To test new models, e.g. various fibre reconstruction methods, high-quality diffusion MRI data sets acquired with multiple b-values is a must. This ex vivo diffusion MRI data set consists of multiple b-values acquired within the same scanning session and, since motion during scanning is absent, the dataset allows voxel-to-voxel comparison across b-values directly on the acquired dataset.
Facts about the dataset:
Sequence: diffusion weighted pulse gradient spin echo (PGSE) with single line readout. Image matrix: 128x64, Voxel size: 0.51x0.51x0.5 mm^3, slices: 5, TR= 2500 ms, TE=67.8ms and NEX=4 (averaged off line). Diffusion weighted gradient strength (Gmax)* has been increased in steps of [29, 44, 49, 56, 68, 80, 111] mT/m, small delta: 27 ms, big delta: 33.5 ms, producing b-values of [1018, 2475, 3069, 4009, 5911, 8181,11295, 15750] s/mm^2
Dyrby TB, Baaré WF, Alexander DC, Jelsing J, Garde E, Søgaard LV, An ex vivo imaging pipeline for producing high-quality and high-resolution diffusion weighted imaging datasets, Human Brain mapping, April,2011
Download the multiple-bvalue dataset here
Observed problems or artifacts: Please note that the data set only contain 4 axial slices of a half pig brain and that there is a gab between slices. We have observed minor motion but have not aligned the data set before off line averaging (NEX4) due to this gab.
The Lundbeck Foundation and the Velux Foundation