Pancreatitis-associated collections are classified by timing, maturity, and content: fluid-only versus necrotic debris. --- ### Revised Atlanta Framework | Timing / Content | Interstitial Edematous Pancreatitis | Necrotizing Pancreatitis | |---|---|---| | <4 weeks | Acute peripancreatic fluid collection | Acute necrotic collection | | ≥4 weeks / mature wall | Pseudocyst | Walled-off necrosis | --- ### Practical Distinctions #### Acute Peripancreatic Fluid Collection Early, fluid-only collection without mature wall. #### Pseudocyst Mature, encapsulated, fluid-only collection, usually after interstitial pancreatitis. #### Acute Necrotic Collection Early collection containing variable fluid and necrotic debris. #### Walled-Off Necrosis Mature, encapsulated necrotic collection, usually after necrotizing pancreatitis. --- ### Management Principle Intervention is driven by symptoms, infection, obstruction, nutritional failure, or persistent clinical deterioration — not imaging appearance alone. --- ### Related Pages - [[Acute Pancreatitis]] - [[Necrotizing Pancreatitis]] - [[Pancreatic Cysts]] - [[Step-Up Approach]]