Speeding Up CEST

MRI scan
  MRI scan
Top: Standard CEST
Bottom: Keyhole CEST, factor 2 acceleration

Standard CEST imaging requires a long scan time, especially when acquiring high-resolution Z-spectra per imaging voxel.

Our lab is investigating several ways to make CEST faster:

One approach is to undersample using a keyhole approach: acquiring a high-resolution reference image and low resolution Z-spectra. We combine CEST with other undersampling schemes and sparse sampling approaches.

Another approach is to give up some spatial information. In many applications (e.g. lesion characterization) only localized information is desired. Recently, we have combined ultrafast Z-spectroscopy with volume localization using point resolved spectroscopy (PRESS) to create a method capable of quick Z-spectrum acquisition at a specific locale. This method —ultrafast localized CEST-spectroscopy with PRESS (UCEPR) — can obtain the entire Z-spectrum of a voxel using only two scans, significantly accelerating CEST.