Protocols - This page is still under development
T1 weighted protocols typically work well with the phantom and software. T2 weighted protocols do not work well. A scan should fully cover the phantom and slice thickness should be no greater than 1.5mm. A library of protocols, their usability, and recommendations is under development. Users are free to experiment with different protocols.
Scout scan – can be almost anything, as long as it is in axial orientation.
We use: 2D Fast Gradient Echo, TE = 3.5 ms, TR=100 ms, Flip angle 30 degrees, Bandwidth 15.63 kHz, FOV 24 cm, Slice thickness 3.0 mm, Frequency direction A/P, matrix 128x128, NEX 1, Phase FOV 1, 1 slice at isocenter.
QC Scan example:
2D Fast Gradient Echo. Sagittal Slice.
TE/TR/Flip = 4.5/100/60. Bandwidth 31.25 kHz. Frequency Direction S/I. Matrix 256x256, NEX 1, Phase FOV 1, FOV = 24 cm, slice thickness 1.5 mm, spacing interleaved.
Tried-and-true ADNI protocols for various scanner/coil setups can be found here:
adni.loni.ucla.edu/methods/documents/mri-protocols/
The ADNI protocols linked to above are patient protocols. For successful phantom scanning the slice thickness must be reduced to 1.5 mm or less.
Another example:
Scanner: 1.5 T GE Twinspeed (using zoom coil)
Sequence: 3D SPGR T1w
TR: 21 ms
TE: 8 ms
Flip Angle: 30°
Bandwidth 15.63 kHz
FOV 24 cm
Slice thickness 1.5 mm
Slice spacing 0 mm
number of volumes 1
number of slices in the volume 150
Matrix 256x256
NEX 1
Phase FOV 100% (24 cm – no phase wrap techniques!)
Frequency direction A/P
This gives us a total scan time of 13:51 min:sec
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