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. 2024 Sep:111:57-66.
doi: 10.1016/j.mri.2024.04.003. Epub 2024 Apr 8.

2D CAIPI accelerated 3D multi-slab diffusion weighted EPI combined with qModeL reconstruction for fast high resolution microstructure imaging

Chu-Yu Lee  1 , Merry Mani  2
Affiliations

2D CAIPI accelerated 3D multi-slab diffusion weighted EPI combined with qModeL reconstruction for fast high resolution microstructure imaging

Chu-Yu Lee et al. Magn Reson Imaging. 2024 Sep.

Abstract

Purpose: To develop acceleration strategies for 3D multi-slab diffusion weighted imaging (3D ms-DWI) for enabling applications that require simultaneously high spatial (1 mm isotropic) and angular (> 30 directions) resolutions.

Methods: 3D ms-DWI offers high SNR-efficiency, with the ability to achieve high isotropic spatial resolution, yet suffers from long scan-times for studies requiring high angular resolutions. We develop 6D k-q space acceleration strategies to reduce the scan-time. Specifically, we develop non-uniform 3D ky-kz under-sampling employing a shot-selective 2D CAIPI sampling approach. To achieve inter-shot phase-compensation, 2D navigators were employed that utilize the same CAIPI trajectory. An iterative model-based 3D multi-shot reconstruction was designed by incorporating phase into the forward encoding process. Additionally, the shot-selective non-uniform ky-kz CAIPI acceleration was randomized along the q-dimension. The 3D model-based multi-shot reconstruction is then extended to a joint reconstruction that simultaneously reconstructs all the q-space points, with the help of a spatial total variation and deep-learned q-space regularization.

Results: The proposed reconstruction is shown to achieve adequate phase-compensation in both 2D CAIPI accelerated and additional ky-kz under-sampled cases. Using retrospective under-sampling experiments, we show that k-q accelerations close a factor of 12 can be achieved with a reconstruction error < 3% for both single and multi-shell data. This translates to a scan-time reduction by 3-fold for experiments with simultaneously high spatial and angular resolutions.

Conclusion: The proposed method facilitates the utilization of 3D ms-DWI for simultaneously high k-q resolution applications with close to 3× reduced scan-time.

Keywords: 3D DWI; CAIPI; K-q acceleration; Kurtosis; Multi-slab; Over-sampling; qModeL.

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References

    1. Poser BA, Koopmans PJ, Witzel T, Wald LL, and Barth M. Three dimensional echo-planar imaging at 7 Tesla. NeuroImage, 51(1): 261–266, 2010. - PMC - PubMed
    1. Engström M and Skare S. Diffusion-weighted 3D multislab echo planar imaging for high signal-to-noise ratio efficiency and isotropic image resolution. Magnetic Resonance in Medicine, 70(6): 1507–1514, 2013. - PubMed
    1. Frost R, Miller KL, Tijssen RHN, Porter DA, and Jezzard P. 3D multi-slab diffusion-weighted readout-segmented EPI with real-time cardiac-reordered k-space acquisition. Magnetic Resonance in Medicine, 72(6), 2014. - PubMed
    1. Chang HC, Sundman M, Petit L, Guhaniyogi S, Chu ML, Petty C, Song AW, and kuei Chen N. Human brain diffusion tensor imaging at submillimeter isotropic resolution on a 3Tesla clinical MRI scanner. NeuroImage, 118, 2015. - PMC - PubMed
    1. Wu W, Poser BA, Douaud G, Frost R, In MH, Speck O, Koopmans PJ, and Miller KL. High-resolution diffusion MRI at 7T using a three-dimensional multi-slab acquisition. NeuroImage, 143:1–14, 2016. - PMC - PubMed

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