fit_h2o 4.2.0 © 1999-2013 by Turku PET Centre
Non-linear fitting of one-tissue compartmental water model to PET [O-15]H2O
study data.
The model parameters are blood flow (F), partition coefficient (pWater),
arterial blood volume (Va) and time delay (delayT). Venous radioactivity
is assumed to be the same as the tissue concentration.
Extraction factor of water is assumed to be 1.0.
The blood flow obtained using PET [O-15]H2O techniques reflects tissue
perfusion, since the method is dependent on the tissue exchange of
labelled water. Non-nutritive flow (blood flowing through arteriovenous
shunts) is not measured (Lammertsma & Jones, 1983).
Command line parameters:
1) Blood H2O file
2) Tissue TAC file (*.dft or *.tac)
3) Fit duration (sec)
4) Result file
Options:
-ml or -dl
In results the units of F and Va will be given per mL or per dL,
respectively. By default, units are per dL.
-fpt
Blood flow (perfusion) is reported per perfusable tissue volume
(PET volume minus vascular volume). By default perfusion is reported
per PET volume.
-input=<File name for new time delay corrected blood TAC>
Input TAC sample times are corrected by the median of fitted time
delay values; resulting input file can be used with imgflow, or
as input to this program to have common time delay for all regions.
-i=<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.
Parameter can be fixed to a certain value by setting its
lower and upper limit to that value.
-SD[=<y|N>]
Standard deviations are calculated and saved in results (y), or
not calculated (n).
-CL[=<y|N>]
95% Confidence limits are calculated and saved in results (y), or
not calculated (n).
-Va=<Va(%)>
Enter a fixed Va; fitted by default.
-Delay=<Time delay (s)>
Enter a fixed time delay; fitted by default.
-pH2O=<Partition coefficient for water>
Enter a fixed pH2O; fitted by default.
-svg=<Filename>
Plots of original and fitted TACs are written in specified file in
Scalable Vector Graphics (SVG) 1.1 format; specification in
http://www.w3.org/TR/SVG/
-fit=<Filename>
Fitted regional TACs are written in DFT format.
-resid=<Filename>
Weighted residual curves are written in DFT format.
-h or --help
Print this message and exit
-v, --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.
Example: fit_h2o uo1234bl.kbq uo1234.dft 999 uo1234f.res
Times must be in seconds in all PET data files.
References:
1. Lammertsma AA, Jones T. J Cereb Blood Flow Metab. 1983;3:416-424.
See also:
b2t_h2o,
imgflow,
arlkup,
water_input,
fitk2
Keywords: DFT, modelling, perfusion, blood flow
This program comes with ABSOLUTELY NO WARRANTY. This is free software, and
you are welcome to redistribute it under GNU General Public License.