Endosonographic drainage of pancreatic fluid collections and walled-off necrosis

Endosonographic drainage of pseudocysts and walled-off necrosis (WON) has not been standardized. Drainage of pseudocysts via endosonographic guidance has high rates of technical success via the transmural approach. Alternative modalities including transpapillary endoscopic retrograde pancreatography with pancreatic duct sphincterotomy and pancreatic duct stent placement are options for patients with small pseudocysts and in the presence of pancreatic duct disruption. Drainage of WON has a variety of approaches and may require a combination of endoscopic or percutaneous techniques to achieve the optimal outcome. Endosonographic drainage of WON has lower rates of mortality and morbidity compared to surgical intervention. Several options regarding stent placement exist including the use of fully covered self-expandable metal stents and lumen-apposing metal stents. Depending upon their properties, each type of stent carries its own risk including the risk of migration. The endoscopist performing drainage of these fluid collections must take into account the number and size of these collections as well as the presence and amount of necrotic debris in order to choose the most appropriate technique and equipment in order to achieve optimal outcomes.