Omnipaque and urografin in arthrography of the knee

The first experience with Omnipaque in arthrography of the knee in patients is reported. Forty arthrographies were performed using either Omnipaque 350 mg I/ml or Urografin 370 mg I/ml at random. The low-osmolar non-ionic Omnipaque showed a tendency for pain of shorter duration and lower incidence of hydrops. A significantly lower incidence of complaints of tension and swelling and assessed reactive synovitis was demonstrated. Both contrast media produced excellent synovial coating on standard series, but Omnipaque showed a slower decrease in attenuation.     

Iohexol and ioxithalamate for intravenous urography. A comparative parallel study

Omnipaque (iohexol) 350 mg I/ml has been compared with Telebrix (ioxithalamate) 380 mg I/ml in 48 patients undergoing intravenous urography. The contrast medium dose corresponded to 400 mg I/kg body weight. No cardiovascular reactions (BP and pulse rate) were observed. Subjective reactions occurred somewhat more frequently after Telebrix than after Omnipaque. Sensation of warmth was significantly less with Omnipaque (p less than or equal to 0.05). The overall radiological quality was equally good for the two contrast media.     

Iohexol in coronary angiography. A double blind investigation

Iohexol 350 mg I/ml (Omnipaque) was compared with the routine contrast medium meglumine, Na-Ca-metrizoate 370 mg I/ml (Isopaque Coronar) in coronary angiography in 30 patients. A randomized, double blind, crossover design was employed. Angiographic image quality, ECG, heart rate, aortic blood pressure and adverse reactions were recorded. Excellent image quality was obtained with both media. Except for one single event of hypotension, only few and minor changes in the parameters measured were recorded. No distinct difference between the two media was found. Iohexol seems to be suitable for selective coronary angiography.     

Iohexol and ioxaglate in peripheral angiography

A double-blind, cross-over trial of the non-ionic, low-osmolar contrast medium iohexol (Omnipaque) and the ionic, low-osmolar medium ioxaglate (Hexabrix) at concentrations of 300 mg I/ml was carried out in 107 consecutive patients with arterial insufficiency of the lower limbs. The purpose of the study was to observe possible 'carry-over' effects from any of the contrast media, and to evaluate patient discomfort such as pain, adverse reactions, or effect on peripheral blood pressure. No carry-over effect was seen. Ioxaglate caused less injection pain and heat sensations than iohexol, and showed less effect on the systemic blood pressure.     

Clinical testing of omnipaque and amipaque in external carotid and vertebral angiography: randomized double-blind crossover study

Omnipaque, 300 mg l/ml, was compared with Amipaque, 300 mg l/ml, for cerebral angiography. Twelve patients were included in a randomized, double-blind, crossover study. Twenty comparisons were made in the external carotid and 21 in the vertebral artery, Both contrast media caused no or minor changes in blood pressure and heart rate. Good to excellent radiographic visualization of the cerebral arteries was obtained with both agents. The frequency of subjective reactions was almost equal, but the intensity of the reactions was less with Amipaque. No severe reactions were observed. Omnipaque is a more practical nonionic contrast medium than Amipaque because it is delivered in ready-to-use solutions.     

Iohexol compared to metrizamide in cervical and thoracic myelography

Summary 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.     

Non-ionic contrast media: a comparison of iodine delivery rates during manual injection angiography

Iodine delivery rates (IDR) of five commonly used non-ionic contrast media were determined at room temperature (24 degrees C) and body temperature (37 degrees C). Contrast media of strength 300 mgI/ml were also evaluated at 50% dilution (150 mgI/ml) with N-saline. Iodine delivery differed significantly (p less than 0.005) between samples at room temperature: Omnipaque 350 (1163 mg/s) less than Niopam 370 (1311 mg/s) less than Omnipaque 300 (1422 mg/s) less than Niopam 300 (1635 mg/s) and Ultravist 300 (1636 mg/s). Niopam 300 and Ultravist 300 delivered 41% more iodine per second than Omnipaque 350 at room temperature. Similar differences were identified at body temperature, while delivery of individual media was on average 23.5% greater than at room temperature. No significant difference between iodine delivery rates of diluted media at room temperature or body temperature was identified. The results demonstrate that iodine delivery and hence vascular opacification are better achieved during hand-injection arteriography by using relatively low viscosity media such as Niopam 300 or Ultravist 300. In digital subtraction arteriography all 300 strength contrast media diluted to 150 strength are equally effective.     

