MRI Scans

MRI scanning is occasionally useful for digestive and liver diseases, however, gastroenterologists typically use ultrasound and CT scanning first and reserve MRI to help resolve diagnostic uncertainties. The most frequent applications of MRI are the evaluation of the bile ducts for stones and narrowed areas, the evaluation of complex pelvic and perianal inflammatory bowel disease, and in determining the nature of liver masses seen on CT.

IV contrast is sometimes given during an MRI scan. Although different from the IV contrast given during a CT scan, it may cause kidney damage in patients with pre-existing kidney disease.

MRI scanning utilizes a very powerful magnet to create images that are processed by a computer to generate image "slices" of the scanned area. Acquiring MRI images can take several minutes depending upon the area being scanned. This means that part of the patent's body will be enclosed within the scanner's tube, a small confined area, for the duration of the test. MRI scanners are also rather noisy machines. Claustrophobic patients may have difficulty with this. Most modern scanners are "small bore" machines with short tubes. "Open" MRI scanners are available but typically the image quality from "closed" scanners surpasses those from "small bore closed" scanners.

Since MRI magnets are extremely powerful, scans cannot be done in patients with certain metallic objects within their bodies. This includes patients who have cardiac pacemakers or who have fragments of metal such as shrapnel or bullets lodged in their body. If a capsule endoscopy was a performed prior to an MRI it is necessary to confirm that the capsule has left the patent's body before the MRI. Joint replacements and most surgical clips are usually not a problem. Please ask the MRI technologist if you have hardware in place before you enter the scanner.