Acute pancreatitis — CT (modified CTSI)

CTModified CTSI (Mortele 2004)

Severity assessment of acute pancreatitis on contrast-enhanced CT.

Applies to

Acute pancreatitis on contrast-enhanced CT, typically >72 hours after onset

Does not apply to

Chronic pancreatitis without an acute episode
Very early scans (<72 h), which underestimate necrosis

What to report

Tap an item to check it off while dictating.

1.Parenchymal enhancement / necrosis
Non-enhancing parenchyma indicates necrosis; estimate the percentage. Necrosis is best assessed after 72 hours.
Pitfall: CT within 72 hours of onset can substantially underestimate necrosis.
2.Peripancreatic collections
Classify by revised Atlanta terms and timing: APFC and pseudocyst (non-necrotic); acute necrotic collection (ANC) and walled-off necrosis (WON) after ~4 weeks.
3.Extrapancreatic findings
Pleural effusion, ascites, and involvement of adjacent organs or the GI tract.
4.Vascular complications
Splenic or portal vein thrombosis and pseudoaneurysm (splenic/gastroduodenal arteries).
Pitfall: A pseudoaneurysm is a source of potentially fatal hemorrhage — flag it explicitly.
5.Biliary cause
Look for gallstones or choledocholithiasis and biliary dilatation as an etiology.

Scores & calculators

Modified CT severity index

Modified CTSI (Mortele 2004)

Severity of acute pancreatitis on contrast-enhanced CT.

Pancreatic inflammation

Normal pancreas+0Intrinsic abnormality ± peripancreatic fat stranding+2Peripancreatic fluid collection or fat necrosis+4

Pancreatic necrosis

None+0≤ 30%+2> 30%+4

Extrapancreatic complications

None+0One or more (pleural effusion, ascites, vascular or GI involvement, parenchymal complication)+2

Complete the inputs to see the result.

Sources

Modified CT severity index — Mortele KJ et al. AJR (2004)
Revised Atlanta classification — Banks PA et al. Gut (2013)

Content review: Content pending clinical review · 2026-07-09

Educational reference for trained clinicians. Verify every result against the cited original guideline before use. Not a substitute for clinical judgment or medical advice.