Quantitative Assessment of Spinal Cord Injury in Cervical Spondylotic Myelopathy: A Comparison Study of MAGiC and MUSE-DTI.

OBJECTIVES

To compare synthetic magnetic resonance imaging (MAGnetic resonance image Compilation, MAGiC) and MUSE-DTI (MUltiplexed Sensitivity Encoding-Diffusion Tensor Imaging) in determining the severity of spinal cord injury in cervical spondylotic myelopathy (CSM).

METHODS

All subjects (69 CSM subjects and 15 controls) underwent synthetic MRI and MUSE-DTI scans. Japanese Orthopaedic Association (JOA) score was evaluated preoperatively. Cervical canal stenosis degree was graded 0-Ⅲ using an MRI grading system. Twelve patients received surgical intervention and JOA evaluation 1 year after operation. Regions of interest covered the whole spinal cord at the maximal compression level (MCL) and C2 vertebral level to generate T1, T2 and PD values from synthetic quantitative map and fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) values from MUSE-DTI map.

RESULTS

ADMCL values demonstrated higher sensitivity to spinal microstructural changes than other parameters, increasing from Grade Ⅰ-Ⅲ and decreasing at Grade Ⅰ compared to Grade 0 (P < 0.05). FAMCL and T1MCL values decreased from Grade 0-Ⅱ. Furthermore, ADC2 values in Grade I were significantly lower than Grade 0 (P = 0.005). FAC2 values correlated with the minimum FA values of multi-segment compressed spinal cord (P = 0.007). All MUSE-DTI parameters at MCL correlated with JOA scores across all grades. The preoperative ADMCL values correlated with postoperative recovery rate, whereas MAGiC-derived parameters did not.

CONCLUSION

MUSE-DTI parameters better reflected microstructural alterations and secondary damages of spinal cord and correlated with the JOA scores and postoperative recovery rate. Therefore, MUSE-DTI could provide more quantitative information to evaluate the severity of spinal cord injury in CSM.