Table 1.

Semi-quantitative Parameters

	Description
Peak enhancement	The difference between the maximum signal intensity and baseline signal intensity. A ratio of the maximum signal and baseline signal intensities, or the relative signal intensity change between the maximum and baseline signal intensities can be used.
Time to peak	The time from baseline to the peak of the Signal Intensity Time Curve (STC)
Wash-in slope	The slope of the uptake of the STC from the baseline to the peak of the STC
Wash-out slope	The slope of the STC from the maximum signal intensity to the end of the STC
Area under the curve	The area under the STC. The area calculated from the initial uptake portion of the STC for a time point is most commonly used, such as iAUC60 refers to the area under the initial uptake curve for the first 60 seconds.