Endoscopic Interventions in Acute Pancreatitis: What the Advanced Endoscopist Wants to Know.

Endoscopic interventions play an important role in the modern management of pancreatic fluid collections. Successful management of pancreatitis is dependent on proper classification of the disease and its local complications. The 2012 revised Atlanta classification divides acute pancreatitis into subtypes of necrotizing pancreatitis and interstitial edematous pancreatitis (IEP) on the basis of the radiologic presence or absence of necrosis, respectively. Local complications of IEP include acute pancreatic fluid collections and pseudocysts, which contain fluid only and are differentiated by the time elapsed since the onset of symptoms. Local complications of necrotizing pancreatitis include acute necrotic collections and walled-off necrosis, which contain nonliquefied necrotic debris and are differentiated by the time elapsed since the onset of symptoms. Endoscopic techniques are used to treat local complications of pancreatitis, often in a step-up approach, by which less invasive techniques are preferred initially with potential subsequent use of more invasive procedures, dependent on the patient's clinical response and collection evolution. Common interventions performed by the advanced endoscopist include endoscopic transmural drainage and endoscopic transmural necrosectomy. However, some collections require a multimodal approach with adjunctive placement of percutaneous drainage catheters or the use of videoscopic-assisted retroperitoneal débridement. Additional endoscopic interventions may be required in the setting of pancreatic or biliary duct stones or strictures. Common complications of endoscopic intervention in the setting of pancreatitis include bleeding, infection, perforation, and stent migration. This article reviews the classification of acute pancreatitis, familiarizes radiologists with the common endoscopic techniques used in its management, and improves identification of the clinically relevant imaging findings and procedural complications related to endoscopic interventions in pancreatitis. © RSNA, 2018.