Analyze two-tissue compartment model with this program. fitk3 help you with the non-linear fitting of two-tissue compartment model to plasma and tissue time-activity curves (TACs) to estimate K1, k2, k3, and optionally Vb.

Parameters:
1) Plasma file (corrected for labeled metabolites)
2) Blood file
3) Tissue TAC file (*.dft)
4) Fit time (in minutes from injection)
5) Result file

Options:
-lim[=<filename>]
Specify the constraints for model parameters; This file with default values can be created by giving this option as the only command-line argument to this program. Without filename the default values are printed on screen.
-SD[=<y|N>]
Standard deviations are calculated and saved in results (y), or not calculated (N, default). Program runs a lot faster if SD and CL are not calculated.
-CL[=<y|N>]
95% Confidence limits are calculated and saved in results (y), or not calculated (N, default).
-Vb=<Vb(%)>
Enter a fixed Vb; fitted by default.
-r=<Reference region name or filename>
Optional reference region is used to constrain K1/k2 in other regions; Also k3 is fitted to reference region data, thus any large region (for example cortex) can be used here.
-fit=<Filename>
Fitted regional TACs are written in DFT format.
-svg=<Filename>
Fitted and measured TACs are plotted in specified SVG file.
-h or --help
Print this message and exit.
--version or --build
Print software build information and exit.
--silent
Program works silently, printing only error and warning messages.
--verbose
Program prints more information about what it is doing.

The license of this software is Freeware, you can free download and free use this calculator software.