Comparison of iohexol 300 mg I/ml and Hexabrix 320 mg I/ml in central angiography

Summary Iohexol 300 mg I/ml and Hexabrix 320 mg I/ml have been compared in a randomized, double blind, parallel study, to evaluate hemodynamic parameters, diagnostic information and adverse reactions. A total of 55 patients entered the study, one of them was later excluded, bacause both contrast media were given by mistake. In the included material, 21 patients were given iohexol 300 mg I/ml in 55 selective injections and 23 patients Hexabrix 320 mg I/ml in 65 selective injections. The median total dose was 52 (12–88) ml in the iohexol group and 51 (13–118) ml in the Hexabrix group. No changes in heart rate were seen. Angiograms of good or excellent quality were obtained, and no difference between the two media was shown. No serious adverse reaction accured, and no statistical significant difference was found between the two media with respect to subjective patient reactions. The results indicate that the non-ionic, low-osmotic contrast medium iohexol is well tolerated in cerebral angiography with respect to the parameters tested. No statistical significant difference was found in any of these parameters between iohexol and Hexabrix.     

Myelography with a dimeric (iodixanol) and a monomeric (iohexol) contrast medium: a clinical multicentre comparative study

The purpose of this study was to evaluate and compare the radiographic efficacy and safety of iodixanol (Visipaque; 270 and 320 mg I/ml) and iohexol (Omnipaque; 300 mg I/ml) in myelography. The study was randomized, double-blind and comparative including 398 patients from five European university clinics. The radiographic visualisation was evaluated as poor, good or excellent. Adverse events were recorded by interviewing the patients after the myelography, and each patient was given a questionnaire to be returned after 1 week. In cervical myelography with cervical puncture more films with excellent quality was obtained after iodixanol 320 mgI/ml compared with iohexol 300 mgI/ml (p = 0.009). Also in lumbar myelography iodixanol 320 mgI/ml compared favourably with iohexol 300 mgI/ml (p = 0.006). The most frequent adverse event was headache, which occurred in 5–35 % of patients during the first 24 h and in 19–61 % within the first 7 days, depending on the centre. There was no difference in frequency and severity of the adverse effects between the contrast media. Received 13 March 1997; Revision received 29 December 1997; Accepted 5 January 1997     

High dose urography in patients with renal failure. A double blind investigation of iohexol and metrizoate

The new non-ionic contrast medium iohexol 350 mg I/ml was compared with the ionic contrast medium metrizoate 350 mg I/ml in a double blind, two-group urographic study performed on 20 patients with stable, impaired renal function. A dose of contrast medium of 500 mg I/kg body weight was given to each patient. Iohexol resulted in significantly fewer subjective adverse reactions than metrizoate. A similar image quality was obtained with the two contrast media. No clinically significant difference existed between the two contrast media with respect to influence on blood pressure, pulse or clinical chemical parameters. A tendency to deterioration of renal function after urography was found in both groups, but no difference of statistical significance existed between the two contrast media with respect to possible nephrotoxicity. Inadequate hydration may have been partly responsible for the nephrotoxic effect of the urographic procedure.     

High- and low-osmolar contrast agents in urography: a comparison of the appearances with respect to pyelotubular opacification and renal length

The incidence of pyelotubular opacification and the change in renal length during intravenous urography with iohexol (Omnipaque) was compared with sodium/meglumine diatrizoate (Urografin). Pyelotubular opacification was seen in 14 out of 29 urograms performed with iohexol compared with one out of 28 urograms performed with sodium/meglumine diatrizoate. This increased incidence is statistically significant and has not been previously documented. The increase in renal length following intravenous contrast medium was similar for both iohexol and sodium/meglumine diatrizoate. The significance of these findings with respect to the interpretation of urograms performed with iohexol is discussed.     

Low dose urography. A clinical comparison of three low osmolar (ratio 3) contrast media

Three modern low osmolar contrast media (Iopamiro, Omnipaque and Hexabrix) were injected intravenously in 150 patients. They were all effective for urography in a concentration iso-osmolar to blood and with a dose of 90 mg I/kg body weight in patients with normal renal function. In patients with decreased renal function, this low dose is not sufficient and should be doubled. No significant diagnostic differences between the three media were found. The subjective and objective adverse effects were minimal and transient.     

