An in-vitro animal experiment on metal implants' thermal effect on radiofrequency ablation

Background: To explore metal implants' thermal effect on radiofrequency ablation (RFA) and ascertain distance-thermal relationship between the metal implants and radiofrequency (RF) electrode. Methods: Metal implants models were established in seven in-vitro porcine livers using silver clips or 125I seeds. RFA were conducted centering the RF electrode axis1 cm away from them, with one side containing a metal implants model the test group and the other side the control group. The thermometric needles were used to measure multi-point temperatures in order to compare the time-distance-temperature difference between the two groups. The gross scopes of the ablation of the two groups were measured and the tissues were analyzed for microscopic histology. Results: At the ablation times of 8, 12,and 15 min, the average multi-point temperatures of the test group and the control group were 48.2+/-18.07[degree sign]C, 51.5+/-19.57[degree sign]C, 54.6+/-19.75[degree sign]C, and 48.6+/-17.69[degree sign]C, 52.2+/-19.73[degree sign]C, 54.9+/-19.24[degree sign]C, respectively, and the differences were not statistically significant (n=126, P>0.05). At the ablation times of 12 and 15 min, the ablation scopes of the test group and the control group were (horizontal/longitudinal diameter) 1.55/3.48 cm, 1.89/3.72 cm, and 1.56/3.48 cm, 1.89/3.72 cm, respectively, and the differences were not statistically significant (n=14, P>0.05). The two groups had the same manifestations in microscopy. Conclusions: Metal implants do not cause significant thermal effect on RFA.

via World Journal of Surgical Oncology