Metrizamide (amipaque) has not been used previously as a diagnostic contrast agent in the gastrointestinal tract. Metrizamide is a water-soluble isotonic contrast material having many advantages over barium and existing hypertonic water-soluble agents. There are many clinical situations in children in which metrizamide should be the contrast agent of choice for investigating the gastrointestinal tract. Four neonates are presented in whom barium or gastrografin were absolutely contraindicated. In each case metrizamide gave excellent visualisation of the gastrointestinal tract. It could be followed through the bowel giving excellent visualisation even up to 120h after ingestion. No harmful effects were noted in the four cases studied. (author)
Omnipaque (Iohexol) is the 2nd non-ionic contrast medium developed and marketed by Nycomed AS, Oslo. Experimental studies have shown that the toxicological and pharmacological properties of Omnipaque are closely related to those of Amipaque. However, when administered intrathecally, Omnipaque has less excitative and depressive effect upon the cerebral nervous system than Amipaque. Iopamidol is another 2nd generation non ionic monomeric contrast agent. It was considered of interest to compare those 2 media in the CNS. The main objective of this phase III trial in cervical myelography was to compare the safety, tolerance and image quality of Iopamidol and Iohexol by monitoring clinical examinations, adverse reactions (with attention to psychological disorders) as well as diagnostic information. (orig./MG)
The aim of this investigation has been to find a safe and suitable contrast medium (CM) for radiological evaluation of the gastrointestinal tract (GIT) in cases where leakage outside the GIT can be suspected. An experimental study was carried out to evaluate the reactions of various available CM in the bronchi and lungs, mediastinum, pleura and peritoneum of rats. The CM evaluated in the experimental study were, pure barium sulphate (without any additives), commercial barium sulphate (Micropaque, with additives), Dionosil, Hytrast, Gastrografin, Amipaque (in pleura Omnipaque) and Hexabrix. (Auth.)
Bryc, S.; Zelazny, S.; Losicki, M.; Orzedala, E.; Woznica, J. [Akademia Medyczna, Lublin (Poland)
The authors compared the agreement between clinical, radiological and surgical diagnoses in 33 cases of nucleus pulposus prolapse. A complete agreement of diagnosis was obtained in 88% of cases. The mechanism and incidence of different signs and their importance for the diagnosis of nucleus pulposus prolate are discussed. It should be stressed that the compression of nerve roots recognized on radiculography is not pathognomonic sign of prolapse and may be due to such process as development of marginal osteophyles in the degenerative disc disease, thickening of the posterior longitudinal ligament, hypertrophy of radicular processes or necks of vertebral archess. In the light of own experiences and data from the literature the authors consider radiculography with Amipaque and computer tomography as the method of choice in cases with suspected disc herniation in the lumbar region. (author). 27 refs, 5 figs.
Lee, Yong; Kang, Heung Sik; Chang, Kee Hyun; Han, Seoul Heui; Kwon, Oh Sung; Myung, Ho Gin [Seoul National University College of Medicine, Seoul (Korea, Republic of)
The study was conducted to compare the side effects in myelography of the two non-ionic water-soluble contrast medias, lopamidol (Niopam) and Metrizamide (Amipaque). A total of 111 patients were examined, 64 with lopamidol and 47 with Metrizamide. Side effects consisted of headache, nausea, vomiting, dizziness, urinary difficulty, muscular pain, seizure, neurobehavioral disturbance, neurological sign change, vital sign change and etc. The common side effects were headache, nausea, vomiting and dizziness in order of frequency. Most of the side effects were subsided within 24 hours following myelography. lopamidol myelography caused fewer and milder side effects than Metrizamide study. The side effects were more commonly observed in cervical, thoracic or total myelography than in lumbar myelography with either lopamidol or Metrizamide. There was no significant correlation between incidence of the side effects and premedication with phenobarbital or valium injection before myelography and CSF sampling during the procedure.
A series of lumbar myelographies -- 105 in 98 patients - was carried out with water-soluble Metrizamid (Amipaque R) in a concentration of 170 mg I/ml and showed side-effects in 32% and a quality of contrast similar to that of other water-soluble contrast media used before. The side effects were mild, of short duration and needed no treatment. There were no epileptic fits, tonic or clonic carried out 1 - 12 months later showed no signs of arachnoiditis. Dangers of more serious complications appeared to increase, the higher the level of injection into the spinal canal. A short survey of contrast media used in myelography and earlier experience of experimental or clinical side effects caused by Medtrizamid in myelography follows.
Nyman, Ulf; Ekberg, Olle; Aspelin, Peter
The Swedish radiologist Torsten Almén is the first clinical radiologist ever to have made a fundamental contribution to intravascular contrast medium design, the development of non-ionic contrast media. He became emotionally triggered by the patients' severe pain each time he injected the ionic "high-osmolar" contrast media when performing peripheral arteriographies in the early 1960s. One day he got a flash of genius that combined the observation of pain, a pathophysiological theory and how to eliminate it with suitable contrast media chemistry. After self-studies in chemistry he developed the concept of iodine contrast media not dissociating into ions in solution to reduce their osmolality and even reach plasma isotonicity. He offered several pharmaceutical companies his concept of mono- and polymeric non-ionic agents but without response, since it was considered against the chemical laws of that time. Contrast media constructed as salts and dissociating into ions in solution was regarded an absolute necessity to achieve high enough water solubility and concentration for diagnostic purposes. Finally a small Norwegian company, Nyegaard & Co., took up his idea 1968 and together they developed the essentially painless "low-osmolar" monomeric non-ionic metrizamide (Amipaque) released in 1974 and iohexol (Omipaque) in 1982 followed by the "iso-osmolar" dimeric non-ionic iodixanol (Visipaque) released in 1993. This has implied a profound paradigm shift with regard to reduction of both hypertonic and chemotoxic side effects, which have been a prerequisite for the today's widespread use of contrast medium-enhanced CT and advanced endovascular interventional techniques even in fragile patients. PMID:27225455
Till now, there is no consensus about appropriate contrast agents for use in clinical investigation in suspected perforation of the esophagus. Gastrografin, most widely used water soluble contrast agent, is less sensitive in detection of fistulous tract and can induce pulmonary edema, leading to death occasionally, if aspirated. Barium sulphate has been contraindicated without actual evaluation of its effect on mediastinum by experimental and clinical study. The purpose of this experimental study is to evaluate the type of tissue reaction and its severity in mediastinum and, as a result, to propose appropriate contrast agents in various clinical situations of suspected esophageal leakage. Barium sulphate, Hytrat, Gastrografin, Telebrix, Hexabrix, Amipaque, Niopam, and Ultravist were injected into mediastinum of 20 rats in each. The tissue reaction of injection sites were examined microscopically and graded according severity of inflammatory reaction with serial follow up from 1 day to 8 weeks after injection. The results are as follows, 1. Barium sulphate and Hytrast produced highly significant (p<0.01) tissue reaction compared to saline group and early inflammatory reaction was more severe in Hytrast. 2. Water soluble agents produced no significant reaction in mediastinum compared to saline control group and proved to be safe in the situation of leakage into mediastinum. 3. Injected barium caused no death during 8 week follow up in spite of large injected amount and histologically produced localized indolent granuloma after 4 weeks which is expected not to cause any delayed complications. In consideration of above results, superior physical characteristics of barium sulphate and drawbacks of Gastrografin, we concluded as follows. 1. For postoperative assessment of esophageal anastomosis, Barium sulphate is the contrast agent of choice