Slice timing for multiband accelerated EPI data

Submitted by Authenty on

Dear Prof.Yan

 

I have some questions in slice timing by using dparbi to preprocess the multiband accelerated EPI data. According to instruction of slice order during slice timing in SPM12, I got the slice times of each session by running in Matlab the following codes

hdr=spm_dicom_headers('dicom.ima');

slice_times=hdr{1}.Private_0019_1029;

 

Then, I followed the instruction present in 'http://wiki.rfmri.org/sites/default/files/Wiki/DPABI/DPARSF/SliceTiming/SliceOrderInfo.tsv' to have slice times of each session and each subject well organized. 

 

But it remains unknown how to set the Reference slice.  The instruction of slice order during slice timing in SPM12 says 

 

“ if doing so (entering the slice timing in ms for each slice individually) , the next item(reference slice) will contain a reference time(in ms) instead of the slice index of the reference slice” 

 

 

My questions are

1. Given TR=2000ms and slice number in each TR=75, what should I input in the Reference Slice cell of DPARSFA? 

2. By the way, slice number should be 75, and slice order should be set to 0 while saving the SliceOrderInfo.tsv under the working directory, is that all right ?

 

Thanks a lot for your great help and you have done really wonderful work!

 

Xilei Zhang

 

Maybe I found the answers.

The only two things I should do is to 1. set slice Number as 0, 2. save correct SliceOrderInfo.tsv under the working directory. It doesn't matter what to fill in the Slice Order and Reference Slice blanks, because the program will accordingly determine the SliceNumber and extract the slice order sequence in ms, based on which the Reference slice will be determined as SliceOrder(ceil(SliceNumber/2)) by default.

 

Is it the truth?

Xilei