Pancreatitis: Preventing catastrophic haemorrhage

Table 3 Defining pancreatic and peri-pancreatic collections

Acute peri-pancreatic fluid collection	Don not have well defined walls
	Homogenous, confined to normal fascial planes in retroperitoneum
	May be multiple
	Likely to develop into a pseudocyst if they persist > 4 wk
Pancreatic pseudocyst	Fluid collection in peri-pancreatic tissues
	Occasionally partly/totally intra-pancreatic
	Well defined wall with essentially no solid material
	Occur typically after 4 wk
Acute necrotic collection	Fluid collection within the first 4 wk containing necrotic tissue and fluid.
	Presence of necrosis differentiates it from APFC
Walled off necrosis	Necrotic tissue contained within an enhancing wall of reactive tissue
	Usually occurs > 4 wk after the onset of necrotising pancreatitis
Infected necrosis	Presence of gas within collection
	Positive cultures post FNA

APFC: Acute peri-pancreatic fluid collection.