Magnetic resonance cholangiopancreatography is a radiological examination method that produces diagnostic results for the field of internal medicine. It provides imaging of the ducts of the gallbladder and pancreas and can detect stone formation, inflammation, or new tissue formation. Because it is noninvasive and does not use contrast agents, the examination is very low-risk.
What is magnetic resonance cholangiopancreatography?
MRCP provides imaging of the ducts of the gallbladder and pancreas and can detect stone formation, inflammation, or new tissue formation. MRCP, or magnetic resonance cholangiopancreatography, is a specialized examination that falls under the specialty of radiology. Beyond the image material provided by a classic MRI of the upper abdominal organs, it can clearly depict the ductal system of the gallbladder and pancreas. For this reason, the term cholangiopancreatography contains the terms gallbladder (cholé), pancreas (pancreas) and vessel (angio). It is the non-contrast and non-invasive alternative to endoscopic retrograde cholangiopancreaticography (ERCP). As a special form of magnetic resonance imaging (MRI), it focuses on visualizing the bile ducts within the liver as well as outside this organ and images the main pancreatic ducts. Like normal MRI of the abdomen, magnetic resonance cholangiopancreatography is performed in an MRI scanner and is often ordered by the physician as an additional examination to clarify certain issues. MRCP may be necessary after an abnormal or unclear ultrasound examination (sonography) or may be performed simultaneously with MRI. More advanced examinations for a diagnosis of bile and pancreatic ducts are ERCP and EUS, endosonography, in which ultrasound is performed with the aid of a small transducer from inside the body.
Function, effect, and goals
In magnetic resonance cholangiopancreatography, the patient is wheeled into the tube, as in classic MRI, and spends about 20 to 40 minutes there on a couch, depending on the problem and examinations combined with MRCP. There are various reasons for using this diagnostic method to image the ductal system of the upper abdominal organs in greater detail. The main focus is on the visualization of gallstones, which may not be detected or only insufficiently detected with classical ultrasound. However, if one is certain that gallstones are present and need to be removed, most will go the route of ERCP: Unlike the noninvasive MRCP, it offers the possibility of removing the offending stones from the biliary system right during the examination. Another application of magnetic resonance cholangiopancreatography is the detection of inflammation in the area of the pancreas, which is often difficult to assess by ultrasound. A third possible application for MRCP is the detection of cysts or tumors, which can be benign or malignant. Here, too, the radiological examination method is usually superior to sonography. If the diagnosis of a bile duct tumor has already been established, ERCP is often chosen in this case as well in order to combine the diagnosis – if possible – with an immediate surgical intervention. In addition, this invasive examination method can also be used to obtain tissue samples for subsequent histological examination. If congenital anomalies, such as a malformation of the bile ducts, need to be diagnosed in children, this can be examined in the painless and non-stressful MRCP. If a gastroscopy is scheduled – for example, to clarify upper abdominal complaints – an ERCP can also be performed immediately, which makes magnetic resonance cholangiopancreatography unnecessary due to its unrestricted view of the ducts in the liver, gall bladder and pancreas. The advantages of MRCP are that it takes advantage of the high soft tissue contrast and fluid collection of biliary and pancreatic ducts. If necessary, it provides three-dimensional images that form a good basis for possible further therapy. If the pancreatic duct or an inflammatory disease of the bile ducts is to be imaged as part of this examination procedure, a special drug is often given that enables the duct system to be imaged even more clearly.A typical clinical picture that can be diagnosed in this way is PSC, primary sclerosing cholangitis.
Risks, side effects, and hazards
Magnetic resonance cholangiopancreatography is an examination method that carries few risks or side effects. Diagnostics in the MRI scanner – for example, in comparison with computer tomography – does not involve any X-rays, but generates meaningful cross-sectional images of the desired organs with the help of strong, but harmless to the organism, magnetic fields. Magnetism is also not a problem for the examination of children and pregnant patients. In most cases, magnetic resonance cholangiopancreatography does not require the use of a contrast agent, which could trigger an allergic reaction in the patient. In addition, MRCP scores points for being non-invasive, meaning that there is no need to fear complications from sources of bleeding that have developed or the introduction of germs into the body in conjunction with a resulting infection. There are few restrictions on the group of people who can be examined with MRCP. Anxious patients who cannot tolerate the confinement of the tube in the MRI scanner have the option of using a so-called open MRI with much larger dimensions. However, sedation of patients is possible only to a limited extent, since the quality of image acquisition during MRCP requires the cooperation of the patients: They must lie absolutely still in the device and also be able to hold their breath for up to 40 seconds so that the images can be taken optimally. However, tremendous progress has been made in the field of equipment technology, so that even artifacts caused by movements of the patients being examined can be compensated for to the extent that the desired image quality can still be achieved.
