fit_srtm - tpcclib 0.7.8 © 2022 by Turku PET Centre

NLLSQ estimation of R1 (=K1/K1'), k2 and, BPnd (binding potential) using
simplified reference tissue compartment model, SRTM (1,2,3).
Assumptions are that K1/k2 is the same in all brain regions, and that 
1TCM with plasma input could fit the tissue curves satisfactorily.
 
Usage: fit_srtm [Options] ttacfile reference endtime resultfile
 
TTAC file can be in DFT or PMOD format. Sample times must be in minutes.
If TTAC file contains weights, those are used in the NLLSQ fitting.
Reference region TAC can be given separate TAC file or as the name or number
of the reference region in TTAC file.
 
Options:
 -DVR
     Instead of BPnd, program saves the DVR (=BPnd+1) values.
 -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.
 -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).
 -w1
     All weights are set to 1.0 (no weighting); by default, weights in
     TTAC file are used, if available.
 -wf
     Weight by sampling interval.
 -fit=<Filename>
     Fitted regional TACs are written in 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.
 
 
Values of R1, k2, k2', and BPnd are written in the specified result file.
Fitted curves are written in DFT format, if file name is given.
 
Example 1: file a789.tac contains regions-of-interest and reference region,
with name 'cereb all'. The whole time range is used in the fit.
     fit_srtm a789.tac 'cereb all' 999 a789.res
 
Example 2: Reference region TAC is in a separate file, a789ref.tac;
standard deviations and confidence limits are also estimated.
     fit_srtm -SD=y -CL=y a789.tac a789ref.tac 999 a789.res
 
References:
1. Cunningham VJ, Hume SP, Price GR, Ahier RG, Cremer JE, Jones AKP.
   Compartmental analysis of diprenorphine binding to opiate receptors
   in the rat in vivo and its comparison with equilibrium data in vitro.
   J Cereb Blood Flow Metab 1991;11:1-9.
2. Lammertsma AA, Hume SP. Simplified reference tissue model for PET
   receptor studies. Neuroimage 1996;4:153-158.
3. Oikonen V, Sederholm K. TPCMOD0002: Model equations for reference tissue
   compartmental models. http://www.turkupetcentre.net/reports/tpcmod0002.pdf
 
See also: bfmsrtm, tacweigh, rescoll, logan, fit_frtm, sim_rtcm
 
Keywords: TAC, modelling, binding potential, SRTM, reference input