Diffusion-weighted 3D multislab echo planar imaging for high signal-to-noise ratio efficiency and isotropic image...

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Diffusion-Weighted Imaging (DWI)

Background:

• High-resolution, high signal-to-noise ratio (SNR) diffusion-weighted MRI data is crucial for detailed brain studies.
• Existing methods like 2D diffusion-weighted single-shot echo planar imaging (DW 2D ss-EPI) have limitations in resolution and SNR efficiency for full brain coverage.

Purpose of the Study:

• To develop and evaluate an isotropic, high-resolution, SNR-efficient 3D encoded diffusion-weighted MRI sequence.
• To achieve full brain coverage with improved data quality for diffusion studies.

Main Methods:

• Utilized a generalized autocalibrating partially parallel acquisitions (GRAPPA) accelerated diffusion-weighted 3D multislab echo planar imaging (EPI) sequence.
• Integrated multiple Fourier encoded slabs into a full volume reconstruction.
• Incorporated 2D phase navigation and in-plane motion correction for data integrity.

Main Results:

• Demonstrated reconstructed data with 1.5-mm³ nominal resolution, assessed under motion and varying slab thicknesses.
• Compared SNR efficiency between the novel 3D multislab EPI and DW 2D ss-EPI, showing significant improvements.
• Presented a 1.3-mm³ full brain scan with 45 diffusion directions.

Conclusions:

• Diffusion-weighted 3D multislab EPI is a viable alternative for high-resolution, high-SNR diffusion MRI studies requiring full brain coverage.
• The presented sequence offers significantly higher SNR efficiency compared to the established 2D diffusion-weighted single-shot echo planar imaging (DW 2D ss-EPI).
• This advancement facilitates more comprehensive and accurate diffusion analysis in neuroimaging.