Kung, H-T., Cui, S., Kaplan, J.T., Joshi, A., Leahy, R.M., Nayak, K.S., & Haldar, J.P. (2024). Diffusion tensor brain imaging at 0.55T: A feasibility study. Magnetic Resonance in Medicine,92(4). doi: 10.1002/mrm.30156
Purpose: To investigate thef easibility of diffusion tensor brain imaging at 0.55T
with comparisons against 3T.
Methods: Diffusion tensor imaging data with 2 mm isotropic resolution was
acquiredonacohortoffivehealthysubjectsusingboth0.55Tand3Tscanners.
The signal-to-noiseratio(SNR)of the 0.55T data was improved using a previous
SNR-enhancing joint reconstruction method that jointly reconstructs the entire
set of diffusion weighted images from k-space using shared-edge constraints.
Quantitative diffusion tensor parameters were estimated and compared across
field strengths. We also performed a test–retest assessment of repeatability at
each field strength.
Results: After applying SNR-enhancing joint reconstruction, the diffusion
tensor parameters obtained from 0.55T data were strongly correlated (R2 ≥
0.70) with those obtained from 3T data. Test–retest analysis showed that
SNR-enhancing reconstruction improved the repeatability of the 0.55T diffusion
tensor parameters.
Conclusion: High-resolution in vivo diffusion MRI of the human brain is
feasible at 0.55T when appropriate noise-mitigation strategies are applied.