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arXiv · 2510.06022

MC BTS: simultaneously resolving magnetization transfer effect and relaxation for multiple components

Albert Jang·Hyungseok Jang·Nian Wang·Alexey Samsonov·Fang Liu
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Abstract

We propose a signal acquisition and modeling framework for multi-component tissue quantification that encompasses transmit field inhomogeneity, multi-component relaxation and magnetization transfer (MT) effects. By applying off-resonance irradiation between excitation and acquisition within an RF-spoiled gradient-echo scheme, in combination with multiple echo-time acquisitions, both Bloch-Siegert shift and magnetization transfer effects are simultaneously induced while relaxation and spin exchange processes occur concurrently. Simulation results showed excellent agreement with the derived analytical signal equation across a wide range of flip angles and echo times. Monte Carlo analyses further validated that the three-pool parameter estimation pipeline performed robustly over various signal-to-noise ratio conditions. Multi-parameter fitting results from in vivo brain and knee studies yielded values consistent with previously reported literature. Collectively, these findings confirm that the proposed method can reliably characterize multi-component tissue parameters in macromolecule-rich environments while effectively compensating for $B_1^+$ inhomogeneity.

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Albert Jang, Hyungseok Jang, Nian Wang, Alexey Samsonov, Fang Liu. 2025-10-07. MC BTS: simultaneously resolving magnetization transfer effect and relaxation for multiple components. https://arxiv.org/abs/2510.06022

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