Which phase reflects the rapid delivery of contrast media during a CT scan?

The phase that reflects the rapid delivery of contrast media during a CT scan is the bolus phase. This phase occurs immediately after the contrast agent is injected and is characterized by a sudden surge or "bolus" of contrast material into the bloodstream. This rapid influx increases the concentration of the contrast agent in the blood vessels, which enhances the visualization of vascular structures and organ tissues during imaging.

During the bolus phase, the peak enhancement occurs, allowing for the best differentiation between various tissues on the CT images. This is crucial for diagnostic purposes, as it aids in identifying abnormalities, tumors, and blood vessels more clearly.

Other phases, such as the equilibrium and non-equilibrium phases, describe different behaviors of contrast media as they distribute and wash out within the body. The dispersion phase relates to the spreading of the contrast agent in the vascular system but does not specifically refer to the rapid delivery characteristic of the bolus phase. Understanding these phases is essential for optimizing contrast-enhanced CT imaging and improving diagnostic accuracy.