<prompt> Confluent areas of pancreatic parenchyma that do not demonstrate enhancement after the administration of intravenous IV contrast material is known as:Pseudocystwalled off pancreatic necrosisAcute peripancreatic fluid collectionPancreatic necrosis  <response>: Pancreatic necrosis is defined as confluent areas of pancreatic parenchyma that do not demonstrate enhancement after the administration of IV contrast material. Pseudocyst is with a well defined wall with fluid inside. Walled off pancreatic necrosis happens after 4 weeks of acute pancreatic necrosis. Acute peripancreatic fluid collection is outside the pancreas. Ref: ACR Appropriateness Criteria,Acute Pancreatitis. 