Figure 1.

Interleaved MRS‐fMRI (A) can be performed by using dynamic linear shims. Although this would be an obvious approach up to 3T, higher order shimming is required at higher field. The MRS linewidth was improved using the higher order shims from 16 Hz linewidth using dynamic linear shimming (B) to 12 Hz linewidth with HOS‐DLT (C). At the same time, image distortions in the EPI are reduced. Compared to the gradient echo reference image (D) EPI imaging with linear shims leads to high image distortions at ultra‐high field (E). Using the third order HOS‐DLT shim (F) the EPI distortions are reduced while simultaneously enabling the use of higher order shimming for interleaved MRS