Data needed for doing a diffusion-weighted (DW) data analysis are the DW-MR images, the gradient direction information in a text file and an anatomical (T1-weighted) dataset, acquired in the same session. A few recommendations for data acquisition can be found at http://support.brainvoyager.com/diffusion-weighted-imaging/61.
In this manual, we use a DWI scan measured with 31 diffusion directions: 1 b0 and 30 diffusion weighted directions. The gradient file for this measurement can be found in appendix 1.6.1. Furthermore, in the same session an ADNI (modified MPRAGE) anatomy was acquired. Details of the measurement are given below.
| subject | healthy male 42yrs |
| scanner | 3T Siemens Allegra |
| DWI | 31dirs, b=800mm2/s, 75 slices, voxel size 2 × 2 × 2 mm |
| ADNI (T1) | 192 slices, voxel size 1 × 1 × 1 mm |
| Acquisition time | 25mins |
The sample data can be downloaded from the Brain Innovation ftp server on request, by emailing support@brainvoyager.com. Please put the data in \BVQXSampleData\DTI\Human31dir\ or equivalent folder.