Comparison of ablation performance between dual internally cooled wet tip and conventional dual internally cooled tip radiofrequency electrodes: an experimental study in ex vivo bovine liver

Abstract

Objective: To evaluate the performance of dual internally cooled wet tip (ICWT) radiofrequency electrodes in comparison to dual internally cooled tip (ICT) electrodes. Methods: Twenty ablation zones were created for each type of electrodes. Planned procedure time was 6 min. Diameters of the ablation zone along the x-, y-, and z-axes (Dx, Dy, and Dz), ablation zone sphericity, quantitative sphericity measurement, and ablation volume were measured and compared between the two electrode types. Circularity of the ablation zone on the surface with x-and z-axes (zx plane) and amount of energy applied were also compared. Results: Dx and Dz were significantly longer with ICWT than those with ICT (Dx: 3.0 vs. 2.8 cm, p ¼ .018; and Dz: 2.7 vs. 2.3 cm, p < .001, respectively). Dy was not significantly different (3.0 vs. 2.9 cm, p ¼ .220). Moreover, 85% (17/20) and 30% (6/20) of ablation zones from ICWT and ICT were spherical (p ¼ .001), respectively. Quantitative measurement showed that ICWT was more spherical compared to ICT (0.962 vs. 0.881, p ¼ .001). The ablation volume was also significantly higher with ICWT (11.55 vs. 9.45 cm3, p ¼ .003). The ablation zone on the zx plane was more circular with ICWT (0.907 vs. 0.883, p ¼ .028). The amount of energy applied was significantly bigger with ICWT (18508 vs. 16998 WS, p ¼ .003). Conclusion: Dual ICWT electrodes were better able to create more spherical and larger ablation zones than dual ICT electrodes.

Percutaneous radiofrequency ablation of hepatocellular carcinoma in a recent cohort at a tertiary cancer center: incidence and factors associated with major complications and unexpected hospitalization events

“…Dz refers to the longest vertical diameter from the coronal or sagittal images. c) The ablation volume was calculated using the following formula: ablation volume=π(Dx×Dy×Dz)/6 [8]. Ultrasonography 42(1), January 2023 e-ultrasonography.org cm in a recent cohort at a tertiary cancer center.…”

“…Dz refers to the longest vertical diameter from the coronal or sagittal images. b) The ablation volume was calculated using the following formula: ablation volume=π(Dx×Dy×Dz)/6 [8]. diameter on the axial section of the post-RFA CT) was significantly larger in the major complication group than in the no major complication group (P=0.023).…”

“…Meanwhile, with technical developments, RFA has been performed using perfusion electrodes or multiple electrodes to produce larger ablation zones [ 7 , 8 ]. In addition, no-touch RFA has recently been implemented, which offers better local tumor control by effectively producing sufficient ablative margins without puncturing the tumor through the insertion of multiple electrodes around it [ 9 , 10 ].…”

Percutaneous radiofrequency ablation near large vessels in beagle livers: the impact of time and distance on the ablation zone

“…Furthermore, a full three-dimensional characterization of the ablation (i.e., calculation of the ablation volume) was not performed because of the irregular shape of the ablation zone. The commonly used ellipsoid volume formula [18,26] may overestimate the ablation zone; however, new software measurement technologies may facilitate more accurate volume calculations. Finally, blood flow and actual RF energy deposition, which are key to the quantification of heat sinking, were not explicitly measured.…”

Percutaneous radiofrequency ablation of solitary hepatic metastases from colorectal cancer: risk factors of local tumor progression-free survival and overall survival

“…The maximum (Dmax) and minimum (Dmin) diameters of the ablation zone were measured from axial CT images of the portal phase and the longest vertical diameter (Dv) from sagittal or coronal images. The ablation volume was calculated by the formula for ellipsoid lesion (ablation volume=π(Dmax×Dmin×Dv)/6) [ 17 ].…”