title: Needle electrode position assessed using three-dimensional ultrasonography and outcome of radiofrequency ablation in hepatocellular carcinoma.
abstract: OBJECTIVE
  Radiofrequency ablation (RFA) is an established curative therapy for early-stage hepatocellular carcinoma (HCC). We assessed the positions of inserted needle electrodes using three-dimensional ultrasonography (3D-US) and examined the association between the electrode position and outcomes of RFA.
  
  
  METHODS
  Forty-seven patients with 49 HCC nodules treated with a cooled-tip RFA system were enrolled. Immediately after the first insertion of electrodes, 3D volume data were acquired. After RFA completion, the electrode position was assessed using the data.
  
  
  RESULTS
  There were 18 central and 31 marginal pattern nodules. The total number of electrode insertions was significantly greater for the marginal nodules than for the central nodules (p=0.032). In the first session of RFA, 36 HCC nodules (central, n=14; marginal, n=22) were treated with single insertion of electrodes. The ratio of incompletely ablated nodules after the first session was greater for the marginal nodules than for the central nodules (p=0.025).
  
  
  CONCLUSIONS
  Our study demonstrated that inserted electrode positions assessed using 3D-US are closely associated with outcomes of RFA and the number of electrode insertions.
authors.affiliation: Department of Gastroenterology and Hepatology, Kurashiki Central Hospital, Kurashiki, Japan. n.toshikuni@gmail.com
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Toshikuni
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Takuma
authors.forename: Junko
authors.initials: J
authors.lastname: Tomokuni
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D053208:Kaplan-Meier Estimate; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D008297:Male; D009339:Needles; D009364:Neoplasm Recurrence, Local; D011446:Prospective Studies; D025321:Surgery, Computer-Assisted; D013997:Time Factors; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional