2016_Imaging for Physicists
B0 mapping
Magnitude
Difference Phase (TE1) Phase (TE2)
• Air/tissue interfaces problematic • Dynamic & HO shimming • May be measured/corrected: • Image at two different TEs • Reconstruct phase difference • Bhagwandien measured -5 to +6ppm i.e. nearly twice WFS
γΔTE Δφ
ΔB
=
0
Maximum 34 Hz (0.3 ppm)
Maximum 203 Hz (1.6 ppm @ 3T)
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