Can the Relayed Nuclear Overhauser Enhancement Effect at -1.6 ppm Provide Unique Contrast in an Ischemic Stroke Model?

Motivation: NOE(-1.6 ppm) may provide vital information about a different stage of the ischemic cascade, allowing for a more in-depth analysis of ischemic injury. Goal(s): To investigate whether NOE(-1.6 ppm) can uncover new insights into ischemic injury. Approach: CEST data in an ischemic stroke model were acquired to compare the information provided by NOE(-1.6 ppm) with that obtained from PWI, DWI, and APT. Results: NOE(-1.6 ppm) was observed to be lower in the ischemic region, with the deficit areas being equal to or larger than the ADC deficit areas but smaller than the AREX(3.5 ppm) deficit areas. Impact: NOE(-1.6 ppm) offers unique contrast compared to PWI, DWI, and APT imaging in ischemic tissues. Altogether, the mismatches reveal four zones of increasing sizes within the ischemic tissue, potentially reflecting different pathophysiological information.