Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2004 Feb;127(Pt 2):340-50.
doi: 10.1093/brain/awh041. Epub 2003 Nov 7.

Diffusion tensor MRI of early upper motor neuron involvement in amyotrophic lateral sclerosis

Miriam Sach  1 , Gerhard Winkler, Volkmar Glauche, Joachim Liepert, Bernhard Heimbach, Martin A Koch, Christian Büchel, Cornelius Weiller
Affiliations

Diffusion tensor MRI of early upper motor neuron involvement in amyotrophic lateral sclerosis

Miriam Sach et al. Brain. 2004 Feb.

Abstract

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative system disorder affecting both upper and lower motor neurons. Despite supportive electrophysiological investigations, the involvement of the upper motor neuron is often difficult to assess at an early stage of disease. Diffusion tensor MRI provides an estimate of the orientation of fibre bundles in white matter on the basis of the diffusion characteristics of water. Diffusivity is generally higher in directions along fibre tracts than perpendicular to them. This degree of directionality of diffusion can be measured as fractional anisotropy. Changes in tissue structure due to degeneration of the corticospinal fibres can lead to a modification of the degree of directionality which can be detected by diffusion tensor MRI. We investigated 15 patients with ALS, six of whom had no clinical signs of upper motor neuron involvement at the time of MRI investigation, but developed pyramidal tract symptoms later in the course of their disease. These patients met the El Escorial criteria as their disease progressed. We found a decrease in fractional anisotropy in the corticospinal tract, corpus callosum and thalamus in all 15 ALS patients, including the patients without clinical signs of upper motor neuron lesion, compared with healthy controls. Regression analysis showed a negative correlation between fractional anisotropy and central motor conduction time obtained by transcranial magnetic stimulation, allowing spatial differentiation between the degenerated corticospinal tract fibres that supply the upper and lower extremities. Thus, diffusion tensor MRI can be used to assess upper motor neuron involvement in ALS patients before clinical symptoms of corticospinal tract lesion become apparent, and it may therefore contribute to earlier diagnosis of motor neuron disease.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

Publication types