Diffusion tensor imaging (DTI) can visualize the white matter tracts in vivo. The aim of this study was to assess the clinical utility of DTI in patients with diseases of the spinal cord. Fourteen subjects underwent magnetic resonance imaging of the spine at 1.5 T. Preliminary diagnosis of the patients suggested traumatic, tumorous, ischemic or inflammatory lesions of the spinal cord. In addition to T2-weighted images, DTI was performed with the gradients in 30 orthogonal directions. Maps of the apparent diffusion coefficient and of fractional anisotropy were reconstructed. Diffusion tensor imaging showed a clear displacement and deformation of the white matter tracts at the level of the pathological lesions in the spinal cord. This capability of diffusion tensor imaging to reliably display secondary alterations to the white matter tracts caused by the primary lesion has the potential to be of great utility for treatment planning and follow-up.