fitk3 - tpcclib 0.8.0 © 2023 by Turku PET Centre
Non-linear fitting of two-tissue compartment model to plasma input, blood,
and tissue time-activity curves (PTAC, BTAC, and TTAC) to estimate
parameters K1, k2, k3, and Vb. Sample times must be in minutes.
______ ___________________
| | K1 | k3 |
| | --> | -------> |
| Ca | <-- | C1 <------- C2 |
| | k2 | k4=0 |
|______| |___________________|
Usage: fitk3 [Options] ptacfile 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.
-r=<Reference region id 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, --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.
Example 1: estimate K1, K1/k2, k3 and Vb
fitk3 ua919ap.bld ua919ab.bld ua919.tac 60 ua919k3.res
Example 2: estimate K1 and k3; Vb is constrained to 4.5% and K1/k2 is
constrained to K1/k2 estimated from region 'occip'
fitk3 -Vb=4.5 -r=occip ua919ap.bld ua919ab.bld ua919.tac 60 ua919.res
See also: patlak, lhsol, p2t_v3c, tacweigh, taccbv, rescoll
Keywords: TAC, modelling, irreversible uptake, k3, Ki, 2TCM