Kinetics of intravenous radiographic contrast medium injections as used on CT: simulation with time delay differential equations in a basic human cardiovascular multicompartment model.

Objectives: To develop a multicompartment model of only essential human body components that predicts the contrast medium concentration vs time curve in a chosen compartment after an intravenous injection. Also to show that the model can be used to time adequately contrast-enhanced CT series.

Methods: A system of linked time delay instead of ordinary differential equations described the model and was solved with a Matlab program (Matlab v.

Kilovoltage dependence of the attenuation of a potassium iodide/water solution on CT: presentation of a computer model implementing polychromatic character of the X-ray photon beam.

Purpose: To describe a program that simulates a computed tomographic scan with the polychromatic aspect of the output of the x-ray tube implemented. This program can be used in the study of the attenuation of different solutions/solutes. These results can subsequently guide the radiologist to obtain a satisfying contrast enhancement at lower tube voltages and eventually lower contrast volumes.

Stabilization of the hydrophilic sphere of non-ionic monomers: are all protected in a similar way?

The present study attempts to investigate whether incorporation of a methyl group as second substituent in the tertiary amido group of the two benzamide side chains of iobitridol (Xenetix) increases the stability of the hydrophilic sphere around this molecule as claimed by its manufacturer, and whether this hydrophilic sphere is unique to this particular molecule or to what extent other monomer non-ionic contrast media show this feature. Five non-ionic monomer contrast medium molecules, ioversol, iohexol, iobitridol, ioxilan and iopromide, were studied. Barriers to the rotation of acetanilide and benzamide side chains, and to the rotation of the amide bond in the benzamide chains, were calculated at a semi-empirical quantum mechanical level of theory with the Mopac/Ampac computer program.

Renal failure and iodinated contrast media. A review.

Contrast medium-induced renal failure is reported to be a very frequent adverse effect (up to 70% incidence) that often goes undetected. Consequences are sometimes very dramatic and can even lead to irreversible renal damage and renal dialysis. Basically, four groups of mechanisms will be considered: decrease of renal perfusion and increased vascular resistance, glomerular injury, tubular injury, and obstructive nephropathy.