Thank you for the clarification! A quick follow up question. Do you know of any systematic comparison of:
1) standard fieldmap (two pairs of phase and magnitude images) 2) fieldmap derived from a pair of spin echo images with opposite phase encoding directions 3) fieldmap derived from a pair of gradient echo images with opposite phase encoding directions (for example the reference images - SBRef) ? Best regards, Chris On Mon, Oct 5, 2015 at 4:04 PM, Harms, Michael <[email protected]> wrote: > > Yes, that is correct. (The SBRef for the BOLD scans are gradient-echo > images). > > -- > 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: Chris Filo Gorgolewski <[email protected]> > Date: Monday, October 5, 2015 5:13 PM > To: Hcp Users <[email protected]> > Subject: [HCP-Users] Use of spin-echo EPI scans for distortion correction > of fMRI data > > Hi, > After reading the preprocessing scripts (see > https://github.com/Washington-University/Pipelines/blob/master/fMRIVolume/scripts/DistortionCorrectionAndEPIToT1wReg_FLIRTBBRAndFreeSurferBBRbased.sh#L271) > and the paper (see > http://www.sciencedirect.com/science/article/pii/S1053811913005053) I > figured that HCP is using a pair of spin-echo EPI scans to estimate a > fieldmap later used to correct fMRI data for distortions (in contrast to > using a pair of SBRef images). We had a bit of a discussion in the lab > about this and I just wanted someone from the HCP team to confirm this. > Thanks in advance! > > Best, > Chris > > _______________________________________________ > 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
