Problems with Siemens Skyra 3T for MRS

Hi I have been having some problems with our scanner and I was wondering if these were site specific or if anyone else has run into similar problems and if there were ways to solve them.

Problem 1:
I did a measurement today trying out a pain/heat paradigm. I did the measurements so that I averaged 16 spectra for each “timepoint” and I took 6 “timepoints” per scenario (so each scenario had 6x16 spectra). I noticed that after 4 “timepoints” I would need to do the shimming again due to the spectra having a huge water spike. Is this typical? If the voxel placement and size stay the same and the participant is very still is there a recomended timeinterval for when to redo the shimming and frequency adjustments? The timepoints were taken directly after one another, within a 5min time span for each scenario.

Problem 2:
Our scanner’s software is having trouble reconstructing the MRS data. It is totally random when it does the reconstuction and when it doesn’t. When it doesn’t do the reconstuction it shows: ↯ (a downwards zigzag arrow). I then have to do a RetroRecon to get the data. And even this doesn’t always work. It might take 4-7 tries to get it to work.

Problem 3:
When I try to copy parameters from a sequence to another it only copies the saturation regions, but not the voxel position. So instead of having a ready to go program that I just have to copy parameters from the previous sequence, I need to “reuse and open” the previous to get the same voxel placement and then change the other parameters that I want.

Has anyone else had the same problems?

to problem 1:
Normally, a shim should be stable for more than 2 minutes. How did you measure these 6 timepoints (e.g. 6 different measurements in a row, 1 measurement with 6 measurements in the contrast->dynamic card or 1 measurement with 96 averages saved separately and averaged manually)? In which brain region did you measure? What was your bandwith for VAPOR water suppression?

to problem 2:
I know problems for reconstruction and saving (for VE11E) when I use save single averages and a higher amount of averages. This is one reason why I use the CMRR package for spectroscopy at our Siemens scanner. Would it function when you use only a less number of averages (e.g. 16)?

to problem 3:
which parameters have you copied? For voxel position, try ‘copy parameters’ → ‘measurement parameters’. Then the voxel position should be right. But I’m not sure, if the voxel lengths will be copied.


In my program for one scenario (for example apply heat or no heat) I had 6 sequences with each having 16 averages. And I would just manually press them on one after another. Each sequence took about 42sec. I was in the ACC. I am not too good at the water suppression yet, so I didn’t know what to put as a bandwidth, so it was the one that Siemens had as a default.

I only had 16 averages for each. I have also tried with 8 and that didn’t go through either, or sometimes it does and sometimes it doesn’t it seams very random and I haven’t found a pattern yet to when it does and when it doesn’t do the reconstuction. I will take a look at that CMRR package it looks very promising.

I did the ‘copy parameters’ → and the highest option that is supposed to copy everything. I can’t remember the name now, since I am not at the scanner right now. But I do remember it was a longer sentence than ‘measurement paramters’ so I will try that next time.