Preliminary study on cervical spinal cord in patients with amyotrophic lateral sclerosis using MR diffusion tensor imaging.

RATIONALE AND OBJECTIVES

To investigate the conventional magnetic resonance (MR) findings of cervical spinal cord, to explore the possible changes on diffusion tensor imaging (DTI) in patients with amyotrophic lateral sclerosis (ALS), and to assess the correlations between the changes on DTI and clinical parameters in patients with ALS.

MATERIALS AND METHODS

Conventional MR imaging (MRI) and DTI in 24 patients with ALS and 16 age-matched control subjects were obtained. On axial planes, regions of interest (ROIs) were marked in bilateral spinothalamic tracts (STs), posterior funiculus, and bilateral lateral corticospinal tracts (LCTs), respectively, at the levels of cervical 2-4 vertebral bodies. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of these ROIs were estimated. Independent sample t test and Pearson correlation analysis were used.

RESULTS

In patients with ALS, no abnormal findings were noted in the cervical spinal cord on conventional MRI. FA values of bilateral LCTs decreased significantly compared to those of the control group (P < .05), and ADC values of bilateral LCTs were significantly greater than those of the control group (P < .05). FA and ADC values of bilateral LCTs showed no significant difference between patients with definite and probable ALS (P > .05). No significant correlation existed between abnormal DTI parameters (FA and ADC values of bilateral LCTs) and clinical parameters (P > .05).

CONCLUSIONS

Subtle abnormalities in bilateral LCTs in the "normal-appearing" cervical spinal cord can be detected using quantitative DTI technique in patients with ALS.