| T O P I C R E V I E W |
| ken.roberts |
Posted - Feb 26 2003 : 6:38:45 PM
Hello.
Recently over at the CCN, we have been working on designing a couple of different functional imaging experiments that vary quite a bit in their requirements. I was wondering if someone could help us figure out which pulse sequences are available, and what the pros and cons of each are. Specifically, between the several spiral sequences available, and the EPI sequence, how fast can you go on each of the machines? How sensitive are they relative to one another? Which ones provide the best recovery of signal from areas prone to magnetic susceptibility artifacts? Which provide best spatial localization of activity? Generally, what do the k-space trajectories look like? Are any of them considered more "experimental" than the others? Are there any other details we should know about that I havent asked about? Is there is a general document already at the BIAC that has all of this in it already? Any information you could provide would be greatly appreciated.
Thank you.
Ken
|
| 1 L A T E S T R E P L I E S (Newest First) |
| allen.song |
Posted - Feb 27 2003 : 3:56:47 PM
Here is a short list of available functional imaging sequences (both on the 1.5T and 4T):
1. The inward spiral (aka invspiral), it has advantages such as good signal recovery at ventral brain areas and high temporal resolution (maximum speed: 24 slices/s at 1.5 T and 23 slices/s at 4 T).
2. The forward spiral (aka sss), it can be used to acquire images of extremely short TE (e.g. perfusion scans) and can accommodate diffusion weighting schemes better than the inward spiral sequence. Maximum speed: 16 slices / s.
3. EPI sequences. epiRT -- real time EPI, good for clinical scans, maximum speed (reliably) 12 slices/s. epiduke -- duke EPI, faster acquisition, maximum speed: 16 slices/s, however, no real time display. |
|
|
