1. Quantitative T1 mapping using multi-slice multi-shot inversion recovery EPI.
- Author
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Sanchez Panchuelo RM, Mougin O, Turner R, and Francis ST
- Subjects
- Adult, Brain metabolism, Female, Humans, Male, Brain diagnostic imaging, Brain Mapping methods, Echo-Planar Imaging methods, Image Processing, Computer-Assisted methods
- Abstract
An efficient multi-slice inversion-recovery EPI (MS-IR-EPI) sequence for fast, high spatial resolution, quantitative T
1 mapping is presented, using a segmented simultaneous multi-slice acquisition, combined with slice order shifting across multiple acquisitions. The segmented acquisition minimises the effective TE and readout duration compared to a single-shot EPI scheme, reducing geometric distortions to provide high quality T1 maps with a narrow point-spread function. The precision and repeatability of MS-IR-EPI T1 measurements are assessed using both T1 -calibrated and T2 -calibrated ISMRM/NIST phantom spheres at 3 and 7 T and compared with single slice IR and MP2RAGE methods. Magnetization transfer (MT) effects of the spectrally-selective fat-suppression (FS) pulses required for in vivo imaging are shown to shorten the measured in-vivo T1 values. We model the effect of these fat suppression pulses on T1 measurements and show that the model can remove their MT contribution from the measured T1 , thus providing accurate T1 quantification. High spatial resolution T1 maps of the human brain generated with MS-IR-EPI at 7 T are compared with those generated with the widely implemented MP2RAGE sequence. Our MS-IR-EPI sequence provides high SNR per unit time and sharper T1 maps than MP2RAGE, demonstrating the potential for ultra-high resolution T1 mapping and the improved discrimination of functionally relevant cortical areas in the human brain., Competing Interests: Declaration of Competing Interest None., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2021
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