Transpapillary endopancreatic surgery: decompression of duct system and comparison of greenlight laser with monopolar electrosurgical device in ex vivo and in vivo animal models.

BACKGROUND: Endopancreatic surgery (EPS) is an experimental minimally invasive technique for resection of pancreatic tissue from inside the pancreatic duct, accessed via the duodenum and papilla. It is proposed as an alternative to duodenum-preserving pancreatic head resection in benign diseases such as chronic pancreatitis (CP). This study evaluated the use of EPS for resection of pancreatic duct stenoses. Moreover, greenlight laser (GLL) and monopolar electrosurgical device (MES) were compared as resection tools for EPS.

METHODS: The suitability of EPS for resection of stenoses was evaluated in ex vivo bovine pancreas (n = 8). Artificially created stenoses in the pancreatic head were accessed via the duodenal papilla and resected from inside the organ with MES through a rigid endoscope. Furthermore, standardized pancreatic resections were performed in an in vivo porcine model using either GLL (n = 18) or MES (n = 18) to compare blood loss, operating time, and complications. Thermal damage to the surrounding tissue was assessed using a standardized histological classification.

RESULTS: Stenosis resection by EPS was feasible in 8/8 bovine pancreases, with a procedure time of 17 (12-24) min. No perforation of the organ occurred. Resection by GLL was associated with reduced blood loss [median 1.7 (interquartile range 0.6-2.6) ml vs. 5.1 (3.8-13.2) ml; p < 0.01] and shorter operating time [109 (81-127) s vs. 390 (337-555) s; p < 0.01] compared with MES. The zone of thermal tissue damage was more extensive when using GLL than with MES [4.12 (3.48-4.89) mm vs. 1.33 (1.09-1.48) mm; p < 0.01].

CONCLUSION: Transduodenal-transpapillary EPS can be used to resect stenoses and decompress the pancreatic duct system. Both GLL and MES are feasible resection methods for EPS. However, GLL showed better hemostatic characteristics than MES in an in vivo porcine model. Safety measures such as temperature control and image-guided navigation should be employed to monitor the resection and tissue heating.