imgdv - tpcclib 0.7.5 © 2020 by Turku PET Centre

Calculates the distribution volume (Vt, DV) or distribution volume ratio (DVR)
from dynamic PET image in ECAT, NIfTI-1, or Analyze 7.5 format,
applying the multiple time graphical analysis (MTGA) approach for reversible
tracer uptake (Logan plot) (1, 2, 3).
Simple non-iterative perpendicular line fitting algorithm (4) is applied
in determination of the slope of the Logan plot.
 
Usage: imgdv [Options] input image starttime resultimage
 
Input can be either a TAC file containing arterial plasma PTAC or reference
region TTAC. Data must be in the same concentration units as the data in
image, and times in min; however, if units are specified inside the input
and image file, the program can automatically convert units.
Start time of the linear fit must be given in minutes; set to zero to
let the program automatically determine the start time (not recommended).
 
Options:
 -k2=<k2 of reference region>
     With reference region input it may be necessary to specify also the
     population average for reference region k2 (2).
 -thr=<threshold%>
     Pixels with AUC less than (threshold/100 x input) are set to zero.
     Default is 0 %.
 -max=<Max value>
     Upper limit for Vt or DVR values; by default max is set pixel-wise
     to 10 times the AUC ratio.
 -min=<Min value>
     Lower limit for Vt or DVR values; 0 by default.
 -filter
     Remove parametric pixel values that are over 4x higher than
     their closest neighbours.
 -end=<Fit end time (min)>
     By default line is fitted to the end of data. Use this option to enter
     the fit end time.
 -v=<filename>
     Y axis intercepts times -1 are written as an image in specified file.
 -n=<filename>
     Numbers of selected plot data points are written as an image.
 -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:
     imgdv ua3818ap.kbq ua3818dy1.v 20 ua3818dv.v
 
The unit of pixel values in the parametric Vt image is
(mL plasma)/(mL tissue). Data in DVR image are unitless.
 
In theory, DVR equals BPnd+1, and therefore a binding potential image can
be computed from DVR image by subtraction of unity, e.g. using program
imgcalc. However, this may lead to a large number of pixels with negative
values that may hamper the further statistical or visual analysis.
 
References:
1. Logan J, Fowler JS, Volkow ND, Wolf AP, Dewey SL, Schlyer DJ,
   MacGregor RR, Hitzemann R, Bendriem B, Gatley SJ, Christman DR.
   Graphical analysis of reversible radioligand binding from time-activity
   measurements applied to [N-11C-methyl]-(-)-cocaine PET studies in human
   subjects. J Cereb Blood Flow Metab 1990; 10: 740-747.
2. Logan J, Fowler JS, Volkow ND, Wang GJ, Ding YS, Alexoff DL.
   Distribution volume ratios without blood sampling from graphical
   analysis of PET data. J Cereb Blood Flow Metab. 1996; 16: 834-840.
3. Logan J. Graphical analysis of PET data applied to reversible and
   irreversible tracers. Nucl Med Biol 2000; 27:661-670.
4. Varga J & Szabo Z. Modified regression model for the Logan plot.
   J Cereb Blood Flow Metab 2002; 22:240-244.
 
See also: imgbfbp, imglhdv, img2tif, logan, imgki, imgcalc
 
Keywords: image, MTGA, Logan plot, modelling, Vt, DVR, distribution volume