CT findings and grading of acute pancreatitis (CT severity index [CTSI])

Grading based upon findings on unenhanced CT
Grade	Findings	Score
A	Normal pancreas - normal size, sharply defined, smooth contour, homogeneous enhancement, retroperitoneal peripancreatic fat without enhancement	0
B	Focal or diffuse enlargement of the pancreas, contour may show irregularity, enhancement may be inhomogeneous but there is no peripancreatic inflammation	1
C	Peripancreatic inflammation with intrinsic pancreatic abnormalities	2
D	Intrapancreatic or extrapancreatic fluid collections	3
E	Two or more large collections of gas in the pancreas or retroperitoneum	4
Necrosis score based upon contrast-enhanced CT
Necrosis (%)		Score
0		0
<33		2
33-50		4
≥50		6

CT severity index equals unenhanced CT score plus necrosis score: maximum = 10, ≥6 = severe disease.

CT: computed tomography.

Adapted from: Balthazar EJ, Robinson DL, Megibow AJ, Ranson JH. Acute pancreatitis: value of CT in establishing prognosis. Radiology 1990; 174:331.

Graphic 68191 Version 3.0