Optimising the use of iodinated contrast agents in CT scans: Vascular, visceral, multiphasic and split-bolus examinations

Iodinated contrast is administered when carrying out computed tomography (CT) scans to define anatomical structures and detect pathologies. The contrast is administered according to different protocols which vary significantly and include vascular, visceral, multiphasic and split-bolus injection studies. Each protocol has its own indications and particularities to optimise the use of the contrast medium in each situation. There are numerous factors that influence the degree of contrast enhancement obtained, including the patient’s weight, cardiac output, study delay, the technical characteristics used for acquisition—mainly kilovoltage—, and variables related to the administration and dosage of the contrast medium, such as iodine delivery rate and load. This article will discuss how each of these variables affects the level of enhancement achieved and the parameters that can be modified in order to optimise the results of the different types of scans performed with iodinated contrast.