Iohexol versus metrizamide for cervical myelography: double-blind trial.

Cervical myelography was performed by lateral C1-C2 puncture in 60 patients. Thirty patients received iohexol (an investigational aqueous contrast agent) and 30 received metrizamide in order to provide a prospective, randomized, double-blind trial comparing these contrast media. The two media produced radiographs of equal quality. Contrast-related morbidity was suffered by four patients (13%) in the iohexol group and by 11 patients (37%) in the metrizamide group. These features indicate that iohexol is superior to metrizamide as a contrast agent for cervical myelography.