Automated IV contrast injection applying high flow rates (i.e., up to 8 mL/s) is performed without increased risk of extravasation. The overall extravasation rate was 1.2% and showed no correlation with iodine concentration, flow rates, or contrast material reactions. Performing high flow rates with low-diameter IV catheters (e.g., 22-gauge catheters) and a location of IV catheter in the hand is associated with a higher extravasation rate.

Over the past 120 years, continuous developments in medical imaging has improved diagnosis and treatment for many diseases and has thereby improved treatment outcome and quality of life of many patients. The number of computed tomography (CT) examinations is today increasing by 4% per year worldwide, for a total of approximately 300 million CT scans per year. About 40% of CT scans are contrast enhanced. Intravenous iodinated contrast media are commonly used for contrast enhancement in CT scans to evaluate diseases and determine treatment response. The current gold standards for intravenous x-ray contrast media in CT or interventional angiography are iodinated low- and iso-osmolar compounds such as iopromide, iohexol, or iodixanol. Both classes have similar and favorable efficacy and safety profiles. Although iodine is biologically inert, iodinated contrast media can cause adverse reactions. In the future, one possibility would be to develop iodine-free contrast media that are better suited to higher x-ray tube voltage ranges, allowing greater flexibility for scanning protocols and thus leading to techniques that can provide equivalent diagnostic value at lower doses of radiation. Iodine-free contrast media would in addition provide an alternative to the market standard that could offer benefits for patients with known reactions to low-osmolality contrast media or thyroid disorders. The development of a new contrast medium, however, needs to be put in context with all upcoming technological advances in x-ray and CT. New detector technologies and artificial intelligence algorithms will in the future also improve the CT image reconstruction enabling the reduction of contrast media and radiation doses.

No abstract

In computed tomography (CT) several contrast media with different iodine concentrations are available. The aim of this study is to prospectively compare contrast media with iodine concentrations of 300, 370 and 400 mg iodine/ml for chest- CT. 300 consecutive patients were prospectively enrolled, under a waiver of the local ethics committee. The first (second, third) 100 patients, received contrast medium with 300 (370, 400) mg iodine/ml. Injection protocols were adapted for an identical iodine delivery rate (1.3 mg/s) and total iodine load (33 g) for all three groups. Standardized MDCT of the chest (16 x 0.75 mm, 120 kVp, 100 mAseff.) was performed. Intravascular attenuation values were measured in the pulmonary trunk and the ascending aorta; subjective image quality was rated on a 3-point-scale. Discomfort during and after injection was evaluated. There were no statistically significant differences in contrast enhancement comparing the three contrast media at the pulmonary trunk (p = 0.3198) and at the ascending aorta (p = 0.0840). Image quality (p = 0.0176) and discomfort during injection (p = 0.7034) were comparable for all groups. General discomfort after injection of contrast media with 300 mg iodine/ml was statistically significant higher compared to 370 mg iodine/ml (p = 0.00019). Given identical iodine delivery rates of 1.3 g/s and iodine loads of 33 g, contrast media with concentrations of 300, 370 and 400 mg iodine/ml do not result in different intravascular enhancement in chest-CT.

Given equivalent iodine load and delivery rate, the use of 300 mg I/mL contrast medium results in better contrast enhancement than use of 370 mg I/mL contrast medium in CT of the chest. For the portal venous phase of CT of the abdomen, there was no significant difference in contrast enhancement for the two concentrations of iodine.

CIN is a rare complication in acute stroke patients examined by multimodal contrast-based CT due to the low prevalence of risk factors associated with CIN. In conjunction with appropriate fluid substitution, low osmolar nonionic contrast agents seem to be safe in clinical routine.

A prolonged retention of contrast media in the kidney was observed after administration of dimeric CM (Iodixanol 320). One possible explanation for this effect could be the high viscosity of the dimeric CM (Iodixanol 320) and the lack of dilution by osmotic diuresis. This prolonged exposure is possibly associated with higher renal toxicity as indicated by the elevated expression of biomarkers for hypoxia and renal injury.

PCT allows the discrimination of patients without a relevant risk for MBI from those having a 50 % risk of MBI development. Due to the high sensitivity and specificity, PCT is a reliable tool in detecting MBI. Because of PCT's better availability, it is the method of choice at present for an early risk stratification of acute stroke patients.