Thalamic Involvement in Multiple Sclerosis: A Diffusion-Weighted Magnetic Resonance Imaging Study

Abstract

MS patients have increased water diffusion in the thalamus that is partly associated with clinical course, lesion load, and whole-brain atrophy. Both indirect and direct mechanisms of gray matter injury may play a role in the pathophysiology of MS.

A Magnetization Transfer MRI Study of Deep Gray Matter Involvement in Multiple Sclerosis

“…Previously thought of as a white matter disease, there is now a growing body of evidence suggesting gray matter involvement 1,2 . A variety of abnormalities have been demonstrated in the gray matter of MS patients including hypometabolism, 3 atrophy, 4,5 direct plaque formation, 6 depletion of neuronal metabolites, 4 reduced magnetization transfer ratio (MTR), 7 increased diffusivity, 8 and T2 hypointensity 9 . Studies of gray matter changes in MS have shown damage to both the cerebral cortex and subcortical nuclei 2 .…”

Thalamic Involvement and Its Impact on Clinical Disability in Patients with Multiple Sclerosis: A Diffusion Tensor Imaging Study at 3T

“…Some studies found no differences between patients with MS and healthy controls, [8][9][10] whereas others suggested that thalamic involvement is detectable in patients with MS. 5,[11][12][13][14][15][16][17] The time course of thalamic involvement in MS is still an unanswered question. Although some studies have suggested that thalamic involvement starts early, 14,18,19 others have only identified damage in later stages of the disease.…”

Differentiating multiple sclerosis from other causes of demyelination using diffusion weighted imaging of the corpus callosum

“…Abnormalities in diffusion weighted imaging (DWI) and the related technique diffusion tensor imaging (DTI) have repeatedly been described in brains of those with MS even in areas that appear normal on conventional MRI. Higher apparent diffusion coefficients (ADCs) have been demonstrated in normal‐appearing gray and white matter of the brain and spinal cord of MS patients when compared with normal controls (19–26). In particular, diffusion related metrics within the corpus callosum, have been consistently shown to differ between MS and control subjects (19, 20, 21, 26).…”

“…In well‐myelinated brain tracts, ADC is relatively low because water diffusion is restricted to the direction of the tract fibers, whereas in demyelinated brain tracts, ADC is relatively high because water diffusion is not restricted. Multiple studies have demonstrated abnormal diffusion and pathophysiology in the normal appearing white matter and spinal cord in patients with MS (19–26).…”