[Oral contrast media in CT: improvement by addition of guar?]

To evaluate the additional effect of guar with iotrolan as an oral contrast medium.

In a clinical double-blind randomised study a viscous iotrolan (11.2 mg iodine/ml)/guar (4 g/l)-suspension was compared with aqueous solutions of pure iotrolan (11.2 mg iodine/ml) and meglumine ioxithalamate (12 mg iodine/ml). The contrast media were evaluated according to filling, distribution, transit time, artifacts, radiodensity, patient acceptance and side effects.

The addition of guar delayed the transit time of the contrast media. Consequently a more homogeneous filling of the bowel with fewer artifacts was observed in comparison to the aqueous contrast media. The results of the pure iotrolan solution were comparable to meglumine ioxithalamate, except for a higher radiodensity in the distal small intestine. The colon showed a better filling with non-viscous contrast media in the given time frame. Pure iotrolan had the best patient acceptance. Two patients considered the iotrolan/guar-solution impossible to drink, the other 18 patients found taste and consistency just about acceptable.

In spite of the discussed advantages, due to a less subjective acceptance the guar/iotrolan solution is not suitable in routine-diagnosis, unless taste and consistency are greatly improved. Individual use is recommended in selected cases and long-term examinations.