Morphologic characterization of RFA lesions. (A) Conformal ablation of our electrode. (B) Simulated ablated volume and its corresponding impedance under different ablation time (the stylet and cannula are fully expanded). (C) Simulation results of the relation between ablated volume and the expanded length of electrode. (D) Simulation results of the relation between ablated volume and the applied voltage. (E) Influence of number of expanded tines to ablated volumes and shapes. (F) Impact of shapes of tines on the ablated volumes and shapes.