Diffusion tensor imaging of the cervical spinal cord of patients with relapsing-remising multiple sclerosis: a study of 41 cases.

OBJECTIVE To evaluate the fractional anisotropy (FA) values of the multiple sclerosis (MS) plaques and normal-appearing cervical spinal cord (NASC) by diffusion tensor MRI imaging (DTI). METHOD Forty-one patients with relapsing-remising MS and 37 controls were evaluated. All MRI exams were performed using a conventional protocol, as well as diffusion tensor MR imaging. Regions of interest were placed within the spinal cord lesions and in the normal appearing spinal cord adjacent to the plaque. RESULTS The FA values were statistically reduced in the plaques compared to the surrounding NASC and to equivalent location in controls. A reduction in FA values was also observed in the spinal cord of MS patients without visible lesions on T2WI. CONCLUSION We observed reduced fractional anisotropy in the demyelinating plaques and in the NASC of MS patients, corroborating the hypothesis that the histological extension of the MS lesions is more severe than the abnormalities seen in the conventional MRI sequences.