Data:DBP2:Harvard
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Harvard Data
Data Access
To download this data, click on the following links:
- Ensure you are logged into the portal portal
- Download Structural MRI
- Download DTI data
- The header for each DWI file is obsolete and incorrect, download Harvard_VA_nhdr.tgz and overwrite the DWI nrrd headers
Data Description
- 1. Structural MRI (sMRI).* *For the Structural MRI volume measurements, images will be acquired using a 3T GE) at BWH in Boston, MA. We will use an 8 Channel coil in order to perform parallel imaging using ASSET (Array Spatial Sensitivity Encoding techniques, GE) with a SENSE-factor (speed-up) of 2. The structural MRI acquisition protocol will include two MRI pulse sequences. The first results in contiguous spoiled gradient-recalled acquisition (fastSPGR) with the following parameters; TR=7.4ms, TE=3ms, TI=600, 10 degree flip angle, 25.6cm^2 field of view, matrix=256x256. The voxel dimensions are 1x1x1 mm. The second- XETA (eXtended Echo Train Acquisition) produces a series of contiguous T2-weighted images (TR=2500ms, TE=80ms, 25.6 cm^2 field of view, 1 mm slice thickness). Voxel dimensions are 1x1x1 mm.
- 2. Diffusion Tensor Imaging (DTI). DTI scans will be acquired on a 3 Tesla GE system using an echo planar imaging (EPI) DTI Tensor sequence. We will use a double echo option to reduce eddy-current related distortions (Heid 2000; Alexander 1997). To reduce impact of EPI spatial distortion, we will use an 8 Channel coil that will allow us to perform parallel imaging using ASSET (Array Spatial Sensitivity Encoding Techniques, GE) with a SENSE-factor (speed-up) of 2. We will acquire 51 directions with b=*9*00, 8 baseline scans with b=0. The following scan parameters will be used: TR 17000 ms, TE 78 ms, FOV 24 cm, 144x144 encoding steps, 1.7 mm slice thickness. We will acquire *85* axial slices parallel to the AC-PC line covering the whole brain. In addition, Bo field inhomogeneity maps will be collected.
- 3. We will add one more EPI BOLD sequence at the end of the structural protocol (as it requires Brain Wave software, available only with 8 Channel coil), which will be an integral part of the functional data acquisition and analysis protocol. This sequence -- the resting state fMRI -- will be 10 minutes long, and will contain 200 repetitions of a high resolution EPI scan (96x96 in plane, 3mm thickness, TR-3000 ms, TE=30, 39 slices, ASSETT). Subjects will be asked to close their eyes, and rest, while the magnet is running.
Data Contact
If you have any questions about the data, please contact Sylvain Bouix (sylvain@bwh.harvard.edu) or Doug Terry (dougt@bwh.harvard.edu) at Harvard.