QView CSV format

QView software from QSPECT project in Osaka saves regional tissue time-activity curves (TTACs) in a specific CSV format. Example of an QView data file:

directory,file name,num,slice,mean,sd,cov,max,min,pixel,total,group

The third column (num) tells the number of ROI, and the number of time frame in parenthesis. The fourth column (slice) contains the image plane number.

Notice that lines may not be ordered numerically, but alphabetically.

ROI groups

QView can also calculate and save the means of selected ROIs as 'group'; in that case, the data of those group TACs are in the end of the CSV file, the ROI number in the 3rd column and the slice number in 4th column are missing, and the last column (group) that may otherwise be empty will contain the group name.

Frame times

QView CSV files do not contain the frame times, only the frame numbers. Time information can be retrieved and saved from PET images in SIF format, and added to the TTAC data after it has been converted to other file formats that support time information, such as PMOD CRV or TPC DFT.

Conversion to other formats

Because of the missing frame time information, original QView CSV files cannot be used by analysis and modelling software as such, but need to be converted to other formats.

Program tacformat, starting from version 0.6.17, can read QView CSV file, and save it in certain other formats. For example, to convert file us956_kidney_left.csv to PMOD format (with extension .tac), and to add time frame information from SIF, you would enter the following commands:

tacformat -f=pmod us956_kidney_left.csv
tacframe us956_kidney_left.tac us956dy1.sif

Radioactivity concentration units are also missing. If needed, program tacunit can be used to set the correct units to the converted file, for example:

tacunit -yset=Bq/mL us956_kidney_left.tac

See also:

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Updated at: 2019-12-21
Created at: 2017-10-12
Written by: Vesa Oikonen