Iotrolan, a nonionic dimeric contrast medium in myelography.

As part of a clinical Phase III study of the nonionic, dimeric contrast medium iotrolan, differences in opacification, tolerance, and effects on the electroencephalogram after myelography were examined in a double-blind comparison with iohexol. Two groups of 25 patients each received either 10 ml iotrolan 240 mg I/ml or 10 ml iohexol 240 mg I/ml for lumbar myelography, and two groups of 50 patients each received either 10 ml iotrolan 300 mg I/ml or 10 ml iohexol 300 mg I/ml for lumbar, thoracic or cervical myelography. The overall assessment of the opacification in the subarachnoid space, which was moderate in only one case of each group and otherwise good, showed no differences between the preparations. The tolerance of both concentrations of iotrolan proved to be significantly better than those of iohexol: at a significance level in the chi-square test of p less than 0.001 in a simple size of 25 patients per preparation with 240 mg I/ml and at a significance level of p +/- 0.05 in a sample size of 50 patients per preparation with 300 mg I/ml.