CT and MRI studies of 46 patients with verified pancreatic tumors accompanied by MPD dilatation were analyzed.
Percentage of observed tumors: ductal adenocarcinoma - 39 (85%),
intraductal papillary mucinous tumor MD - 4 (9%),
intraductal papillary mucinous tumor BD - 1 (2%),
lymphoma - 2 (4%).
The studies were performed on a 64-detector CT scanner and 1.5T MRI +MRCP,
with intravenous contrast media using a protocols according to NCCN Guidelines 2.2016.
Estimation criteria:
- the presence or absence of the point of obstruction of the duct (abrupt cutoff, amputation of the rift)
- diameter of the duct expansion
- diameter in comparison to the size of the tumor
- equability of the expansion and the gradient (upstream dilatation)
- dilatation of branch-ducts
- the protrusion of duodenal papilla
- the densitometric and signal characteristics of the contents in the expanded duct.
In all ductal adenocarcinoma cases (n 39/100%),
point of obstruction of the MPD with a sharp rift break was observed.
The degree of dilatation was significant even for tumors of small (<2 cм T1 stage n 4/10% ) and was d 5 to 14 mm.The expansion was equal with a gradient increase to the level of the point of obstruction (abrupt cutoff with upstream dilatation)(Fig.3).
A peculiarity was that even with significant expansion of the main duct, the side ducts were not expanded (Fig.4).
The densitometric and signal characteristics of the contents in the expanded duct were similar to water.
IPMN-MD was with extremely dilated pancreatic duct, but the point of obstruction was not detected.
Fusiform duct expansion increased to larger sizes 35 mm (n 2/50%),
without gradient (Fig.
5).
Сonversely,
the duct was traced to the duodenal papilla with protrusion (Fig.
6).
The presence of a grape-like dilatation of branch-ducts with mucin content (which is best shown on heavily T2WI) (Fig.2,
Fig.
7).
With IPMN-BD,
heavily T2WI (T2W_spc) and MRCP exellently shows a direct communication between BD cluster and MPD,
without the point of obstruction (Fig.
8).
BD was expanded only in the affected area,
with mucin clots.
With lymphoma,
was a very small MPD expansion (up to 4-5 mm) in comparison to the large size of the tumor (>4 cm).
Narrowed duct in the tumor without a point of obstruction (Fig.
9,
Fig.
10). The densitometric and signal characteristics of the contents in the expanded duct were similar to water.