In Vivo Experimental Study of an Endoscopic Ultrasound Multifunctional Radiofrequency Ablation Probe

The aim of our study was to test the feasibility of a new developed RFA probe made especially for EUS use and also capable of injecting iron oxide nanoparticles within the targeted liver area. The procedures were performed on domestic pigs, divided in groups: A.liver RFA was performed; B -IONs were injected in the liver followed by EUS-RFA in the same area; C.local EUS-guided liver IONs injection were performed. After EUS measurements for the ablation areas, group A had a mean of 4.9 cm, while group B had a mean of 5.2 cm (Fig.3, 4). IONs exposure was on a median area of 3.1 cm. EUS imaging pointed out a regular oval shape in group A, and a slightly irregular outline on group B, with more echo bubbles around. MRI sections revealed different patterns for each group separately. In group A and B, RFA lesions were easily identified with specific liver parenchyma changes. Group B revealed few deposits of nanoparticles further away from the targeted point. The last group pointed out a large amount of IONs within the injection region and a larger amount of dispersed IONs within the liver than group B.