This article is to present the experience in 1,000 cases given intrathecal Iohexol injection during 1985-1988, including conventional myelography in 343 cases, conventional and CT myelography in 572, only CT myelography in 60 and CT cisternography in 25. No convulsions were observed. The frequency of headache was 11.6% and the total uncomfortable subjective reaction was 19.6% after intrathecal injection, but no serious complications were found. Because of very low frequency of side effects after this injection, most of the examinations can be made in the outpatient departments. In our clinical experience, Iohexol appears to be a myelographic contrast medium with diagnostic capabilities and less morbidity compared to Metrizamide. Thus Iohexol seems to be well suited for intrathecal injection and will replace metrizamide in this respect.