Assessment of frequency drift on CEST MRI and dynamic correction: application to gagCEST at 7 T.

ABSTRACT: PURPOSE:To investigate the effect of a frequency drift of the static magnetic field on 3D CEST MRI based on glycosaminoglycans (GAGs) of articular cartilage at 7 T and to introduce a retrospective correction method that uses the phase images of the gradient-echo readout. METHODS:Repeated gagCEST and B0 measurements were performed in a glucose model solution and in vivo in the knee joint of 3 healthy volunteers at 7 T. Phase images of the modified 3D rectangular spiral centric-reordered gradient-echo CEST sequence were used to quantify and compensate the apparent frequency drift in repeated gagCEST measurements. RESULTS:The frequency drift of the MRI scanner strongly influences the gagCEST signal in the articular cartilage of the human knee joint. The gagCEST signal in the articular cartila

SUBMITTER: Windschuh J 

PROVIDER: S-EPMC6258338 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature