Bolus geometry and dynamics after intravenous contrast medium injection.

Abstract

Studies of contrast medium bolus geometry and dynamics were carried out to provide data for optimizing the use of contrast medium in digital subtraction angiography (DSA) and dynamic CT. Apparatus for fast digital recording of x-ray attenuation profiles was used; this is a new digital imaging mode (Chronogram) available on a CT scanner. Variables studied were injection site, injection speed, contrast medium volume, and subsequent saline injection; peak time, full width at half maximum, and maximum contrast enhancement were recorded. Positioning of the catheter in the vena cava reduced peak time and increased enhancement. High injection speeds led to shorter peak times. An increase in speed from 4 to 8 ml/s caused markedly higher enhancement, while further increase did not add significantly to enhancement. For a given injection speed, enhancement was increased and the peak time delayed by using larger injection volumes. Injection of saline solution after intravenous contrast medium did not change results significantly. There was a statistically significant correlation between pulse rate and peak time; the faster the pulse rate the shorter the peak time.

Impact of Intra-Arterial Injection Parameters on Arterial, Capillary, and Venous Time-Concentration Curves in a Canine Model

“…8,9 Our study assessed the impact of injection parameters on an intra-arte- rial bolus of contrast medium, looking not only at the effects on arterial opacification but also at opacification of parenchyma and venous structures. The bolus geometry measured in the arterial capillary and venous phases represents the effects of the injection parameters modulated by the subject's physiology (eg, patient function).…”

The effects of time varying intravascular signal intensity and k‐space acquisition order on three‐dimensional MR angiography image quality

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Pediatric hepatic CT: An injection protocol

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