Low- versus high-osmolality contrast media

PURPOSE: To evaluate the effects of contrast media pharmokinetic differences on aortic enhancement at abdominal CT angiography and to determine whether these effects are of clinical relevance. MATERIAL AND METHODS: Two hundred and twelve patients referred for abdominal CT angiography were included in the study. All abdominal CT angiograms were performed with the same parameters (collimation 3 mm, pitch ratio 1.7, scan delay 30 s) after i.v. injection of 120 ml of contrast medium at 3 ml/s. After randomization, patients received either iobitridol 300 (low-osmolar, 300 mg I/ml), iobitridol 350 (low-osmolar, 350 mg I/ml) or ioxithalamate 350 (high-osmolar, 350 mg I/ml). The time attenuation curves obtained with the three contrast media were compared. RESULTS: The time attenuation curve obtained with ioxithalamate 350 was not parallel to those obtained with iobitridol 300 and iobitridol 350. Mean peak enhancements obtained with iobitridol 350 and ioxithalamate 350 were not significantly different but iobitridol 350 provided higher mean peak enhancement than iobitridol 300. Mean delays of the peak enhancements were the same with the three contrast media. After peak enhancement, the decrease of aortic opacification under a selected threshold of 200 HU was significantly slower with iobitridol 350 than with iobitridol 300 and ioxithalamate 350, whereas iobitridol 300 and ioxithalamate 350 showed no significant differences. CONCLUSION: For a given iodine concentration, low-osmolality contrast media provide longer aortic opacification and may be recommended for CT angiography when long acquisition times are needed.     

Comparison of iodixanol 270 with iohexol 300 in infrapopliteal arteriography. Digital densitometric analysis of angiographic opacification.

PURPOSE: To compare iodixanol 270 mg I/ml with iohexol 300 mg I/ml in infrapopliteal arteriography by measuring digital densitometric vessel opacification and by visually assessing angiographic enhancement. MATERIAL AND METHODS: In a double-blind, dual-balanced, 4-sequence cross-over design, 50 claudicant patients received two contrast media injections (10 min interval) in the superficial femoral artery. Digital angiography was performed at 8 frames/s and time-density curves with a circular region of interest over a distal calf artery were generated. A mixed, linear model was used to identify effects influencing the density measurements. Subjective evaluation of the image quality was made independently by two observers. RESULTS: No statistically significant difference between the contrast media was revealed in the analysis of the densitometric measurements (p=0.14) nor in the subjective visual evaluation (p=0.74). However, the mean density at the time of maximum opacification was higher after the first injection than that after the second injection (p=0.02). There was a tendency towards lower intensity of warmth during injection of iodixanol 270 than during injection of iohexol 300. CONCLUSION: In patients with severe occlusive atherosclerotic disease, iodixanol yielded the same image quality as iohexol in infrapopliteal arteriography, in spite of the 30 mg I/ml lower iodine concentration.     

Clinical testing of Iohexol,Conray meglumine and Amipaque in cerebral angiography

Summary Iohexol 300 mg I/ml, Conray meglumine 282 mg I/ml and Amipaque 300 mg I/ml have been compared in a randomized double-blind cross over study in which one injection of Iohexol 300 mg I/ml and Conray meglumine 282 mg I/ml was made in the same artery (common and internal carotid artery) of the same patient, and one injection of Iohexol 300 mg I/ml and Amipaque 300 mg I/ml was made in another artery (external carotid artery and vertebral artery). All together 63 cerebral artery branches were examined in 27 patients, who served as their own controls. The effect of the contrast injections on the intraarterial blood pressure, pulse rate, ECG, circulatory rate and the patients' reactions were recorded under standardized conditions. The quality of the film was also evaluated. No significant difference was found in the cardiovascular effects after the injection of Iohexol or Conray meglumine into the common carotid or internal carotid. There was significantly less pain and sensation of warmth after the injection of Iohexol than after Conray meglumine 282. In the vertebral and the external carotid arteries, where a comparison between Iohexol and Amipaque was carried out, it was found that no significant difference in the cardiovascular effects occurred. There was less sensation of warmth after the injection of Amipaque into the vertebral artery than was caused by Iohexol. The degree of discomfort in form of pain reaction was the same for the two media, when these reactions occured. No serious side effects were observed.Read at the Annual Meeting of the Scandinavian Society of Neuroradiology, August 1981     

Evaluation of lopamidol and diatrizoate in excretory urography: a double-blind clinical study

