fitk4di - tpcclib 0.8.1 © 2025 by Turku PET Centre
Non-linear fitting of dual input compartment model, with one tissue
compartment for each input (parent tracer and its labelled metabolite):
_____ K1p ______ k3p ______
| Cap | ----> | Ct1p | ----> | Ct2p |
|_____| <---- |______| <---- |______|
k2p k4p
_____ K1m _____
| Cam | ----> | Ctm |
|_____| <---- |_____|
k2m
Note that the model may be too complex to provide reliable parameter
estimates in most practical use cases.
Usage: fitk4di [Options] ptacfile mtacfile btacfile ttacfile endtime resultfile
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.
If Vb (vascular blood volume) is pre-corrected or to be ignored, set
it to 0; btacfile can be set to 'none'.
-mc=<Filename>
Fit-based metabolite corrected regional TACs are written in the file.
-fit=<Filename>
Fitted regional TACs are written in the file.
-svg=<Filename>
Fitted and measured TACs are plotted in specified SVG file.
-h, --help
Display usage information on standard output and exit.
-v, --version
Display version and compile information on standard output and exit.
-d[n], --debug[=n], --verbose[=n]
Set the level (n) of debugging messages and listings.
-q, --quiet
Suppress displaying normal results on standard output.
-s, --silent
Suppress displaying anything except errors.
Sample times must be in minutes.
Example: fitting with default settings
fitk4di ia919apc.kbq ia919apm.kbq ia919ab.kbq ia919.dft 60 a919k4di.res
See also: fitk2di, fitk2, fitk4, sim_3tcm, tacweigh, taccbv
Keywords: TAC, modelling, distribution volume, dual-input