Accelerating T1ρ Dispersion Imaging with Multiple Relaxation Signal Compensation

Abstract

Magnetic resonance imaging (MRI) can quantify characteristic values of tissues, serving as an important tool for scientific and clinical research. Magnetic resonance T1ρ relaxation time reflects the low-frequency motional processes between water and macromolecules. At high fields of 3 T and above, T1ρ is greatly affected by the chemical exchange between water and exchangeable protons, and T1ρ dispersion measured with varying spin-lock fields can be utilized to analyze and quantify the proton exchange process. However, it is time-consuming to obtain T1ρ-weighted images with different spin-lock fields, which limits its application. To solve this problem, a fast T1ρ dispersion imaging method based on multiple relaxation signal compensation strategy is proposed in this work, which compensates the T1ρ-weighted images at different locking frequencies to the same signal strength level, and combines the low-rank plus sparse model in the reconstruction. Experimental results show that the proposed method achieves good reconstruction results even when the acceleration factor is up to 7.

Keywords

• magnetic resonance quantitative imaging
• t1ρ dispersion
• signal compensation
• low-rank plus sparse