imglhki 1.3.1 © 2002-2012 by Turku PET Centre
Estimation of influx rate constant (Ki) from dynamic PET images in
ECAT 6.3 or 7.x format applying Lawson-Hanson non-negative least squares
(NNLS) [1] to solve general linear least squares functions.
Ki is estimated directly without division [2] from one- or two-tissue
compartment model.
Parameters:
1) Plasma file (times in minutes!)
2) Dynamic image file
3) Parametric image file
e.g.: imglhki ua2918ap.kbq ua2918dy1.v ua2918ki.v
Options for model selection:
-A Automatic selection of model for separate pixels
-1 Force one-tissue compartment model for all pixels
-2 Force two-tissue compartment model for all pixels
-0 Akaike weighted average of 1- and 2-tissue
compartment model results [3] (default)
-M Selected model is written as second 'frame' in the parametric image.
Other command line options:
-T=<threshold%>
Pixels with AUC less than (threshold/100 x plasma AUC) are set to zero.
default is 0%
-E=<Fit end time (min)>
Use data from 0 to end time; by default, model is fitted to all frames.
-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 unit of pixel values in the parametric image is ml/(min*ml).
References:
1. Lawson CL & Hanson RJ. Solving least squares problems.
Prentice-Hall, 1974.
2. Zhou Y, Brasic J, Endres CJ, Kuwabara H, Kimes A, Contoreggi C, Maini A,
Ernst M, Wong DF. Binding potential image based statistical mapping for
detection of dopamine release by [11C]raclopride dynamic PET.
NeuroImage 2002;16:S91.
3. Turkheimer FE, Hinz R, Cunningham VJ. On the undecidability among
kinetic models: from model selection to model averaging. J Cereb Blood
Flow Metab 2003; 23: 490-498.
See also:
imgki,
ecat2tif,
lhsolki,
patlak
Keywords: image, modelling, influx rate, NNLS
This program comes with ABSOLUTELY NO WARRANTY. This is free software, and
you are welcome to redistribute it under GNU General Public License.