd
authors.forename: Linda M
authors.initials: LM
authors.lastname: McManus
authors.forename: Rex A
authors.initials: RA
authors.lastname: Cardan
authors.forename: Qi
authors.initials: Q
authors.lastname: Peng
authors.forename: Michael D
authors.initials: MD
authors.lastname: Orsi
authors.forename: Hayden W
authors.initials: HW
authors.lastname: Head
authors.forename: Dana L
authors.initials: DL
authors.lastname: Blakemore
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Blume
authors.forename: Gary D
authors.initials: GD
authors.lastname: Fullerton
authors.forename: Tyler J
authors.initials: TJ
authors.lastname: Green
mesh_terms: D000818:Animals; D017115:Catheter Ablation; D002417:Cattle; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008099:Liver / Q000098:blood supply* / Q000201:enzymology / Q000473:pathology / Q000601:surgery*; D008102:Liver Circulation; D008279:Magnetic Resonance Imaging; D023421:Models, Animal; D009252:NADPH Dehydrogenase / Q000032:analysis; D010477:Perfusion; D013194:Staining and Labeling
chemical_list: D009252:NADPH Dehydrogenase