Animal Experimental Myelography in the Pig: A Comparison Between Iohexol and Iotrolan

RATIONALE AND OBJECTIVES.The authors compared the effects of a nonionic monomeric, iohexol (Omnipaque, 300 mg I/ml), and a nonionic dimeric, iotrolan (Isovist, 300 mg I/ml), contrast medium in the spinal subarachnoid space of the pig. METHODS.Lumbar and lateral C1-C2 punctures were performed in 10 pigs. Ten milliliters iohexol or iotrolan were injected via the lumbar needle. Blood pressure, electrocardiogram, intravesical pressure, and cerebrospinal fluid pressure were recorded during the injections and at intervals for 4 to 5 hours after the injections. Blood samples were taken at 30, 60, 120, 180, 240, and 300 minutes after the injections and analyzed for iodine concentration. RESULTS.No changes were seen during the injections, and there were no differences in the blood pressure, cerebrospinal fluid pressure, electrocardiographic recordings, or in the plasma iodine concentrations during the first 4 to 5 hours after the injections. Short-lasting, rhythmic bladder contractions were seen during some injections with both iohexol and iotrolan. CONCLUSION.Both iohexol and iotrolan were well tolerated, and there was no significant difference between them.