The waterjet necrosectomy device for endoscopic management of pancreatic necrosis: design, development, and preclinical testing (with videos)

Abstract

Endoscopic intervention has emerged as a first-line option for management of symptomatic pancreatic necrosis, yet endoscopic debridement is limited by the lack of dedicated endoscopic tools intended for this purpose. The objectives of this study were to design and build a prototype necrosectomy device compatible for use with a flexible endoscope and capable of selective tissue fragmentation, and to test the prototype in benchtop and porcine models. A novel prototype, named the waterjet necrosectomy device (WAND), was designed and developed, consisting of a single-use disposable endoscopic waterjet instrument capable of waterjet selection and independent tip articulation while fitting through a 2.8-mm working channel of a standard adult upper GI endoscope. Benchtop, exvivo, and invivo (porcine) testing was performed in the initial stages of investigation. The WAND was capable of delivering a continuous waterjet force with a surface pressure of 0.72 bar at a flow rate of 0.37 L/minute. In phase 1 of testing, the WAND was able to achieve complete fragmentation of gelatin as a surrogate for pancreatic necrosis in benchtop testing. In phase 2 of testing, the WAND was able to achieve complete fragmentation of freshly explanted human pancreatic necrosis. In phase 3 of testing for safety in fresh necropsy swine, use of the WAND resulted in no significant tissue trauma, even when irrigation was applied at closer proximity and for more extended duration than would be anticipated in clinical use. The WAND prototype delivers irrigation capable of fragmenting necrotic debris exvivo and avoiding trauma to healthy nontarget tissue. Planning is underway for first-in-human studies to assess the efficacy and safety of the WAND for endoscopic pancreatic necrosectomy.