Diffusion tensor imaging can predict the function of spinal cord in cervical spondylotic myelopathy

Objective: To explore whether diffusion tensor imaging (DTI) could predict the spinal cord function in patients with cervical spondylotic myelopathy (CSM) and to compare DTI indices with conventional morphological indices in MRI. Methods: Fourteen patients with CSM were enrolled and received cervical spinal DTI scans and conventional MRI scan. The FA and ADC values of different levels were measured on the mid-sagittal plane, and the lowest FA and the highest ADC were recorded for each patient. At the compressed site, compression ratio (CR) was calculated as a ratio between the anteroposterior diameter and the transverse diameter of the spinal cord, and whether there was a high signal intensity in sagittal T2WI was also recorded. The clinical assessment of patients was obtained based on JOA scores. Results: The lowest FA and the highest ADC were 0.336±0.096 and 2.280±0.338 μm 2 /ms respectively, usually presented in pairs in the same level. Compared with the indices of C2/3, the lowest FA and the highest ADC both showed significantly abnormity. The patients were divided into three groups by JOA scores: Mild, Moderate and Severe. FA of the Mild group was significantly higher than the other two ( P <0.05). None of ADC, CR and high signal in T2WI differed among groups. Only the lowest FA was significantly correlated with JOA scores (R 2 =0.699, P <0.001). Conclusion: FA was more reliable to reveal the neural status and correlate with JOA scores in CSM, rather than ADC and conventional MRI indices. The lower FA was, the worse function the patient had.