The quantification of dynamic PET studies to measure Ki requires the measurement of the skeletal time-activity curves (TAC) from the region of interest (ROI) and the arterial input function (AIF), which can be measured in various different ways. However, the most common is to correct the image-based blood time-activity curves using several venous blood samples taken at discrete time points while the patient is scanned. The calculation of rate constants or K requires three steps:
* Measurement of the arterial input function (AIF), which acts as the first input to the mathematical model of tracer distribution.
* Measurement of the time-activity curve (TAC) within the skeletal region of interest, which acts as the second input to the mathematical model of tracer distribution.
* Kinetic modelling of AIF and TAC using mathematical modelling to obtain net plasma clearance (K) to the bone mineral.