[Oral magnetic particles as an MR contrast medium for the gastrointestinal tract]

The authors summarise their experience of four clinical studies with a negative oral contrast agent for magnetic resonance imaging of the abdomen and pelvis. 140 patients were enrolled in the studies. These were partly comparative studies pre- and post-contrast, partly at 0.5 and 1.5 T, partly pre-injection and post-injection of glucagon. All patients received 800 ml of a suspension of oral magnetic particles "OMP". The distribution of this contrast agent was homogeneous throughout the entire GI tract. A complete or partial signal void was observed in all patients in T1, T2-, and intermediately weighted images. Generally, diagnostic information was higher after contrast. Artifacts caused by peristalsis and movement of the diaphragm were fewer after contrast. After contrast metallic artifacts were observed in a minority of patients. Adverse events after contrast were minimal; they included nausea and vomiting.