Acute pancreatitis: Structured report template of magnetic resonance imaging

Table 1 Magnetic resonance imaging sequences and parameters (1.5 Tesla) for acute pancreatitis

Sequence	Repetition time (ms)	Echo time (ms)	Slice thickness (mm)	Slice space (mm)	Matrix	Field of view (mm)	Flip angle
T1WI	6.19	2.86	2.4	0	143 × 272	300 × 400	15°
IP/OP	6.19	4.47	2.4	0	143 × 272	300 × 400	15°
T2WI	2000	78.26	5	1	256 × 152	300 × 380	150°
DWI	3611	64	6	1.2	114 × 144	300 × 380	90°
MRCP	6500	1004	60	60	336 × 336	340 × 340	160°
DCE MRI	6.19	2.86	2.4	0	143 × 272	300 × 400	15°

IP/OP: In-phase/Out-of-phase; DWI: Diffusion-weighted imaging; MRCP: Magnetic resonance cholangiopancreatography; DCE: Dynamic contrast-enhancement.

Table 2 Magnetic resonance imaging sequences and parameters (3.0 Tesla) for acute pancreatitis

Sequence	Repetition time (ms)	Echo time (ms)	Slice thickness (mm)	Slice space (mm)	Matrix	Field of view (mm)	Flip angle
T1WI	3.91	1.42	4.5	0	304 × 274	400 × 300	12°
T2WI	8963	116.16	6	20	256 × 218	380 × 300	90°
DWI	3555	63.8	6.0	20	128 × 101	380 × 300	90°
MRCP	6000	753.6	60	0	368 × 276	300 × 300	180°
DCE MRI	3.91	1.42	4.5	0	304 × 274	400 × 300	12°

DWI: Diffusion-weighted imaging; MRCP: Magnetic resonance cholangiopancreatography; DCE: Dynamic contrast-enhancement.

Table 3 Structured report template of magnetic resonance imaging for acute pancreatitis

Contents	Descriptions
Pancreas itself
Enlargement	Diffuse; Focal (head/neck/body/tail)
Edge	Clear; blur
Signal intensity	Variable owing to internal necrosis and/or hemorrhage
Enhancement	Homogeneous; Heterogeneous
Pancreatic duct	Normal; dilated (mm); stricture (mm); calculi (mm)
Pancreatic necrosis
Position	Head; neck; body; tail
Range1	< 30%; 30%-50%; > 50%
Peripancreatic changes
Renal fascia and peritoneum	Thickening (anterior renal fascia/posterior renal fascia/lateral cone fascia/lateral abdominal wall peritoneum); Enhanced or not?
Peripancreatic fat space	Clear; Blur
Peripancreatic fat necrosis	Site (retroperitoneal space/transverse colonic mesentery/small intestinal mesentery); amount (patchy/large flake); whether combined with hemorrhage (fat-suppressed T1-hyperintense)[21]
Peripancreatic collection	Position2; volume (linear/patchy/large); encapsulated round/oval; contents (homogeneous fluid signal/heterogeneous mixed signal)
Local complication
I Pancreatic/peripancreatic collection (type)	Some of the features can be seen in the above peripancreatic collection
APFC	Yes or no?
ANC	Yes or no?
Pseudocyst	Yes or no? If yes, thickness of the cyst wall (mm, uniform?); Is adjacent to and pushing out adjacent organs (stomach/duodenum, etc.)?
WON	Yes or no? If yes, thickness of the lesion wall (mm); Whether the wall is enhanced and the pattern of enhancement? “Non-liquid substances” within WON (< 10%, 10%-40%, > 40%)[23]; Is WON close to adjacent organs (stomach/duodenum/AC/DC)?
II Infection of collection	Suggestive signs [bubble sign, air-fluid level sign]
Complicated intestinal fistula	Relationship between collection and the intestinal fistula canal, and the intestinal segment of intestinal fistula (duodenum/AC/DC)
III Pancreatic duct disruption syndrome	Site (head/neck/body); Is MPD dilated on the upstream/caudal side of the interruption (mm)? Relationship with adjacent pseudocyst/WON?
IV Vascular complications
Venous thrombosis	SV; SMV; PV, etc.
Sinistral portal hypertension	Establishment of collateral vascular network3
Pseudoaneurysm	Size (mm) and involvement artery4
Organ complications
Liver	Fatty liver (Signal difference of liver in the in-phase and out-of-phase)
Gallbladder and bile duct	Gallbladder stones (sandy/granular/filled); Common bile duct stones (site, number, size) and maximum duct diameter (mm)
Lung	Extent of pneumonia, pleural effusion
Subcutaneous and intermuscular space	Edema/effusion
Severity image score (MRSI)	(0-10) score
Comparison with previous imaging findings	For AP review, describe the pancreatic/peripancreatic changes after treatment; for surgical treatment, describe the site of the external drainage tube and internal covered metal stent

¹The ratio of the area of pancreatic necrosis in the largest slice to the whole pancreatic area.

²Sites of effusion include: left/right pararenal anterior spaces, perirenal spaces, posterior pararenal spaces, omental sac, bilateral paracolic sulcus, transverse colonic mesentery, small intestinal mesentery, greater omentum, other abdominal spaces, pelvic extraperitoneal spaces, pelvis cavity, thoracic cavity, and mediastinum.

³Such as left/right gastric omental vein, gastrocolic trunk, short gastric vein, submucosal vein of gastric fundus and gastric coronary vein).

⁴Such as splenic artery, pancreaticoduodenal artery, gastroduodenal artery, superior mesenteric artery, and celiac trunk. APFC: Acute peripancreatic fluid collection; ANC: Acute necrotic collection; WON: Walled-off necrosis; AC: Ascending colon; DC: Descending colon; MPD: Main pancreatic duct; SV: Splenic vein; SMV: Superior mesenteric vein; PV: Portal vein; IEP: Interstitial edematous pancreatitis; ANP: Acute necrotizing pancreatitis.