Is there an increased risk of early side effects of metrizamide in post-myelogram computed tomography?

The safety of post-myelogram computed tomography (PMCT) as an additional diagnostic procedure to metrizamide myelography was evaluated. One hundred and four consecutive patients with suspected cervical cord lesions were studied prospectively; 50 had both myelography and PMCT, and the 54 acting as controls had only myelography. PMCT did not increase the incidence, severity or duration of common side effects and the majority of patients accepted this additional procedure. It is concluded that as long as care is taken to avoid the occurrence of excessive contrast in the intracranial subarachnoid space, PMCT is a safe procedure.