The parameters in this dialog menu provide inital estimates and scalings for the bolus fitting based perfusion analysis. The parameter defines the region of the data (stating from zero) used to determine the basline for the fitted curve. The parameter is used to define the cut off point for the curve fit (proportion of peak height) used to eliminate recirculation effects. The parameter is used to define the interval over which excess of data due to recirculation is estimated.
The region fit button can be used to estimate and from all of the data within a region defined by a binary mask stored on the top of the imcalc stack. This should be done prior to regional analysis.