Simultaneous Acquisition of Magnetic Resonance Elastography (MRE) and Diffusion Tensor Imaging (DTI) Optimized for...

Area of Science:

• Neuroimaging
• Biophysics
• Medical Physics

Background:

• Magnetic Resonance Elastography (MRE) and Diffusion Tensor Imaging (DTI) are crucial for assessing brain tissue properties.
• Current limitations include lengthy scan times and the need for separate acquisitions, hindering clinical adoption.
• Simultaneous acquisition could improve efficiency and data integration.

Purpose of the Study:

• To evaluate the feasibility of simultaneous DTI-MRE acquisition in the human brain.
• To compare the resulting diffusive and mechanical property maps with conventional DTI and MRE methods.
• To assess the potential for reducing scan time by half.

Main Methods:

• Optimized in vivo human brain DTI-MRE acquisition parameters on a 3T Siemens Prisma scanner.
• Acquired data from five healthy subjects using two optimized parameter sets.
• Computed mean diffusivity, fractional anisotropy, and shear stiffness maps; compared with conventional methods via Pearson's correlation.

Main Results:

• Simultaneous DTI-MRE demonstrated strong correlations with conventional DTI and MRE across all subjects.
• Mean diffusivity and fractional anisotropy maps showed excellent fidelity (global mean Pearson's r > 0.86, voxel-wise r > 0.7).
• Spatially averaged shear stiffness values were slightly lower in the simultaneous DTI-MRE approach.

Conclusions:

• Simultaneous DTI-MRE acquisition in the human brain is feasible, providing co-registered diffusive and mechanical property maps efficiently.
• This technique has the potential to significantly shorten scan times for clinical applications.
• Further refinements, like multi-frequency actuation, could enhance accuracy for neurology, neurosurgery, and brain injury assessment.