2017 Imaging for Physicists Coursebook

Result: geometrical distortion in spin-echo imaging

x B

zy

G zyxB ) , ,( 

) , ,(

 

0

x x



x

1

G

G

x

x

In the frequency-encoding direction, both the non-linearity of the frequency- encoding gradient and static field inhomogeneity cause geometric distortions

B  

G

y

y y

1

G

y

In the phase-encoding direction, distortions are solely caused by the non- linearity of the phase-encoding gradient