STUDY DESIGN
A prospective study evaluating a cohort of patients with spondylotic cervical spine compression.
OBJECTIVE
To analyze the potential of diffusion tensor imaging (DTI) of the cervical spinal cord in the detection of changes associated with spondylotic myelopathy, with particular reference to clinical and electrophysiological findings.
SUMMARY OF BACKGROUND DATA
Conventional magnetic resonance imaging (MRI) may provide confusing findings because of a frequent disproportion between the degree of the spinal cord compression and clinical symptoms. The DTI is known to be more sensitive to subtle pathological changes of the spinal cord compared with conventional MRI.
METHODS
The DTI of the cervical spinal cord was performed within a group of 52 patients with spondylotic spinal cord compression and 13 healthy volunteers on a 1.5-T MRI scanner. All patients underwent clinical examination that differentiated between asymptomatic and symptomatic myelopathy subgroups, and 45 patients underwent electrophysiological examination. We measured the apparent diffusion coefficient and fractional anisotropy of the spinal cord at C2/C3 level without compression and at the maximal compression level (MCL). Sagittal spinal canal diameter, cross-sectional spinal cord area, and presence of T2 hyperintensity at the MCL were also recorded. Nonparametric statistical testing was used for comparison of controls with subgroups of patients.
RESULTS
Significant differences in both the DTI parameters measured at the MCL, between patients with compression and control group, were found, while no difference was observed at the noncompression level. Moreover, fractional anisotropy values were lower and apparent diffusion coefficient values were higher at the MCL in the symptomatic patients than in the asymptomatic patients. The DTI showed higher potential to discriminate between clinical subgroups in comparison with standard MRI parameters and electrophysiological findings.
CONCLUSION
The DTI appears to be a promising imaging modality in patients with spondylotic spinal cord compression. It reflects the presence of symptomatic myelopathy and shows considerable potential for discriminating between symptomatic and asymptomatic patients.