Role of diffusion tensor imaging (DTI) as a quantitative diagnostic tool in assessing cervical spondylotic myelopathy

Abstract

Aims and Objectives: To compare fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values obtained by DTI in stenotic and non-stenotic cervical spinal segments of patients with clinical evidence of cervical spondylotic myelopathy. Materials and Methods: A prospective study was conducted among 50 individuals over a period of 18 months. MRI of cervical spine was performed in patients referred/admitted to the institution with clinical suspicion of cervical spondylotic myelopathy. The protocol included: 2D sagittal T1WI, T2WI, STIR sequence, axial T2WI, T1WI, coronal STIR sequence and axial DTI sequences. Post-processing was done using Philips FIBRETRAK software. Results: In the study there was significant decrease in the values of FA at the levels with canal stenosis and a FA cut-off value ≤0.459 had sensitivity of 100% and specificity of 85.6% for diagnosing cervical spondylotic myelopathy. Similarly, there was a significant increase in the ADC value at the stenotic levels and the cut-off value >1.3265 x 10-3 mm2/s had a sensitivity of 100% and a specificity of 76%. Conclusions and Recommendations: DTI can thus be used as an efficient tool in early diagnosis of cervical spondylotic myelopathy in patients where there are no obvious changes in the signal intensity of the cord.