EUS-guided Nd:YAG laser ablation of normal pancreatic tissue: a pilot study in a pig model

Background: Laser ablation with a neodymium:yttrium aluminum garnet (Nd:YAG) laser can achieve a high rate of complete tissue necrosis and has been applied as a minimally invasive, palliative option in hepatocellular carcinoma, liver metastasis in colorectal cancer, and malignant thyroid nodules. Objective: To assess the in vivo feasibility of EUS-guided laser ablation with an Nd:YAG laser of normal pancreatic tissue of a porcine model. Design: Prospective investigation. Setting: Hospital animal laboratory. Subjects: Eight pigs. Interventions: EUS-guided puncture of the pancreatic tail with a laser-beam fiber. An Nd:YAG laser (1.064 nm) was used, with an output power of 2 and 3W and a total delivered energy of 500 and 1000 J in continuous mode. Main Outcome Measurements: The 24-hour follow-up of the pigs was focused on clinical and laboratory aspects. Results of histological studies of the pancreas were obtained 24 hours after the procedure on necroscopy tissue. Results: There were no technical limitations to the performance of the procedure. Tissue necrosis, localized in the pancreatic parenchyma, was observed in all animals on histological examination. The volume of ablation tissue ranged from a mean of 314 mm(3) to 483 mm(3). The ablation area ranged from a mean of 49 mm(2) to 80 mm(2). No major postprocedure complications were recorded, and all the pigs survived at 24 hours. Limitation: Animal study. Conclusions: EUS-guided laser ablation of the pancreas with an Nd:YAG laser is feasible in a porcine model. (Gastrointest Endosc 2010;72:358-63.)