From the Guidelines
For patients undergoing MRCP preparation, I strongly recommend using a heavily T2-weighted fluid-sensitive 3-D sequence, acquired over 3 to 5 minutes in the coronal plane using respiratory triggering or diaphragmatic gating, without the need for IV contrast administration for the detection of ductal calculi. This approach is based on the most recent and highest quality study available, which was published in the Journal of the American College of Radiology in 2019 1.
Key Points for MRCP Preparation
- MRI is an advanced noninvasive imaging technique that offers improved contrast resolution over CT and US, and can accurately demonstrate both the site and cause of biliary obstruction.
- MRCP can be performed without IV contrast administration for the detection of ductal calculi, with a reported sensitivity ranging from 77% to 88% and specificity between 50% to 72% 1.
- The use of IV contrast administration with MRCP improves the sensitivity for the detection of peribiliary enhancement and improves the confidence in the diagnosis and staging of unsuspected pancreaticobiliary tumors, but is not necessary for the detection of CBD stones.
- MRCP has diminishing sensitivity with decreasing stone sizes of <4 mm, and the sensitivity may be affected by stones in the gallbladder that pass into the CBD between the MRCP and the ERCP.
Advantages of MRCP
- MRCP is less morbid than ERCP imaging and offers superior accuracy compared to ERCP or EUS in patients with previous gastroenteric anastomoses.
- MRCP is the preferred imaging modality in patients with suspected sclerosing cholangitis or biliary stricture, avoiding the possibility of suppurative cholangitis that may be induced by endoscopic catheter manipulation of an obstructed biliary system.
- MRCP findings may guide directed approaches, such as ERCP, with brushing, percutaneous transhepatic biliary stenting, or reconstructive surgery.
From the Research
MrCP Preparation
There are no research papers to assist in answering this question as the provided studies do not mention MrCP preparation.
- The studies provided focus on topics such as the perioperative management of patients with implanted pacemakers, defibrillators, and neurostimulating devices 2, MRI conditional pacemaker and lead technology 3, alprazolam use, misuse, and withdrawal 4, 5, and the association of alprazolam with major cardiovascular events in patients with hypertension 6.
- None of these studies provide information on MrCP preparation.