Abstract
Radiofrequency ablation requires accurate probe placement using ultrasound guidance. The purpose of this study was to develop an in vivo tumor-mimic model for learning open and laparoscopic radiofrequency ablation. Tumor-mimics were created in ex vivo porcine livers by injecting a mixture of 3% agarose, 3% cellulose, 7% glycerol, and 0.05% methylene blue, which formed 1 cm hyperechoic, discrete lesions on ultrasound. Open and laparoscopic (using a box-trainer) ablation techniques were practiced. In vivo experiments were then conducted in 10 pigs. Three tumor-mimics were created in each animal using a laparoscopic approach. Lesions were characterized sonographically, ablated using an open (n = 5) or laparoscopic (n = 5) approach, and examined pathologically. An ablation in normal liver tissue was performed as a control. Tissue impedance was recorded. Target creation took 81 minutes per animal and 96% of injections were successful. Tissue impedance (48.8 ±5.8 vs. 49.6 ±5.4) and ablation size (25.1 ±3.4 vs. 24.3 ±5.1) were not significantly different for controls (n = 8) and tumor-mimics (n = 26), respectively. One animal died of a pulmonary embolism following injection of agarose into a hepatic vein. The agarose-based tissue-mimic creates realistic sonographic targets for learning ultrasound-guided open and laparoscopic radiofrequency ablation in an in vivo model.
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Funding was provided by the Southwestern Center for Minimally Invasive Surgery as supported in part by an educational grant from United States Surgical—A Division of Tyco Healthcare Group.
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Scott, D.J., Young, W.N., Watumull, L.M. et al. Development of an in vivo tumor-mimic model for learning radiofrequency ablation. J Gastrointest Surg 4, 620–625 (2000). https://doi.org/10.1016/S1091-255X(00)80112-2
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DOI: https://doi.org/10.1016/S1091-255X(00)80112-2