Evaluation of MRI Sequences for Ultra-rapid Acquisition of Bile Ducts Images

The Institute of Imaged-Guided Surgery (IHU Strasbourg) has two clinical Magnetic Resonance Imaging (MRI) scanners, one with a 3T (3 Teslas) magnetic field used for diagnosis, the other with a magnetic field of 1,5T (1,5 Teslas) used for the interventional (Pre / per / postoperative). The reference for the visualization of the biliary and pancreatic ducts is a relatively long sequence that needs a breathing-synchronized acquisition leading to artefacts on the images (blur effect). In order to reduce and/or standardize the acquisition time as well as to limit artefacts, accelerated sequences are developed. Such sequence is available in France recently in the form of WIP Siemens (Work In Progress: sequence in test phase at manufacturer to be marketed in the short or medium term on clinical machines). It incorporates a Compressed Sensing (CS) acquisition scheme allowing the acquisition of a 3D (3 dimensions) sequence similar to the usual sequence by drastically reducing the acquisition time, the sequence CS-SPACE. This sequence exists in two forms: * An ultra-rapid sequence acquired in apnea * An accelerated sequence but remaining synchronized with the breath. The study carried out here on a large number of patients, with two different magnetic fields, applied routinely for diagnosis or anticipation of surgery, could be used by the community of radiologists, hepatogastroenterologists and also digestive surgeons Hepatobiliary.