Contrast enhanced brain CT comparison between iohexol and metrizoate.

The commonly used contrast medium metrizoate (Isopaque Cerebral) or the new nonionic iohexol was injected intravenously for enhancement of cranial CT in a randomized double blind study. Each group consisted of 105 patients. No serious reactions occurred. Ten patients receiving metrizoate had minor reactions of mainly allergic type, whereas only one patient receiving iohexol reacted. No differences in enhancement efficiency could be observed.