Recognition and Importance of New Definitions of Peripancreatic Fluid Collections in Managing Patients with Acute Pancreatitis

Our understanding of the etiopathogenesis of acute pancreatitis has matured tremendously in the last 3 decades. Advanced cross-sectional imaging with 3-dimensional techniques along with use of intravenous contrast to image the presence or absence of organ tissue perfusion has allowed early recognition of necrotizing pancreatitis. With this knowledge, the old terms to describe what used to be called 'peri-pancreatic fluid collections' we now recognize are no longer accurate nor appropriate. The 2013 revised Atlanta Classification has introduced a new, accurate, objective classification of acute pancreatitis and terminology for the natural history of all forms of acute pancreatitis that is easy to use and will help in both the description of the disease and its appropriate treatment. This review will describe these pancreatic and peri-pancreatic collections with added insight into their natural history.