MR imaging of the small bowel with increasing concentrations of an oral osmotic agent

The aim of this study was to assess the quality of MR imaging and level of adverse effects with increasing concentrations of gastrografin. This is a prospective study with 24 healthy volunteers which were randomised into four groups receiving 50%, 25%, 10% and 0% gastrografin. The endpoint was bowel image quality based on distension, signal homogeneity and wall delineation evaluated by three independent radiologists, and the maximum bowel diameter at three different levels. The subjects also scored any adverse events on a 1-5 scale. The interradiologist agreement was relatively good, with kappa values varying between 0.81 and 0.41. Improved bowel distension and image quality were achieved with increasing concentrations. But significant dose-response effects were found between increasing osmolalities and the bowel diameters and also versus the score of adverse events. The most frequent adverse reactions were diarrhea, nausea and lack of palatability. There is a gradient relationship between increasing osmolality of gastrografin and improved image quality and the score of adverse effects. The optimum concentration of gastrografin is dependent of the tolerance of the adverse events.