Role of Diffusion Tensor Imaging in Early Detection of Cervical Spondylotic Myelopathy: An Observational Study

Introduction: Cervical Spondylotic Myelopathy (CSM) is a common degenerative spinal condition that can lead to significant neurological deficits if not detected early. Conventional Magnetic Resonance Imaging (MRI), while useful, has limited sensitivity in detecting early myelopathic changes. Diffusion Tensor Imaging (DTI), a novel MRI technique, offers quantitative parameters such as Fractional Anisotropy (FA) and Apparent Diffusion Coefficient (ADC), which may aid in the early detection and severity assessment of CSM. Aim: To estimate and compare DTI parameters (FA and ADC) at stenotic and non stenotic levels in patients with CSM and to correlate these parameters with clinical severity using the modified Japanese Orthopaedic Association (mJOA) score. Materials and Methods: An observational study was conducted at a Chettinad hospital and research institute involving 30 patients with CSM. Ethical clearance and informed consent were obtained. Patients underwent conventional MRI and DTI sequences using a 3T Philips MRI scanner. The FA and ADC values were measured at stenotic and non stenotic levels. Clinical severity was assessed using the mJOA score. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) version 27, with paired sample t-tests and Pearson’s correlation (p<0.05 considered significant). Results: The mean FA value was significantly lower at stenotic levels (0.46) compared to non stenotic levels (0.61) (p=0.001). Conversely, the mean ADC value was significantly higher at stenotic levels (1.35) compared to non stenotic levels (1.02) (p=0.001). A strong positive correlation was observed between FA values at stenotic levels and mJOA scores (r=0.946, p=0.001), while a strong negative correlation was found between ADC values and mJOA scores (r=-0.920, p=0.001). Conclusion: DTI parameters (FA and ADC) demonstrated significant changes at stenotic levels in CSM patients and correlated strongly with clinical severity. DTI holds promise as a quantitative tool for early detection and severity assessment of CSM.