Related Experiment Video
Updated: May 15, 2026
Evaluation of the Feasibility, Safety, and Accuracy of an Intraoperative High-intensity Focused Ultrasound Device for Treating Liver Metastases
Published on: January 9, 2019
Randomized controlled trial of a new procedure of radiofrequency ablation using an expandable needle for
Miharu Hirakawa1, Kenji Ikeda, Masahiro Kobayashi
1Health Management Center, Toranomon Hospital.
Aim:
To evaluate the efficacy of a new ablation procedure for the stepwise hook extension technique using a SuperSlim needle for radiofrequency ablation (RFA) treatment of hepatocellular carcinoma (HCC), a randomized controlled trial was performed.
Methods:
Thirty patients with HCC measuring 20 mm or less were randomly treated with a conventional four stepwise expansion technique (group 1) and the new stepwise expansion technique (group 2; the electrode was closed in the shaft after the same three steps of the conventional procedure and then fully extended). All patients underwent the RFA procedure using a 10-hook expandable electrode of 17-G diameter (LeVeen SuperSlim 30 mm). We compared the ablation time, required energy and ablated lesions in the two groups.
Results:
The long and short diameters of RFA-induced necrosis were significantly larger in group 2 (37 and 28 mm) than group 1 (30 and 26 mm, P = 0.001 and =0.045, respectively). Irregular and small needle expansion resulting in the parachute-like or irregularly shaped ablated zone was observed in more cases in group 1 than in group 2. The new technique made all tines expand uniformly and largely, which produced a near-oval ablated zone of which the long axis is perpendicular to the needle shaft.
Conclusion:
The two kinds of stepwise procedures allow the selection of a more suitable procedure according to the tumor size and shape in each RFA.
