title: Breath-hold PET/CT-guided tumour ablation under general anaesthesia: accuracy of tumour image registration and projected ablation zone overlap.
abstract: OBJECTIVE
  To assess single-breath-hold combined positron-emission tomography/computed tomography (PET/CT) for accuracy of tumour image registration and projected ablation volume overlap in patients undergoing percutaneous PET/CT-guided tumour-ablation procedures under general anaesthesia.
  
  
  METHODS
  Eight patients underwent 12 PET/CT-guided tumour-ablation procedures to treat 20 tumours in the lung, liver, or adrenal gland. Using breath-hold PET/CT, the centre of the tumour was marked on each PET and CT acquisition by four readers to assess two- (2D) and three-dimensional (3D) spatial misregistration. Overlap of PET and CT projected ablation volumes were compared using the Dice similarity coefficient (DSC). Interobserver differences were assessed with repeated measure analysis of variance (ANOVA). Technical success and local progression rates were noted.
  
  
  RESULTS
  Mean tumour 2D PET/CT misregistrations were 1.02 mm (range 0.01-5.02), 1.89 (0.03-7.85), and 3.05 (0-10) in the x, y, and z planes. Mean 3D misregistration was 4.4 mm (0.36-10.74). Mean projected PET/CT ablation volume DSC was 0.72 (±0.19). No significant interobserver differences in 3D misregistration (p=0.73) or DSC (p=0.54) were observed. Technical success of ablations was 100%; one (5.3%) of 19 tumours progressed.
  
  
  CONCLUSIONS
  Accurate spatial registration of tumours and substantial overlap of projected ablation volumes are achievable when comparing PET and CT acquisitions from single-breath-hold PET/CT. The results suggest that tumours visible only at PET could be accurately targeted and ablated using this technique.
authors.affiliation: Brigham and Women's Hospital, Department of Radiology, Abdominal Imaging & Intervention, 75 Francis St., Boston, MA 02115, USA. Electronic address: pshyn@bwh.harvard.edu.
authors.forename: P B
authors.initials: PB
authors.lastname: Shyn
authors.affiliation: Brigham and Women's Hospital, Department of Radiology, Abdominal Imaging & Intervention, 75 Francis St., Boston, MA 02115, USA.
authors.forename: S
authors.initials: S
authors.lastname: Tremblay-Paquet
authors.affiliation: Brigham and Women's Hospital, Department of Radiology, Abdominal Imaging & Intervention, 75 Francis St., Boston, MA 02115, USA.
authors.forename: K
authors.initials: K
authors.lastname: Palmer
authors.affiliation: Brigham and Women's Hospital, Department of Radiology, Abdominal Imaging & Intervention, 75 Francis St., Boston, MA 02115, USA.
authors.forename: S
authors.initials: S
authors.lastname: Tatli
authors.affiliation: Brigham and Women's Hospital, Department of Radiology, Abdominal Imaging & Intervention, 75 Francis St., Boston, MA 02115, USA.
authors.forename: K
authors.initials: K
authors.lastname: Tuncali
authors.affiliation: Brigham and Women's Hospital, Department of Radiology, Abdominal Imaging & Intervention, 75 Francis St., Boston, MA 02115, USA.
authors.forename: O I
authors.initials: OI
authors.lastname: Olubiyi
authors.affiliation: Brigham and Women's Hospital, Department of Radiology, Abdominal Imaging & Intervention, 75 Francis St., Boston, MA 02115, USA.
authors.forename: N
authors.initials: N
authors.lastname: Hata
authors.affiliation: Brigham and Women's Hospital, Department of Radiology, Abdominal Imaging & Intervention, 75 Francis St., Boston, MA 02115, USA.
authors.forename: S G
authors.initials: SG
authors.lastname: Silverman
mesh_terms: D000328:Adult; D000368:Aged; D000768:Anesthesia, General; D016477:Artifacts; D062485:Breath Holding; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009038:Motion; D009369:Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*; D015203:Reproducibility of Results; D015656:Respiratory Mechanics; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome