PET-MR compatible CEST method for imaging of Alzheimer’s Disease.

Motivation: Current methods of assessing Alzheimer's disease, such as PET scans, are expensive, involve exposure to radiation and have limited resolution. Goal(s): We aim to demonstrate the applicability a novel CEST MRI method to measure the relayed Nuclear Overhauser effect, which may be sensitive to amyloid-β aggregates. Approach: We have developed and tested a radially sampled CEST sequence (ssGraspCEST) that can be acquired on hybrid PET-MRI systems. Results: MCI and AD patients appeared to have narrower distributions of LDNOE and ∆ST(-3.6) and higher values. However, due to the limited sample size at this time, no significant differences were observed between the two groups. Impact: We demonstrated the implementation of a fast, motion-robust CEST method, fully compatible with hybrid PET-MRI systems and particularly suitable for imaging elderly participants who cannot hold still during the scan, which may be useful in future for detecting pathological aggregates.