Iohexol compared to metrizamide in cervical and thoracic myelography

Abstract

A randomized double blind study with iohexol (Omnipaque) and metrizamide (Amipaque) in cervical myelography was performed in 50 patients, 29 with iohexol and 21 with metrizamide. The myelographies were performed either with lumbar or with C1-C2 puncture in about equal groups, using 300 mg I/ml and 240 mg I/ml of the contrast media respectively. The image quality was equal with both contrast media, excellent in about 4/5 and good in 1/5 of the examinations. Subjective side effects were twice as frequent with metrizamide as with iohexol. The most frequent side effect was headache, occurring in 34% with iohexol and in 67% with metrizamide. Altogether 24% or the patients had EEG changes after iohexol as compared to 47% after metrizamide. All EEG changes were slight dysrythmia-except in three patients with spike activity after metrizamide. These were the only ones with mental reactions as well. It can be concluded that in this trial iohexol was better suited for cervical myelography than metrizamide.

Iohexol and Metrizamide in Lumbar Myelography

“…After iohexol, for example, total frequencies of from 4 per cent (8) to 68 per cent (26) are presented. Exclusion of patients carrying an increased risk of side effects seems to be the most important single factor for a low rate of adverse effects.…”

“…had access to the code. The puncture was performed with a 20 G needle, with the patient lying on his side on a tilting table with the head elevated to about 20° (26,32). After removal of about 5 ml of cerebrospinal fluid and injection of 10 ml of contrast medium, the exposures were made Table 2 Side effects experienced in the two groups of patients, interviewed after lumbar myelography Table 1 Demographic, procedural and image quality data in the two groups of patients after lumbar myelography tial subdural injection of contrast medium developed headache.…”

“…With metrizamide, for instance, 55 to 67 per cent of the patients have experienced various complaints (1,13,14,18,21,31). However, the development of contrast media is rapid (2), and of the new agents iohexol has proved promising for intrathecal use, both in animals (3,24) and in man (6,7,II,19,26). Only 26 to 39 per cent of the patients developed side effects in the first clinical trials (8,II,16,20,23,33).…”

Critical Assessment of Myelography Practices: A Call for Rational Guideline Revision

“…13,50 Nonionic, water-soluble radiographic contrast agents such as iohexol and metrizamide penetrate the CNS spaces and are eliminated from the subarachnoid space during 2-8 hours. 33 Most of the subjective reactions have occurred in the first 8 hours after cervical and thoracic myelography, 51 while in a study on lumbar myelography, half of all subjective reactions occurred in the first 9 hours. 22 Almost all electroencephalography changes after cervical and thoracic myelography occurred within 6 hours 51 and at 24 hours after lumbar myelography.…”

Focal epileptic activity following intravenous contrast material injection in patients with metastatic brain disease.

“…"0 Although the advent of non-ionic water soluble contrast agents into neuro-radiological practice has reduced the risk of complications, EEG changes such as dysrhythmia and spike activity have been reported following intrathecal injection. 11 The side effects caused by intravenous injection of contrast agents have been explained on the basis of histamine releasing reactions, the neurotoxicity of the contrast material, and its osmolality.' 12 Focal seizures due to fat soluble contrast material (iodophendylate) have been reported as a rare phenomenon.…”