Contents
CBU default imaging sequences
Introductory note
The sequences shown on this page are meant to be used as guidelines, but they can be modified in order to meet the needs of your study. If you would like some advice on setting up your sequence, please contact Marta Correia ( marta.correia@mrc-cbu.cam.ac.uk ).
If you want to double check what parameters were used for images already acquired, you can also look at the information from the DICOM headers, which SPM saves when converting to Nifti format. After DICOM conversion every folder has a dicom_headers.mat file. In Matlab:
>> load dicom_headers.mat >> DICOMHEADERS{1}will let you check the parameters for the images you've acquired.
CBU_EPI
For fMRI
Description |
Standard EPI sequence for fMRI |
Acquisition time |
2 s (per volume) |
Type |
2D |
Slices |
32 |
Slice gap |
25% |
Slice thickness |
3 mm |
Slice order |
Descending (32,31,...,1) |
FOV |
192 mm x 192 mm |
Matrix |
64 x 64 |
Resolution |
3 mm x 3mm |
TR |
2000 ms |
TE |
30 ms |
Flip angle |
78 deg |
Bandwidth |
2232 Hz/Px |
Echo spacing |
0.51 ms |
Trigger pulse timing
To within a few ms, the stimulus delivery trigger pulse happens 35 ms before the acquisition of the first scan (centre of k space) of each volume. Note there is a latency of 20 ms in the visual display. The trigger pulse length is 1 ms.
CBU_MEPI
The multi-echo sequence was developed by Benedikt Poser and colleagues at the FC Donders Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands. A comparison between multi-echo and standard fMRI acquisition can be found here http://onlinelibrary.wiley.com/doi/10.1002/mrm.20900/pdf .
Description |
Echo planar imaging at multiple echo times |
Acquisition time |
2.47s (per volume) |
Type |
2D |
Slice |
32 |
Slice gap |
25% |
Slice thickness |
3mm |
Slice order |
Descending (32,31,...,1) |
FOV |
192mm x 192mm |
Matrix |
64 x 64 |
Resolution |
3mm x 3mm |
TR |
2470ms |
TE |
9.4ms, 21.2ms, 33ms, 45ms, 57ms |
Flip angle |
83 deg |
Parallel imaging |
GRAPPA |
CBU_MultiBand_EPI
A wide range of different multi-band factors, voxel resolutions and repetition times can be achieved for both fMRI and diffusion MRI. Please contact Marta Correia marta.correia@mrc-cbu.cam.ac.uk to discuss the parameters which will best suit your needs. If you would like to know the exact imaging parameters used for your study, please contact the radiographers ( radiographers@mrc-cbu.cam.ac.uk ).
CBU_MPRAGE
Description |
High-resolution structural MRI |
Acquisition time |
4 min 32s |
Type |
3D |
FOV |
256 mm x 240 mm x 192mm |
Matrix |
256 x 240 x192 |
Resolution |
1 mm isotropic |
TR |
2250 ms |
TI |
900 ms |
TE |
2.99 ms |
Flip angle |
9 deg |
Parallel imaging |
GRAPPA |
CBU_T2
Description |
High-resolution T2-weighted structural MRI |
Acquisition time |
4 min 30s |
Type |
3D |
FOV |
256 mm x 240 mm x 192mm |
Matrix |
256 x 240 x192 |
Resolution |
1 mm isotropic |
TR |
2800 ms |
TE |
408 ms |
Flip angle |
90 deg |
Bandwidth |
751 Hz/Px |
Echo spacing |
3.36 ms |
Parallel imaging |
GRAPPA |
CBU_TSE
Description |
T2-weighted structural MRI |
Acquisition time |
1 min 38 s |
Slices |
29 |
Slice gap |
30% |
Slice thickness |
4 mm |
Type |
2D |
FOV |
220 mm x 220 mm |
Matrix |
320 x 320 |
Resolution |
0.7 x 0.7 mm |
TR |
5060 ms |
TE |
102 ms |
Flip angle (refoc. pulse) |
140 deg |
Parallel imaging |
GRAPPA |
CBU_Fieldmapping
Description |
Magnetic field mapping sequence. Required for |
Acquisition time |
54 s |
Type |
2D |
Slices |
32 |
Slice gap |
25% |
Slice thickness |
3 mm |
FOV |
192 mm x 192 mm |
Matrix |
64 x 64 |
Resolution |
3 mm x 3 mm |
TR |
400 ms |
TE |
5.19 ms / 7.65 ms |
Flip angle |
60 deg |
CBU_DTI_64InLea_2x2x2_32chn
Description |
Standard sequence for diffusion MRI. |
Acquisition time |
10min 14sec |
Type |
2D |
Slices |
68 |
Slice gap |
none |
Slice thickness |
2 mm |
Slice order |
Interleaved |
FOV |
192 mm x 192 mm |
Matrix |
96 x 96 |
Resolution |
2 mm x 2 mm |
TR |
8500 ms |
TE |
90 ms |
Diff directions |
64 |
Diff weightings |
2 |
b-value1 |
0 s/mm2 |
b-value2 |
1000 s/mm2 |
Parallel imaging |
GRAPPA |
For more information on the diffusion MRI sequence go to AnalyzingDiffusion. If you have an ongoing study or wish to compare your results with data that you had previously acquired, the old standard CBU sequence for diffusion imaging (CBU_DTI_64D_1A) will still be available to be used.
CBU_SWI
Description |
Susceptibility Weighted Imaging to image vessels and veins in the brain |
Acquisition time |
6min 38s |
Type |
3D |
Slices |
72 |
Slice gap |
0% |
Slice thickness |
1.2 mm |
Slice order |
Interleaved |
FOV |
230mm x 178mm |
Matrix |
448 x 381 |
Resolution |
0.6 mm x 0.5 mm |
TR |
28 ms |
TE |
20 ms |
Flip angle |
15 deg |
Bandwidth |
120 Hz/Px |
Other imaging sequences
Many other imaging sequences are available, so if you can't find what you need in the list above please contact Marta Correia ( marta.correia@mrc-cbu.cam.ac.uk ).