Were these oblique acquisitions? By default, dcm2nii and MRIConvert rotate the bvecs according to the orientation info for oblique acquisitions, whereas it sounds like mri_convert might not be doing that.
cheers, -MH -- 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: mha...@wustl.edu On 9/12/13 9:23 AM, "P Taylor" <neon.tay...@gmail.com> wrote: >Hello, > >I have a question about using mri_convert on diffusion *.dcm files. >When extracted, the gradient table is different than that given by >either MRIConvert (from the UCLA-LCNI webpage) or than dcm2nii of >MRICron; NB: the latter give the *same* results. The differences in >gradient are also not simply sign changes, unfortunately (though, >there is that issue as well, since many x- and y- gradients of >mri_convert are close to the others, but the z-gradient appears to be >uniformly oppositely signed). >This is coupled with the fact that often both the orientation is >different (noted in previous entries), as well as the ORIGIN >information being different. > >Is there any comment about this? And any suggestions about what can >be done to resolve these differences? > >Thanks. >_______________________________________________ >Freesurfer mailing list >Freesurfer@nmr.mgh.harvard.edu >https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer > > >The information in this e-mail is intended only for the person to whom it >is >addressed. If you believe this e-mail was sent to you in error and the >e-mail >contains patient information, please contact the Partners Compliance >HelpLine at >http://www.partners.org/complianceline . If the e-mail was sent to you in >error >but does not contain patient information, please contact the sender and >properly >dispose of the e-mail. > ________________________________ 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. _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
