Hi Georg,
I’m so impressed by the high-quality comments you’ve provided! We contacted the MRI center and made the changes according to your suggestion immedialtely!
Majr changes are made:
Water reference:
1 set the water suppression to “RF off” instead of “None” and set the water suppression B.W to 35 Hz (we should make it consistent for both MEGA-PRESS and PRSS).
2 set the delta frequency for both MEGA-PRESS and PRESS water reference to 0 ppm.
3 decrease the numbers of water avearges and the preparation scans.
MEGA-PRESS
1 set the edit bandwidth to 47 Hz instead of 70 (this is the lowest avaliable option now)
2 set the delat frequency to -1.7 ppm.
3 increase the voxel size to 2.72.72.7 cm^3 (almost 20 ml).
Additionally, I’ve uploaded the short TE PRESS sequence now and am really looking forward to receiving your feedback. The default delta frequency in PRESS is -2.3 ppm. I’m not sure should we change to.
SO_AC_049[Allen Cheong]64 _new.pdf (60.8 KB)
By the way, would it be possible for you to share a Siemens 3T scanning PDF for the GABA-edited MEGA-PRESS sequence? Although I’ve carefully marked all the messages you’ve mentioned, I’m concerned that I might overlook some other key points.
Thank you so much for your invaluable assistance, your time and your selflessness truly shines through. We are definitely planning to implement the revised protocol and will keep you updated on its performance.
Cheers,
Melinna