3T Multiband: Difference between revisions
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* Offc/Ang: free rotatable Yes | * Offc/Ang: free rotatable Yes | ||
* PNS moderate | * PNS moderate | ||
* Flip angle --> Ernst angle | * Flip angle --> [http://www.mritoolbox.com/ErnstAngle.html Ernst angle] | ||
* Planning: stevig anguleren. Read-out richting omdraaien AP-->PA? | * Planning: stevig anguleren. Read-out richting omdraaien AP-->PA? | ||
Revision as of 10:27, 15 December 2017
Multiband
Sequence-parameters
- Shimming
- Shimbox: inside brain? Is bottomline shimbox wrt OFC / air transition most important?
- What is a good shim?LINEWIDTH checken voor scannen? Log values
- Acquire extra B0-scan as check to avoid large B0-gradient?
- Use Maarten's patch for image based shimming: this patch applies shim to B0-prescan
- TR:
- for physiological noise correction, aim for 750ms
- minimal TR: to be adjusted on-scanner (not realistic in VM)
- Gradient mode: Set to Enhanced if duty cycle is limiting factor (enormous difference on AMC-wide bore scanner)
- Water Fat Shift: minimal. Increase to reduce TR
- TE hoeft niet in phase: niet belangrijk voor vet want signaal is al dispersed met deze TE. TE~32.23, 27 is te kort.
- Geen slice gap (maar waarom?)
- Acquired/Reconstructed Matrix size should match
- Multiband factor * SENSE ~= 6
- Half scan: no. Unless minimal TR deviates more than 10% from shortest. But: see Gradient mode
- Dynamic Stabilization: regular (niet enhanced, kost teveel tijd)
- Offc/Ang: free rotatable Yes
- PNS moderate
- Flip angle --> Ernst angle
- Planning: stevig anguleren. Read-out richting omdraaien AP-->PA?
Data-export
- enhanced dicom does not work for >16k images
- export nifti
- export PAR/REC or XML/REC to store sequence parameters