Development of a perfused ex vivo tumor-mimic model for the training of laparoscopic radiofrequency ablation

Background: Laparoscopic radiofrequency ablation (RFA) is a safe and effective method for tumor destruction in patients with unresectable liver tumors. However, accurate probe placement using laparoscopic ultrasound guidance is required to achieve complete tumor ablation. This study aimed to develop a perfusable ex vivo tumor-mimic model for laparoscopic radiofrequency ablation training. Methods: After rinsing the prepared liver vessels with anticoagulants, porcine livers were perfused. Tumor-mimics were created by injecting a mixture consisting of 3% agarose, 3% cellulose, 7% glycerol, and 0.05% methylene blue, creating hyperechoic lesions in ultrasound. Heparinized porcine blood was used as perfusion medium. Continuous perfusion of the porcine liver was provided by connection of a pump system to the portal vein and the vena cava inferior. Laparoscopic RFA techniques were taught using a laparoscopic pelvi-trainer. Results: A total of 30 laparoscopic ablations were performed in four porcine livers. The simulated "tumors'' were clearly visible on laparoscopic ultrasound and not felt during placement of the RFA probe. In addition, color duplex ultrasound showed clear signals indicating for a sufficient liver perfusion. Conclusion: Laparoscopic RFA requires advanced laparoscopic ultrasound skills for an accurate placement of the RFA probe. The perfused tumor-mimic model presented is a safe, easy, effective, and economic method to improve and train laparoscopic RFA skills on porcine liver tissue.