title: Prediction of the ablated area by the spread of microbubbles during radiofrequency ablation of hepatocellular carcinoma.
abstract: OBJECTIVE
  Radiofrequency ablation (RFA) is effective for the treatment of hepatocellular carcinoma (HCC). To prevent the ablation of adjacent organs and vessels, the spread of microbubbles generated by heating during RFA was observed by ultrasonography (US) and used to predict the ablated area; however, several reports documented that discrepancies existed between the spread of microbubbles and the ablated area.
  
  
  METHODS
  The spread of microbubbles during RFA was observed by US in 24 patients with HCC and the areas were compared with the defect of enhancement in contrast enhanced (CE)-US, using Levovist in the same plane.
  
  
  RESULTS
  During the ablation, the posterior margin was obscure but the border could be visualized 5 min after the ablation. The size of the area of hyperechogenicity 5 min after ablation and that of the defect observed by CE-US was found to correlate (r(2)=0.91, P<0.0001). The shape of the hyperechogenicity corresponded well to the defect area, even in cases showing irregular spread of the microbubbles.
  
  
  CONCLUSIONS
  The observation of microbubbles during RFA can predict the ablated area and might be useful to prevent the unfavorable ablation of adjacent organs and vessels.
authors.affiliation: Department of Internal Medicine, Hiroshima City Hospital, 7-33 Motomachi, Naka-ku, Hiroshima-city, Hiroshima 730-8518, Japan. nouso@cc.okayama-u.ac.jp
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Nouso
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Shiraga
authors.forename: Shuji
authors.initials: S
authors.lastname: Uematsu
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Okamoto
authors.forename: Ryo
authors.initials: R
authors.lastname: Harada
authors.forename: Shoko
authors.initials: S
authors.lastname: Takayama
authors.forename: Wakako
authors.initials: W
authors.lastname: Kawai
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kimura
authors.forename: Toru
authors.initials: T
authors.lastname: Ueki
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Okano
authors.forename: Masahiko
authors.initials: M
authors.lastname: Nakagawa
authors.forename: Motowo
authors.initials: M
authors.lastname: Mizuno
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Araki
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Shiratori
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography