Contrast Medium Administration and Parameters Affecting Bolus Geometry in Multidetector Computed Tomography Angiography: An Overview

Contrast medium (CM) administration for multidetector computed tomography angiography (CTA) requires using a power injector. Power injectors deliver viscous CM at different flow rates up to a maximum pressure of 300 lb per square inch (psi), provide features that benefit patient safety, improve arterial and parenchymal opacification, and allow flexible and complex injection protocols to be administered. The use of power injectors not only includes contrast but also saline, which is primarily responsible for reducing the overall volume of contrast administration while maintaining peak vessel opacification over a longer duration during the CTA acquisition. CTA faces multiple challenges with advanced scanner hardware. There is an increased need to inject small volumes of CM at fast injection rates over a short duration. This technical overview is to increase the understanding of parameters that influence optimal contrast enhancement and bolus geometry, and to enable the user to modify and optimize scanner and contrast protocols.