Fig. 2.

Diagram showing typical patterns of radiofrequency energy delivery during radiofrequency ablation in three groups.

A. Consecutive mode: radiofrequency (RF) energy was consecutively applied to each electrode for eight minutes by changing current flow to second electrode just after ablation with first electrode (in total 24 minutes). B. Switching monopolar mode: RF energy (- maximum 200 W) was applied to one of three electrodes and was switched between three electrode tips of Octopus® electrode depending on tissue impedance changes for total of 12 minutes. C. Dual switching mode: synchronous parallel RF energy (- maximum 400 W; 200 + 200 W) was applied to pair of three electrodes; similar to switching monopolar mode, RF energy was delivered in alternating fashion to three possible pairs of electrodes of Octopus® electrode.