Iohexol 240 mgr I/ml and metrizamide 240 mgr I/ml in lumbar myelography. Report from a randomized double blind study.

A parallel, double blind, randomized study, comparing iohexol 240 mg I/ml and metrizamide 240 mg I/ml in lumbar myelography was carried out. Fifty patients were admitted to the study, and 1 patient was excluded after entry. Of the 49 patients included, 28 were males and 21 females, aged between 18 and 72 years. A dose of 10.5 ml of contrast medium was administered. A detailed neurological examination, and measurement of blood pressure and heart rate were performed before and 24 h after myelography. EEG was recorded in 37 patients. All patients were observed for adverse reactions for 48 h. Adverse reactions were reported in 14 of 26 patients examined with iohexol, and in 13 of 23 patients examined with metrizamide. EEG changes were observed in 7 patients examined with metrizamide, no changes were observed in patients examined with iohexol. The image quality was judged good or excellent in all cases, with the upper level of contrast medium brought to the level of L1 in the majority of cases.