A Follow-up Study of Postoperative DCM Patients Using Diffusion MRI with DTI and NODDI

Area of Science:

• Neuroimaging
• Spinal Cord Imaging
• Advanced Diffusion MRI

Background:

• Degenerative cervical myelopathy (DCM) is a condition affecting spinal cord function.
• Diffusion tensor imaging (DTI) is used for DCM diagnosis but has limitations in specificity for microstructural assessment.
• Advanced diffusion models like neurite orientation dispersion and density imaging (NODDI) offer improved microstructural insights.

Purpose of the Study:

• To investigate the relationship between spinal cord microstructures and dysfunction in DCM patients.
• To evaluate the utility of DTI and NODDI in assessing spinal cord integrity and function post-surgery.
• To correlate advanced imaging metrics with clinical outcomes in DCM.

Main Methods:

• A retrospective cohort study involving 58 postoperative DCM patients and 14 healthy controls.
• Diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) metrics were acquired at the most stenotic levels.
• Statistical analyses included t-tests for group comparisons and Spearman correlation with modified Japanese Orthopedic Association (mJOA) scores.

Main Results:

• Significant differences in DTI metrics, neurite density (Vic), and free water fraction (Viso) were observed between DCM patients and controls.
• DTI metrics (FA, RD, MD) and NODDI metric (Vic) showed significant correlations with mJOA scores.
• Neurite density (Vic) was positively correlated with mJOA, suggesting its importance in functional recovery.

Conclusions:

• DTI and NODDI are valuable tools for evaluating spinal cord function in DCM patients.
• NODDI results suggest that decreased neurite density, rather than increased orientation dispersion, may underlie FA reduction in DCM.
• Advanced diffusion imaging aids in understanding microstructural changes and their correlation with clinical status in DCM.