This is a retrospective chart review study examining 1) demographic data such as age, sex, etiology of pancreatitis 2) clinical data including radiological characteristics of walled off pancreatic necrosis, walled off necrosis related admissions and readmission following endoscopic drainage, surgical or percutaneous procedures performed for the management of walled off pancreatic necrosis, and clinical outcomes following treatment of WON (including hospital readmissions, WON resolution, procedure complications, WON related death) 3) endoscopy data including indication for initial endoscopic drainage and subsequent endoscopic procedures performed for management of walled off necrosis (including additional EGD's, endoscopic drainage procedures, and/or necrosectomy)

Inclusion Criteria:

• Patients over 18 years of age who underwent endoscopic drainage of walled off pancreatic necrosis
• Patients who did not require further intervention (either surgical, percutaneous, or endoscopic) following endoscopic drainage
• Patients who required further intervention for walled off pancreatic necrosis (either surgical, percutaneous, or endoscopic) following endoscopic drainage.
• Patients who underwent percutaneous or surgical interventions prior to endoscopic drainage

Exclusion Criteria:

• Pancreatic pseudocysts without any solid debris
• Under 18 years of age at the time of endoscopic drainage

Patients with organized collections that contain both solid and liquid debris and arise from necrotizing pancreatitis, referred to as walled off pancreatic necrosis (WON)