Results & Discussion
According to previous research,\cite{Trujillo2013} RFA lesions are associated with biophysical properties of tissues and will conform to the shape of electrode. To match the target tumor with morphologic appearance of RFA lesions, and thus minimize unnecessary injury of normal cells, one of the most effective approaches is to properly design the electrode.\cite{Zhang2016} As shown in Figure 3A, a flexible pre-curved stylet and a relative stiff coaxial cannula are designed to tune the final expanded-out electrode shape by adjusting the relative axial position of them. Three individually-controlled sub-electrodes are integrated in one electrode for the rational control of energy output, and hence three-dimensional on-demand conformal ablation can be achieved in an efficient way.