Diffusion Tensor Imaging as a novel technique in early detection of cervical spondylotic myelopathy

Abstract

Introduction: Diffusion tensor imaging (DTI) is an advanced MR imaging technique which helps in early detection of cervical spondylotic myelopathy (CSM). Decompressive surgery performed during early stages of the disease was reported to be more successful when compared with later stages. Aim: To evaluate the usefulness of diffusion tensor imaging (DTI) in early stages of cervical spondylotic myelopathy (CSM) and to aid in better surgical outcome. Materials and methods: This prospective observational study included 25 patients with clinical diagnosis of cervical spondylotic myelopathy who underwent routine MRI of the cervical spine. Conventional MRI sequences along with diffusion tensor imaging (DTI) were performed. Quantitative fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were compared at stenotic and nonstenotic segments. Results: A statistically significant difference in mean FA and ADC values were seen at stenotic and nonstenotic segments. In the most stenotic segments, the mean FA value was 0.415 ± 0.203 and in the nonstenotic segment, the mean FA value was 0.717 ± 0.160, which was statistically significant (P < 0.001). The mean ADC value in the most stenotic segments was 1.777 ± 1.005 x 10^-3 mm²/s and that of the nonstenotic segments was 1.010 ± 0.458 x 10^-3 mm²/s. The difference in the mean ADC value was statistically significant (p <0.001). Conclusion: Use of diffusion tensor imaging (DTI) along with conventional MRI sequences enables early detection of the disease and helps in appropriate timing of surgery.

Keywords: Diffusion tensor imaging (DTI), cervical spondylotic myelopathy (CSM), apparent diffusion coefficient (ADC), fractional anisotropy (FA).