Clinical impact of MR cholangiopancreatography in patients with biliary disease.

PURPOSE: To evaluate the role of MR Cholangiopan-creatography (MRCP) as a first imaging modality in patients with suspected biliary tree pathology and indications to endoscopic retrograde cholangiopancreatography (ERCP). MATERIAL AND METHODS: Eighty-eight patients, with clinical signs of biliary tree pathology underwent MRCP, performed with a 1.5 T unit and a phased-array coil. Surgery, intraoperative cholangiography, percutaneous transhepatic cholangiography (PTC) or ERCP were regarded as the gold standard in patients with obstruction; the remaining patients underwent follow-up MRCP examinations at 6-9 months. The MR examination was performed with baseline T1w 2D FLASH and T2w TSE sequences, followed by the MRCP study (single-slab breath-hold RARE and multislice breath-hold HASTE sequences). The MR images were independently evaluated by two radiologists. RESULTS: MRCP showed normal findings in 20 patients; 68 patients had biliary duct dilatation. In 11 out of 68 patients MRCP did not identify any obstruction (9/11 were true negative cases). A diagnosis of benign obstruction was expressed in 36/59 patients (4 chronic pancreatitis, 29 choledocolithiasis, 4 inflammatory obstruction, 2 primary sclerosing cholangitis), with 1 false positive and 5 false negatives (sensitivity, specificity and diagnostic accuracy of 86%, 95% and 90%, respectively). MRCP identified 23 neoplastic stenoses (20/23 were true positives): the sensitivity, specificity and diagnostic accuracy values were 100%, 87% and 95%, respectively. MRCP correctly identified the level of obstruction in 100% of cases. CONCLUSIONS: MRCP may be considered as a first-step imaging method in patients with clinical signs of biliary disease. The workload of ERCP in the diagnostic stage could therefore be reduced and its use be reserved for therapeutic indications.