Ex vivo On-demand Conformal RFA

To further verify our proposed device, several ex vivo experiments are conducted on fresh porcine kidneys. A commercial ablation electrode (photo in Figure 14) is also used as a reference. Both electrodes are used to ablate a target tissue with same ablation parameters (ablation time, insertion depth and ablation power). To visualize and evaluate the RFA lesions, the ablated kidneys are sliced carefully at the surface where the (sub)electrode is. As illustrated in Figure 15A (i and ii), small RFA lesions with nearly circular and elliptic sectional contours are observed in almost identical shape and the measured sectional areas of RFA lesions are roughly the same. . However, the stiffer commercial electrode is impossible to steer inside the tissue, which make it hard to conform to a curved sectional shape, Figure 15A (iii). In contrast, our pre-curved electrode can steer on demand and ablate a curved sectional shape that is almost identical with the target tissue. Additionally, such an on-demand conformal ablation is also applicable for other tissues, e.g. a porcine liver in Figure 16.