The breath-hold 2D MRCP and the respiratory-triggered 3D MRCP sequences, comparative study as regards the possible pitfalls.

This study aims to clarify the common pitfalls, frequently seen in different MRCP sequences. Patients and methods 200 patients were evaluated with (T2_TSE_Cor_BH) thick slab (group A) and (3D-MRCP HR) thin slab sequences (group B), in correlation with routine MRI, CT scan and ERCP. Results Partial volume overlap pitfalls were noted in 16 patients (8%) in group A. Little bile pitfalls in 4 (2%) in each group, ampullary stones pitfalls in 3 (1.5%) group A, one (0.5%) in group B, respiratory motions pitfalls in 11 (5.5%) group A. Vascular impression pitfalls in 9 (4.5%) group A, two (1%) in group B, and cystic duct-CBD junction pitfalls 2 (1%) in group A. Sphincter of Oddi contraction pitfalls 3 (1.5%) and Pneumobilia pitfalls 2 (1%) in each group. ERCP was the standard reference in this study, with calculated 80% sensitivity and 80% specificity of group A, compared to group B images which were 95.7% and 88% respectively. Conclusion Many pitfalls could be encountered in MRCP, with resultant false judgment. So it should be carefully monitored with revisions of the source images, MRI and CT if needed, by the radiologist. Also, full past history is required before the final radiological conclusion. [ABSTRACT FROM AUTHOR]