The sequential steps for converting blood measurements to an input curve are explained in a dedicated section. The current plasma fraction model serves for converting a whole-blood activity curve into a plasma-activity curve.
It is assumed that a curve representing the measured ratio of plasma/whole-blood activity has been loaded with Load Plasma/WB Ratio.
The Lin. Interpolation model interpolates linearly between the measured fraction values. Outside the measured values the following interpolation rules apply:
▪The fraction at time t=0 is assumed to equal 1.
▪The fraction is assumed to remain constant after the last measured fraction.
For incomplete fraction data it is therefore recommended to replace the tail of the measurements by a fitted tri-exponential model.
Parameter Fitting
There is nothing to fit with the Lin. Interpolation model.