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Kallmann's syndrome: mirror movements associated with bilateral corticospinal tract hypertrophy

M Krams1, R Quinton, J Ashburner

  • 1Wellcome Department of Cognitive Neurology, Institute of Neurology, London, UK.

Neurology
|March 17, 1999
PubMed
Abstract

Insights

Mirror movements in X-linked Kallmann's syndrome (xKS) are linked to abnormal development of the corticospinal tract. This study found bilateral corticospinal tract hypertrophy in xKS patients with mirror movements.

Area of Science:

  • Neuroscience
  • Genetics
  • Radiology

Background:

  • Mirror movements affect 85% of patients with X-linked Kallmann's syndrome (xKS).
  • Previous studies suggested abnormal ipsilateral corticospinal tract projection or a lack of transcallosal inhibition in xKS patients with mirror movements.

Purpose of the Study:

  • To investigate the cause of mirror movements in xKS patients.
  • To analyze white matter data from structural MRI scans using statistical methods.

Main Methods:

  • Structural MRI scans (T1-weighted) were analyzed using SPM-96 software.
  • White matter data from nine xKS patients were compared to nine autosomal Kallmann's syndrome (aKS) patients and nine healthy controls.
  • Voxel-by-voxel comparison of normalized brain scans was performed.

Main Results:

  • Both xKS and aKS groups showed corpus callosum hypertrophy, with specific regions differing between groups.
  • Bilateral corticospinal tract hypertrophy was observed exclusively in xKS patients exhibiting mirror movements.
  • SPM analysis results were confirmed by region of interest analysis.

Conclusions:

  • While morphometry alone doesn't confirm causation, the hypertrophied corticospinal tract in xKS supports the hypothesis of abnormal ipsilateral corticospinal tract fiber development.
  • This finding aligns with electrophysiologic evidence regarding the etiology of mirror movements in xKS.

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