Difference in distance measurements between encoding directions

[aelster]

Dear Xen,

The most likely cause of the problem is not your sequences, but one or more miscalibrated gradients. Gradients commonly drift over time and need to be recalibrated periodically. A service engineer will know exactly how to do this.

A less likely but possible cause is that your Bo field contains significant inhomogeneities due to improper adjustment of shims, gradient offsets, or presence of a ferromagnetic foreign object. Once again, a service engineer should be consulted who can identify and fix this problem.

ADE