title: Usefulness of radiofrequency ablation with micro-convex probe for hepatocellular carcinoma.
abstract: OBJECTIVE
  It was aimed to assess whether a micro-convex probe is superior to the present conventional probe for ultrasonography from the points of safety and efficacy during percutaneous radiofrequency ablation therapy for hepatocellular carcinoma.
  
  
  METHODS
  Twenty-one patients with 23 hepatocellular carcinoma lesions who had one or 2 lesions, each 4 cm or less in diameter, and liver function of Child-Pugh class A or B were enrolled. All the patients except for 2 patients were seropositive for hepatitis C virus. Radiofrequency ablation was carried out under a real-time US guidance. The cooled-tip electrodes used were single and clustered.
  
  
  RESULTS
  It was possible to perform safe and accurate percutaneous radiofrequency ablation procedure using micro-convex probes for the treatment of all hepatocellular carcinoma nodules. It was also possible to treat hepatocellular carcinoma located in the right subphrenic region without artificial pleural effusion under intercostal ultrasonography guide. Improved clustered needles were successfully applied to treat the nodules more than 3 cm in diameter with less resistance for penetration compared with the conventional needle. The findings of advanced dynamic flow image on ultrasonography to assess the therapeutic efficacy indicated the consistency with those of dynamic CT which was done 3 to 5 days later radiofrequency ablation. Major complication of radiofrequency ablation procedure was noted in none.
  
  
  CONCLUSIONS
  These results suggest that micro-convex probe with clustered tips is superior to conventional probe for ultrasonography from the points of safety and efficacy during radiofrequency ablation for hepatocellular carcinoma nodule located in the right subphrenic region and for larger sized nodule more than 3 cm.
authors.affiliation: Department of Internal Medicine, Division of Gastroenterology, Aichi Medical University School of Medicine, Aichi, Japan. naokiki@aol.com
authors.forename: Naoki
authors.initials: N
authors.lastname: Hotta
authors.forename: Minoru
authors.initials: M
authors.lastname: Ayada
authors.forename: Eiji
authors.initials: E
authors.lastname: Matsumoto
authors.forename: Akihiko
authors.initials: A
authors.lastname: Okumura
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ishikawa
authors.forename: Ken
authors.initials: K
authors.lastname: Sato
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Oohashi
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kakumu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008111:Liver Function Tests; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D018084:Ultrasonography, Interventional