MR Cholangiopancreatography: Improved Ductal Distention with Intravenous Morphine Administration

Abstract

Magnetic resonance (MR) cholangiopancreatography has proved a robust and noninvasive imaging modality for evaluating the biliary and pancreatic ducts without the use of ionizing radiation. Although MR cholangiopancreatography reliably depicts the main extrahepatic and intrahepatic bile ducts, it does not depict the segmental intrahepatic ducts unless they are dilated. The segmental ducts are difficult to visualize with MR cholangiopancreatography because of their small caliber and the limited spatial resolution and signal-to-noise ratio achievable with standard MR pulse sequences. However, visualization of the normal (ie, nondistended) biliary system is necessary for the evaluation of donor candidates for living related liver transplantation. Because of the prevalence of variant biliary anatomy, MR cholangiopancreatography is often used for preoperative evaluation of prospective liver donors. Intravenous morphine administered prior to MR cholangiopancreatography can improve image quality by causing the sphincter of Oddi to contract, which increases pressure in and distention of the biliary and pancreatic ducts. Morphine administration may also be particularly helpful for the evaluation of patients with primary sclerosing cholangitis, malignant neoplasms such as cholangiocarcinoma, or cystic and non-organ-deforming benign pancreatic neoplasms.

CT Cholangiography in Potential Liver Donors: Effect of Premedication with Intravenous Morphine on Biliary Caliber and Visualization

“…It is possible that radiographic biliary contrast medium itself causes biliary distension and that morphine has no incremental effect in this setting; however, this is speculative. Our study findings also contradict a review stating that premedication with morphine improved biliary visualization during MR cholangiography (18); however, in that review no data were included to support the statement. It is possible that the apparent improved definition of normal caliber bile ducts at MR cholangiography described in that review could have been secondary to reduced patient motion related to preprocedural morphine rather than a direct effect on the bile ducts.…”

Magnetic resonance cholangiopancreatography evaluation of intrahepatic bile duct variations with updated classification

“…Another is that this study was conducted in a nondilated biliary system and only the main branches of the biliary tract were observed; terminal branches were not evaluated. To evaluate the terminal branches, morphine, fentanyl, and secretin should be used to increase the contractions of sphincter of Oddi (1,(28)(29)(30)(31) , which are not used in our routine practice.…”

The diagnostic MRCP examination: overcoming technical challenges to ensure clinical success

“…In addition, the administration of secretin (2, 7, 41-44) has been used in the assessment of main pancreatic duct and pancreatic pathology. Intravenous morphine is also useful in improving distention of the biliary and pancreatic ducts as it reduces fluid outflow at the ampulla of Vater, which increases intraluminal pressure [29]. Further studies may be required to establish their validity as routine practice.…”