lhsol - tpcclib 0.8.0 © 2023 by Turku PET Centre

Fitting of full or reduced compartmental model to plasma and tissue
time-activity curves (PTAC and TTAC) to estimate the model parameters.
 
  ____        ____        ____        ____                             
 | Cp |--K1->| C1 |--k3->| C2 |--k5->| C3 |  compartments in series (s)
 |____|<-k2--|____|<-k4--|____|<-k6--|____|                            
 
              ____        ____  
  ____       |    |--k3->| C2 |            compartments in parallel (p)
 |    |--K1->|    |<-k4--|____| 
 | Cp |      | C1 |       ____  
 |____|<-k2--|    |--k5->| C3 | 
             |____|<-k6--|____| 
 
Compartmental models are transformed into general linear least squares
functions (1, 2, 3, 4), which are solved using Lawson-Hanson linear
least-squares algorithms (5). Note that rate constants and macroparameters
are represented per volume (as measured by PET) including vascular volume.
 
Usage: lhsol [options] PTAC TTAC fittime results
 
Options:
 -model=<k1 | k2 | k3 | k4 | k5s | k6s | k5p | k6p>
     representing the following compartmental model settings:
     k1 (for assuming k2=k3=k4=k5=k6=0)
     k2 (for assuming k3=k4=k5=k6=0)
     k3 (for assuming k4=k5=k6=0)
     k4 (for assuming k5=k6=0); default
     k5s (for assuming k6=0 and compartments in series)
     k6s (compartments in series)
     k5p (for assuming k6=0 and compartments in parallel)
 -Vp=<ignored|fitted>
     Vascular volume is ignored (default) or fitted; note that PTAC is
     assumed to represent vascular blood curve.
 -w1 | -wf
     Sample weights are set to 1 (-w1) or to frame lengths (-wf);
     by default weights in TTAC file are used, if available.
 -svg=<Filename>
     Fitted and measured TACs are plotted in specified SVG file.
 -fit=<Filename>
     Fitted regional TTACs are written in specified file.
 -lp=<Filename>
     Parameters of linear model are saved in specified 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.
 
References:
1. Blomqvist G. On the construction of functional maps in positron emission
   tomography. J Cereb Blood Flow Metab 1984;4:629-632.
2. Gjedde A, Wong DF. Modeling neuroreceptor binding of radioligands
   in vivo. In: Quantitative imaging: neuroreceptors, neurotransmitters,
   and enzymes. (Eds. Frost JJ, Wagner HM Jr). Raven Press, 1990, 51-79.
3. Oikonen V. Multilinear solution for 4-compartment model:
   I. Tissue compartments in series.
   http://www.turkupetcentre.net/reports/tpcmod0023.pdf
4. Oikonen V. Multilinear solution for 4-compartment model:
   II. Two parallel tissue compartments.
   http://www.turkupetcentre.net/reports/tpcmod0024.pdf
5. Lawson CL & Hanson RJ. Solving least squares problems.
   Prentice-Hall, 1974.
 
See also: fitk4, fitk5, patlak, logan, imglhdv, fitdelay, taccbv
 
Keywords: TAC, modelling, compartmental model, LLSQ