• 109 liver tumors were treated with radiofrequency ablation with a wet electrode under simultaneous control of impedance and temperature (Berchtold®, Tuttlingen, Germany). The study included 39 colorectal metastases (age of patients: 41-77 years old), 12 breast cancer metastases (age of patients: 44 -64 years old) and 58 hepatocellular carcinomas (HCC) (age of patients: 52-81 years old). The 18 to 16 gauge electrodes contain a coaxial lumen that enables a saline (0.9 %) interstitial infusion (1 ml/min, 40 W during 10 min).
  • The volume of NaCl injected depends on power and impedance. If the impedance is high at the beginning of the procedure, the needle position should be modified. If the impedance is still high, 10% NaCl can be used. The NaCl concentration had significant but nonlinear effects on electrical conductivity, RF deposition, and heating.
  • The Indications were:
    • Curative: HCC and colorectal liver metastases up to 4 cm in diameter
    • Palliative: HCC and colorectal liver metastases bigger than 3 cm in diameter
    • All solitary metastases resisting to conventional therapy
  • Ten days after the procedure, the patient underwent the initial MRI control. After complete necrosis of the tumor, a control MRI was performed every 3 months the ablation areas were analyzed for overall conspicuity, presence of hemorrhage, enhancement patterns, and presence of residual tumor and its pattern.
hepatocellular carcinoma
Radio frequency, ultrasound monitoring
CT control
MR evaluation: nodular pattern incomplete ablation