Abstract:
PURPOSE:To use the variable delay multipulse (VDMP) chemical exchange saturation transfer (CEST) approach to obtain clean amide proton transfer (APT) and relayed Nuclear Overhauser enhancement (rNOE) CEST images in the human brain by suppressing the conventional magnetization transfer contrast (MTC) and reducing the direct water saturation contribution. METHODS:The VDMP CEST scheme consists of a train of RF pulses with a specific mixing time. The CEST signal with respect to the mixing time shows distinguishable characteristics for protons with different exchange rates. Exchange rate filtered CEST images are generated by subtracting images acquired at two mixing times at which the MTC signals are equal, while the APT and rNOE-CEST signals differ. Because the subtraction is performed at the same frequency offset for each voxel and the CEST signals are broad, no B0 correction is needed. RESULTS:MTC-suppressed APT and rNOE-CEST images of human brain were obtained using the VDMP method. The APT-CEST data show hyperintensity in gray matter versus white matter, whereas the rNOE-CEST images show negligible contrast between gray and white matter. CONCLUSION:The VDMP approach provides a simple and rapid way of recording MTC-suppressed APT-CEST and rNOE-CEST images without the need for B0 field correction.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Xu X,Yadav NN,Zeng H,Jones CK,Zhou J,van Zijl PC,Xu Jdoi
10.1002/mrm.25990subject
Has Abstractpub_date
2016-01-01 00:00:00pages
88-96issue
1eissn
0740-3194issn
1522-2594journal_volume
75pub_type
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