Quoting KL Chen <[log in to unmask]>:
> Dear experts,
> we just start to use a new Siemens avanto machine to study DTI. However,
> we can not find out the 6 diffusion gradient orientaiton sequence. Did
> anyone know how to check the diffusion gardient orientation sequence from
> dicom image ? or how can we know the sequence ?
At least for those SIEMENS scanners I know, the relevant information is stored
in the SIEMENS private part of the DICOM header. spm_dicom_headers reads this
into hdr{j}.CSAImageInfo, from where you can retrieve it using the
get_numaris4_val subfunction in spm_dicom_convert. Be aware that gradient
direction is given in scanner coordinates. If you want to use my dti toolbox
for analysis, you have to transform this information into analyze coordinates,
which means flipping the Y component of the direction vector.
Hope this helps,
Volkmar
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