Difference between Siemens TWIX .dat file and .dat file


I’m new to the MRS study and have a naive question about the Siemens .dat file. I wonder what the difference is between .dat files exported from TWIX and non-TWIX. Because the technician instructed us to export .dat data one way from the TWIX interface and another way not through the TWIX interface.

I can’t load our data by Gannet or Osprey at the moment. I learned from another post, it’s probably because we are using the new Siemens Syngo System.

Thank you.

TWIX (.dat files) contain the raw data ‘at their rawest’, i.e. before receiver-coil combination.

The other Siemens-proprietary format is RDA (.rda files), which contains data that has undergone various levels of inline pre-processing on the scanner - at least coil combination, but also sometimes averaging of individual transients, depending on software version and exam card parameters.

Finally, most sequences also allow data to be exported directly in an enhanced DICOM format.

Which software version does your system run? I think @Helge just added XA31 support to Osprey a few minutes ago…

Thanks for your reply. I have tried the .rda files and have seen that they are time-averaged.

Happy to hear the good news! We are using syngo MR XA30 system. Is that also applicable?

Hi @gunziyu,

I’ve the export worked correctly, I’d believe that the loader works for your data. However, I did only test it on stock PRESS and HERCULES universal sequence data, so it is possible that is not working for your data. If it is not working with the most recent version on GitHub you would have to share the data with us so that we can take a look at the issue.


Hi Helge,

I have tried but failed to load our data. We use Siemens MEGA-PRESS svs_edit sequence, maybe it’s the problem. I’ve sent a message to you including a link to the data. Very grateful if you could take a look. Thank you.

Hi @gunziyu,

I’ve just updated the Osprey loader to support XA30 data acquired with the svs_edit WIP. You can download the latest develop-branch (GitHub - schorschinho/osprey: All-in-one toolbox for processing of magnetic resonance spectroscopy data.) and test it with your data.


Hi Heldge,

Many thanks for your help, it works well.

Sorry for taking so long to reply. It took some time for me to figure out how to process the data without GUI – the GUI didn’t work but I have learnt from another post that that’s because I’m running on Windows and there was a ‘/’ error. Now both GUI and non-GUI codes work good. Thank you.