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Magnetic resonance (MR) imaging is a diagnostic imaging technique that uses the magnetic properties of elements to produce clearly differentiated images of tissues and organs. One of its uses is imaging the head and spine for detecting abnormalities of the central nervous system (CNS). As with other imaging techniques, contrast agents often help enhance MR images and allow for more accurate detection of abnormalities. This study examined the effectiveness and safety of the nonionic compound gadodiamide in MR imaging. MR imaging of the brain and spine along with injection of gadodiamide was performed on 439 patients who had either suspected or known CNS abnormalities. Adverse side effects from the agent were reported by 46 (10.5 percent) of the patients. Headaches, nausea, and dizziness were the most commonly reported side effects; no serious side effects were reported. CNS abnormalities were detected by MR imaging, with or without the contrast agent, in 353 (80.4 percent) of the patients. The gadodiamide enhanced imaging of these abnormalities in 266 of the 353 patients. In 28 patients, no abnormality was seen when MR imaging without gadodiamide was performed. Gadodiamide enhancement changed the diagnosis for 70 patients and facilitated diagnosis for 190 patients. These results indicate that gadodiamide is both safe and effective for use as a MR imaging contrast agent when evaluating possible CNS abnormalities. (Consumer Summary produced by Reliance Medical Information, Inc.)

The diagnostic use of magnetic resonance (MR) imaging has increased beyond original expectations. It is used to characterize abnormalities in many areas of the body. Until recently, its use in abnormalities in the pelvic region has been more limited. Studies have shown MR to be useful in diagnosing tumors in the liver as well as in other organs of the pelvis, but for a number of reasons it is still not widely used. The lack of an effective and safe contrasting agent for imaging the bowels prevents MR from becoming the major diagnostic tool for most pelvic organs besides the liver. Motion caused by the heart and lungs interferes with MR imaging in this area. Recent research shows that MR imaging is useful in finding and characterizing localized tumors in pelvic organs, as motion is less of a problem with this use. Other research has shown the superiority of using MR over computed tomography (CT) in imaging localized tumors in other areas of the body. MR works especially well on organs surrounded by fat such as the uterus. The use of MR for finding rectal tumors has yielded mixed results, although new research has indicated that good results may be obtained if the techniques are used very carefully. MR does have its limitations. It is not highly successful in differentiating between normal and enlarged lymph nodes. It is also less effective in previously treated patients, where treatment has affected tissue. The future of MR is bright, nevertheless. Proper technique is vital to its use. Improved technology and development of new contrast agents will expand its scope and power as a diagnostic tool. (Consumer Summary produced by Reliance Medical Information, Inc.)