Figure 2
US images (harmonic imaging) before (a), during (b, c) and after (d) RF ablation in pig liver (please find embedded scale distance). The electrode alone is visible during the planning period, before RF heating (a, see the red arrow). During RF ablation, the gas bubbles created around the electrode are clearly seen in the early (b) and late (c) stages of the procedure. No gas bubbles are visible one minute after the end point of RF ablation due to wash-out with perfusion (d).