fit_mo2 3.0.0 © 1998-2008 by Turku PET Centre
Fits the following compartmental model dedicated for skeletal muscle (1, 2, 3)
to regional PET [O-15]O2 study data.
The model parameters are perfusion (Flow, K1), oxygen extraction ratio
(OER = K1/(k2+k3)), partition coefficients of oxygen and water (K1/k2 and
pH2O), blood volume fraction (Vb) and time delay (delayT).
Blood Muscle
_______________________________________
| K1 | |
| O ----------> O + O -Mb |
| 2 <---------- 2 2 |
| k2 |
| | | k3 |
| | V |
| K1 | |
| H O ----------> H O |
| 2 <---------- 2 |
| | K1/pH2O |
|______________|________________________|
Model definitions:
K1=Flow (mL/min/dL), OER=k3/(k2+k3),
Ki=Flow*OER (mL/min/dL),
Metabolic rate of oxygen MRO2=Ki*[O2]a (mmol/min/dL)
Command line arguments:
1) Blood O2 TAC file
2) Blood H2O TAC file
3) Muscle TAC file (*.dft)
4) Fit duration (sec)
5) Result file
General options:
-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).
-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.
-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 lots of information about what it is doing
Options to set model parameters:
-cO2a=<Arterial O2 concentration>
Set the O2 content (mL O2/100 mL blood) of arterial blood to calculate
rMRO2, for example -cO2a=19.8;
if not specified, program can calculate only Ki for [O-15]O2
-Af=<Arterial proportion (%)>
Set the simulated arterial proportion of total blood volume;
default is 30%
Options for constraining model parameters:
-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.
-Vb=<Blood volume (%)>
Set the regional blood volume; default is 3.5%
-pH2O=<value>
Set the partition coefficient of water; default is 0.99
-Flow=<value>
Set the regional perfusion (blood flow) value, e.g. based on [O-15]H2O
study, in units mL/100mL/min
-fK1k2
K1/k2 for oxygen is not estimated as a free parameter, but it is
calculated from OER and saturation curves for hemoglobin and myoglobin
-K1k2=<value>
Specify the K1/k2 for oxygen.
-Sao2=<value>
Saturation of arterial blood hemoglobin; default is 0.97
-p50Hb=<value>
Half-saturation pressure for hemoglobin; default is 3.6 kPa
-p50Mb=<value>
Half-saturation pressure for myoglobin; default is 0.319 kPa
-nHb=<value>
Hill coefficient for hemoglobin; default is 2.7
-Mb=<value>
Concentration of myoglobin in muscle; default is 4.7 mg/g
-Hb=<value>
Concentration of hemoglobin in blood; default is 150 mg/g
Example: fit_mo2 uo1235_o.kbq uo1235_w.kbq uo1235.dft 999 uo1235mo2.res
Times must be in seconds in all data files. File format is specified in
http://www.turkupetcentre.net/analysis/doc/format_dft.html
References:
1. Nuutila P, Peltoniemi P, Oikonen V, Larmola K, Kemppainen J, Takala T,
Sipila H, Oksanen A, Ruotsalainen U, Bolli GB, Yki-Jarvinen H.
Enhanced stimulation of glucose uptake by insulin increases
exercise-stimulated glucose uptake in skeletal muscle in humans: studies
using [15O]O2, [15O]H2O, [18F]fluoro-deoxy-glucose, and positron emission
tomography. Diabetes 2000; 49:1084-1091.
2. Oikonen V, Nuutila P, Sipilä H, Tolvanen T, Peltoniemi P, Ruotsalainen U.
Quantification of oxygen consumption in skeletal muscle with PET and
oxygen-15 bolus. Eur J Nucl Med. 1998; 25: 1151.
3. Oikonen V. Modelling of low oxygen consumption. In: J. Knuuti, J. Rinne,
P.Tenhonen (ed.), Medical Applications of Cyclotrons VIII. Abstracts of
the VIII Symposium on the Medical Applications of Cyclotrons.
Annales Universitatis Turkuensis D346:16, 1999.
See also:
o2metab,
o2_p2w,
fit_o2bl,
b2t_mo2,
rescoll
Keywords: DFT, modelling, oxygen, skeletal muscle
This program comes with ABSOLUTELY NO WARRANTY. This is free software, and
you are welcome to redistribute it under GNU General Public License.
