PMOD CRV file format
Data is organized in columns, separated by a single tabulator character. Thus, PMOD CRV files are in TSV format. CRV file contain a single title line, followed by numerical data. Decimal point should be used as decimal separator, although both decimal point and comma are supported by TPCCLIB software.
The title line specifies the column names. Time units (minutes, seconds, hours) are specified in square brackets immediately after the name of the first column title, and TAC value units are similarly given immediately after the name of the second column.
File name extension should be
.crv. By convention, extensions
.tac are also used for tissue and blood TAC data, respectively.
PET and ABSS radioactivity
is measured during a time frame, and each sample point in the
TAC represents the average radioactivity concentration during that frame. Commonly the TAC data is
saved with only the mid frame time, but further calculations can be done with
better precision if both frame start and end times are stored in the TAC file.
In PMOD CRV the frame start and end times can be saved as the two first columns, with titles
end, respectively. The time and concentration units, if
available, are given in these titles, respectively.
As an example, the regional TACs of cerebellum and right and left striatum in a [11C]Raclopride PET study are given below in PMOD CRV (TAC) format:
start[minutes] end[kBq/cc] Cerebellum striatum dx striatum sin 0.00 1.00 3.193e+00 3.624e+00 3.506e+00 1.00 2.00 5.513e+00 6.538e+00 6.119e+00 2.00 3.00 5.402e+00 7.411e+00 8.394e+00 3.00 4.00 5.025e+00 7.397e+00 7.793e+00 4.00 5.00 5.330e+00 8.448e+00 7.867e+00 5.00 6.00 5.170e+00 8.037e+00 9.793e+00 6.00 7.00 4.618e+00 9.724e+00 8.994e+00 7.00 8.00 4.595e+00 8.382e+00 9.098e+00 8.00 9.00 4.211e+00 9.623e+00 8.962e+00 9.00 10.0 4.386e+00 1.005e+01 8.510e+00 10.0 11.0 4.259e+00 8.642e+00 9.859e+00 11.0 12.0 4.248e+00 9.874e+00 1.060e+01 12.0 13.0 4.002e+00 1.015e+01 9.235e+00 13.0 14.0 4.005e+00 8.660e+00 9.003e+00 14.0 15.0 3.868e+00 9.943e+00 8.138e+00 15.0 17.0 3.814e+00 9.683e+00 8.814e+00 17.0 19.0 3.576e+00 9.297e+00 8.926e+00 19.0 21.0 3.589e+00 9.755e+00 9.483e+00 21.0 23.0 3.363e+00 9.456e+00 9.612e+00 23.0 25.0 3.345e+00 8.644e+00 1.021e+01 25.0 27.0 3.300e+00 9.341e+00 9.224e+00 27.0 29.0 3.116e+00 8.931e+00 8.699e+00 29.0 34.0 3.333e+00 9.569e+00 8.775e+00 34.0 39.0 3.145e+00 9.596e+00 8.943e+00 39.0 44.0 3.088e+00 8.813e+00 8.892e+00 44.0 49.0 2.925e+00 8.509e+00 8.976e+00 49.0 54.0 2.731e+00 8.256e+00 7.552e+00 54.0 60.0 2.883e+00 8.593e+00 8.372e+00
Blood and plasma TACs measured with manual blood sampling have only a single time column. ABSS blood data is usually collected with very short frame durations, and therefore that is also stored with a single time column, representing the mid times of frames. PET image-derived input data should be stored with frame start and end times.
The title of the sample time column in PMOD CRV format is
time, immediately followed
by the units in square brackets. The following column has title
parent-fraction, immediately followed by the units of the
concentrations in square brackets, or
[1/1] in case of unitless
The file could also include more concentration columns with appropriate column titles, but programs
processing input data often assume that only one concentration column is present.
As an example, the plasma TAC, based on arterialized venous blood sampling, in a [18F]FDG PET study is given below in PMOD CRV (BLD) format:
time[minutes] plasma[kBq/cc] 0.333 3.2220e+00 0.850 3.3467e+01 1.233 1.9928e+01 1.667 1.6322e+01 2.050 1.4923e+01 3.250 1.2470e+01 5.367 9.9100e+00 9.117 6.6850e+00 19.000 3.0710e+00 24.367 2.2770e+00 29.083 1.7530e+00 34.017 1.3990e+00 49.300 7.2500e-01 69.100 4.5500e-01 82.967 3.5400e-01
- DFT format
- Units of radioactivity in PET data
- Radioactivity measurement of blood samples
- PET data
- Simulation of PET time frames
- Plotting TACs
Updated at: 2019-11-21
Created at: 2019-11-21
Written by: Vesa Oikonen