Hi Michael Any idea on where my aliasing could be coming from? Here is a link to the data file in case it's useful to see.
https://dl.dropboxusercontent.com/u/3889124/14-1-1dMRIseq1APcmrr.nii.gz thanks, Mark On Mon, Nov 23, 2015 at 9:23 PM, Mark A. Pinsk <[email protected]> wrote: > Excite pulse duration: 2560 us > Refocus pulse duration: 5120 us > Single band images: off > MB LeakBlock Kernel: off > MB RF phase scramble: off > Time-shifted MB RF: off > SENSE1 coil combine: ON > Log physiology to file: off > Invert RO/PE polarity: off > Online multi-band recon: Online > FFT scale factor: 1.00 > > > > On Mon, Nov 23, 2015 at 6:29 PM, Harms, Michael <[email protected]> wrote: > >> >> What are your settings on all the parameters on the Sequence:Special tab? >> >> -- >> Michael Harms, Ph.D. >> ----------------------------------------------------------- >> Conte Center for the Neuroscience of Mental Disorders >> Washington University School of Medicine >> Department of Psychiatry, Box 8134 >> 660 South Euclid Ave. Tel: 314-747-6173 >> St. Louis, MO 63110 Email: [email protected] >> >> From: "Mark A. Pinsk" <[email protected]> >> Date: Monday, November 23, 2015 10:39 AM >> To: "[email protected]" <[email protected]> >> Subject: [HCP-Users] aliasing in diffusion images >> >> Hi all, >> >> I've attempted to collect diffusion data with the CMRR sequence at our >> Prisma, and got aliasing in the image (very apparent at higher b value). >> Snapshot here: >> https://dl.dropboxusercontent.com/u/3889124/b2500-MB3.tiff >> >> Any suggestions on what the issue(s) could be? >> I see the same when I lower MB from 3 to 2. >> >> Here are my protocol parameters: >> 64-channel head/neck coil >> 90 interleaved transverse slices >> in-plane resolution = 1.5mm >> slice thickness = 1.5mm with no inter-slice gap >> field of view (FOV) = 210mm >> base resolution = 140 >> repetition time (TR) = 4200ms >> echo time (TE) = 87ms >> flip angle (FA) = 78 deg >> refocus FA = 160 deg >> phase partial fourier (PPF) = 6/8 >> gradient reversed fat suppression >> phase encode (PE) direction = anterior/posterior >> bandwidth = 1880Hz/Px >> echo spacing (ES) = 0.71ms >> multiband acceleration factor = 3 >> SENSE (R=1) image reconstruction >> bmax = 2500 s/mm^2 >> >> >> thanks! >> Mark >> >> _______________________________________________ >> HCP-Users mailing list >> [email protected] >> http://lists.humanconnectome.org/mailman/listinfo/hcp-users >> >> >> ------------------------------ >> >> The materials in this message are private and may contain Protected >> Healthcare Information or other information of a sensitive nature. If you >> are not the intended recipient, be advised that any unauthorized use, >> disclosure, copying or the taking of any action in reliance on the contents >> of this information is strictly prohibited. If you have received this email >> in error, please immediately notify the sender via telephone or return mail. >> > > _______________________________________________ HCP-Users mailing list [email protected] http://lists.humanconnectome.org/mailman/listinfo/hcp-users