Image opacification, patients' tolerance, and clinical and laboratory findings were evaluated in patients having excretory urography at three centers. In a double-blind, parallel study, iopamidol was compared with diatrizoate (50-ml dose), and in an open-label trial, the administration of a 100-ml dose of iopamidol was evaluated. In the double-blind study, a total of 84 patients received 50 ml of either iopamidol or diatrizoate. In the open-label study, another 42 patients received a 100-ml dose of iopamidol. Image opacification scores after the administration of the 50-ml doses showed better opacification with iopamidol than with diatrizoate in the renal calices (p less than .05) and in the composite kidney (p less than .05). Opacification scores were higher for 100-ml doses of iopamidol than for 50-ml doses in all anatomic regions as well as in the composite kidney (p = .0001). Patients' tolerance to iopamidol was significantly better than their tolerance to diatrizoate (p less than .025). Investigators observed adverse drug reactions in a total of 10 patients. In the double-blind study, one of 43 patients had transient bradycardia after the administration of iopamidol. In the same study, four of 41 patients who received diatrizoate had five minor adverse drug reactions. With 100-ml doses of iopamidol, five of 42 patients had adverse reactions. No adverse side effects required therapy in either study. There were no significant changes in vital signs or laboratory values after drug administration. The results of this study show that iopamidol is a suitable agent for excretory urography at doses of 50 and 100 ml. Patients report fewer unpleasant side effects with iopamidol than with diatrizoate. Overall image quality was better with iopamidol than with diatrizoate. Overall evaluation of drug performance was better with iopamidol than with diatrizoate.     

Cervical myelography with iohexol

An open, non comparative study of cervical myelography in 68 adult patients using iohexol (Omnipaque) containing 300 mg I/ml is reported. Satisfactory visualisation was achieved in all cases. Minor adverse effects occurred in 13 patients (19%); they were headache (8), neck or back pain (3), vomiting (3), nausea (1), dizziness (1) and nystagmus (1) and were of minor degree in most and moderate in a few, lasting more than 24 hours in only one patient. EEG performed in 39 patients before and 24 h after the myelogram showed no seizure activity or significant change. Iohexol is a very satisfactory drug for all types of myelography.     

Arthrography of the knee joint with amipaque.

In a double-blind investigation, 30 knee arthrographies were performed by injection of either Amipaque 290 mg I/ml or Urografin 60% (292 mg I/ml). Both contrast media are well tolerated, and give excellent initial contrast quality, which deteriorates rapidly. This occurs more slowly with Amipaque, which has lower osmolality and causes less joint effusion.     

Effects in vivo of iohexol and diatrizoate on human plasma acetyl- and butyryl-cholinesterase activity

PURPOSE: The aim of this study was to evaluate the effects of two iodinate contrast agents (CA), iohexol and diatrizoate, on human plasma acetyl-(AC) and butyrylcholinesterase(BC) activity. MATERIAL AND METHODS: Forty-eight patients (24 males and 24 females) scheduled for intravenous pyelography were randomly divided into four groups of 6 males and 6 females each, receiving as CA, respectively: iohexol (Omnipaque, Schering) 0.6 ml/kg body weight (G1); iohexol 1.2 mg/kg (G2); sodium and meglumine diatrizoate 58% (Urografin, Schering) 0.6 ml/kg (G3); sodium and meglumine diatrizoate 58% 1.2 ml/kg (G4). Blood samples were taken before and 5, 10, and 20 min after the injection. Enzymatic activity of AC and BC were measured by spectrophotometry. Plasma concentration of K, Na, Ca, and Mg was measured in all blood samples; blood pressure and plasma pH were measured after each sample collection. Statistical analysis was performed by Student's test. RESULTS: In G1 a reversible decrease of AC (12.9%) and BC (8.2%) plasma activity was observed at 10 min. In G2 a progressive decrease of AC (13.9%) and BC (18.4%) plasma activity was observed with a maximum at 20 min. In G3 a modest reversible decrease of BC plasma activity (5.4%) was observed. In G4 a modest progressive decrease of AC (7.3%) and BC (6.5%) plasma activities was observed. In all cases, AC and BC plasma activities remained within the normal range of values. Plasma concentration of K, Na, Ca, and Mg, as well as pH and systolic and diastolic pressure, did not show any change. No adverse effects was observed in our patients. CONCLUSIONS: Iohexol and diatrizoate induce in vivo a significant decrease of AC and BC plasma activities. The decrease is more pronounced for iohexol, a non ionic CA, which has a lower pharmacotoxicity than diatrizoate and adverse effects rate. No inference can be drawn about the relationship between plasma cholinesterase activity and adverse effects.     

Comparative double-blind investigation of meglumine metrizoate, metrizamide, and iohexol in carotid angiography

The new nonionic contrast medium iohexol (Omnipaque) was compared with its predecessor metrizamide (Amipaque) and with the conventional ionic medium meglumine metrizoate (Isopaque Cerebral) in carotid angiography using a double-blind crossover technique. The results indicated that iohexol and metrizamide caused less discomfort than the ionic medium. The circulatory effects of the three media were generally mild, and the diagnostic effectiveness was comparable when the iodine concentration was kept in the range of 280-300 mg I/ml.