Early experiences with diffusion tensor imaging and magnetic resonance tractography in stroke patients

Parmar H, Golay X, Lee KE, Hui F, Sitoh YY
Correspondence: Dr Hemant Parmar, parurad@hotmail.com

ABSTRACT
Introduction Recent advances in magnetic resonance (MR) diffusion tensor imaging technique enable evaluation of the anisotropy of white matter tracts in-vivo, as well as the integrity of fibre tracts and their orientation. We describe our initial experiences with diffusion tensor imaging and MR tractography techniques to evaluate the structural degeneration of white matter tracts following stroke.
Methods Diffusion tensor imaging data were acquired in 11 cases with stroke on a 3T MR imaging scanner, with three-dimensional diffusion tensor imaging-based colour maps and MR tractography performed offline. We evaluated the spatial relationships of the eloquent white matter tracts to the infarcts and areas of haemorrhage, and classified therewith the tracts as either disrupted or displaced. We compared these with the clinical severity of the neurological deficits and prognosis.
Results A good correlation was found between tractography findings and patient's clinical recovery. All the patients with disruption of white matter tracts had residual deficits on clinical follow-up, whereas the patients with displaced tracts had near complete neurological recovery.
Conclusion Diffusion tensor imaging and MR tractography provide a novel and useful method to directly visualise changes in the white matter tracts in stroke. This can potentially allow clinical-imaging correlation with prognostic potential.

Keywords: cerebrovascular accident, diffusion magnetic resonance imaging, echo planar imaging, magnetic resonance imaging, magnetic resonance tractography, stroke
Singapore Med J 2006; 47(3): 198-203