To detect and characterize focal pancreatic lesions
- Scout (multiple planes)
- T2 weighted Axial with fat suppression
- Axial DWI (b=1000)
- Axial DUAL ECHO IN/OUT PHASE GRE
- Coronal MRCP with RES[IRATORY TRIGGER
- T1 out of phase Spoiled Gradient Echo (SGE) Axial
- T1 in phase SGE Axial with fat suppression
- T1 In Phase FLASH Axial with fat suppression at :-
- End of saline flush
- 45 seconds post contrast
- 1.5 minutes post contrast
- Cor Fat-sat Gad
NOTE:Pancreatic carcinoma appears with low signal on unenhanced fat suppressed T1 images, but a tumour may be mimicked by age related changes. Immediately post contrast, the normal pancreas enhances avidly leaving the pancreatic carcinoma as a low signal region. Normal pancreatic enhancement drops off rapidly.
Pancreas MRI Technical notes
Normal pancreas on unenhanced T1-weighted images has intermediate signal intensity--similar to liver--and is hypointense to surrounding fat. With T1-weighted fat-saturation, the pancreas becomes the highest-signal structure in the upper abdomen and is readily detectable. On nonenhanced T2-weighted images, the normal pancreas is iso- or hyperintense to liver. The pancreatic duct and common bile duct within the head of the pancreas exhibit very high signal on T2-weighted images. 2,24 Regarding contrast dynamics, after bolus gadolinium-based contrast injection, the pancreas enhances before the liver. As in liver imaging, dynamic image acquisition is important for improved pancreatic lesion detection, characterization, and differential diagnosis. Unenhanced fat-suppressed T1-weighted and immediate (arterial) fat-suppressed T1-weighted post-contrast images are by consensus the most useful for diagnosis of pancreatic disease. 25,26 In general, it is the aqueous content of the normal pancreas that creates high signal on T1-weighted images. Pancreatic tumors and chronic pancreatitis contain less aqueous tissue than normal pancreas, leading to their characteristically low signal intensity
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