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arXiv · 2108.05985

Optimized multi-axis spiral projection MR fingerprinting with subspace reconstruction for rapid whole-brain high-isotropic-resolution quantitative imaging

Xiaozhi Cao·Congyu Liao·Siddharth Srinivasan Iyer·Zhixing Wang·Zihan Zhou·Erpeng Dai·Gilad Liberman·Zijing Dong·Ting Gong·Hongjian He·Jianhui Zhong·Berkin Bilgic·Kawin Setsompop
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Abstract

Purpose: To improve image quality and accelerate the acquisition of 3D MRF. Methods: Building on the multi-axis spiral-projection MRF technique, a subspace reconstruction with locally low rank (LLR) constraint and a modified spiral-projection spatiotemporal encoding scheme termed tiny-golden-angle-shuffling (TGAS) were implemented for rapid whole-brain high-resolution quantitative mapping. The LLR regularization parameter and the number of subspace bases were tuned using retrospective in-vivo data and simulated examinations, respectively. B0 inhomogeneity correction using multi-frequency interpolation was incorporated into the subspace reconstruction to further improve the image quality by mitigating blurring caused by off-resonance effect. Results: The proposed MRF acquisition and reconstruction framework can produce provide high quality 1-mm isotropic whole-brain quantitative maps in a total acquisition time of 1 minute 55 seconds, with higher-quality results than ones obtained from the previous approach in 6 minutes. The comparison of quantitative results indicates that neither the subspace reconstruction nor the TGAS trajectory induce bias for T1 and T2 mapping. High quality whole-brain MRF data were also obtained at 0.66-mm isotropic resolution in 4 minutes using the proposed technique, where the increased resolution was shown to improve visualization of subtle brain structures. Conclusion: The proposed TGAS-SPI-MRF with optimized spiral-projection trajectory and subspace reconstruction can enable high-resolution quantitative mapping with faster acquisition speed.

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Xiaozhi Cao, Congyu Liao, Siddharth Srinivasan Iyer, Zhixing Wang, Zihan Zhou, Erpeng Dai, Gilad Liberman, Zijing Dong, Ting Gong, Hongjian He, Jianhui Zhong, Berkin Bilgic, Kawin Setsompop. 2021-08-12. Optimized multi-axis spiral projection MR fingerprinting with subspace reconstruction for rapid whole-brain high-isotropic-resolution quantitative imaging. https://doi.org/10.1002/mrm.29194

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