Contrast-enhanced MRI combined with MR cholangiopancreatography for the evaluation of patients with biliary strictures: differentiation of malignant from benign bile duct strictures.
OBJECTIVE
To determine imaging criteria for the combined use of contrast-enhanced (CE)-MRI and MR cholangiopancreatography (MRCP) to differentiate malignant from benign biliary strictures.


METHODS
A total of 44 patients with biliary stricture who had undergone unenhanced, MRCP, and dynamic MRI were identified from radiological and surgical databases. Two radiologists analyzed MR features for asymmetry, luminal irregularity, abrupt narrowing, outer margin, signal intensity (SI) on T2-weighted (T2W) images, and hyperenhancement relative to liver parenchyma during portal phase. The wall thickness and length of the narrowed segment were measured. MR findings relevant as predictors were identified using a Chi-square or Fisher's exact test and the odds ratio (OR).


RESULTS
The presence of hyperenhancement relative to liver parenchyma, length > 12 mm, wall thickness > 3 mm, indistinct outer margin, luminal irregularity, and asymmetry of strictured bile duct were significant factors for malignancy (P < 0.05). Malignant strictures were significantly thicker (5.0 +/- 2.0 mm) and longer (27.0 +/- 13.6 mm) than benign strictures. When any three or more of these six criteria were used in combination, we could identify 100% of malignant strictures and 87.0% of benign strictures.


CONCLUSIONS
The combined use of CE-MRI and MRCP helped to define the criteria for differentiating malignant from benign biliary strictures in our data.
Kim
Ji Yang
JY
Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.
Lee
Jeong Min
JM
Han
Joon Koo
JK
Kim
Se Hyung
SH
Lee
Jae Young
JY
Choi
Jin Young
JY
Kim
Soo Jin
SJ
Kim
Hyuck Jung
HJ
Kim
Ki Hyeun
KH
Choi
Byung Ihn
BI
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001649:Bile Duct Diseases / Q000175:diagnosis* / Q000473:pathology; D001652:Bile Ducts / Q000473:pathology*; D001660:Biliary Tract Diseases / Q000175:diagnosis* / Q000473:pathology; D049448:Cholangiopancreatography, Magnetic Resonance / Q000379:methods*; D002779:Cholestasis / Q000473:pathology; D003287:Contrast Media / Q000494:pharmacology; D005260:Female; D006801:Humans; D008099:Liver / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged
D003287:Contrast Media