Structural white matter abnormalities in patients with idiopathic dystonia

Authors

  • Leonardo Bonilha MD, PhD,

    1. Department of Communication Sciences and Disorders, University of South Carolina, Columbia, South Carolina, USA
    2. Department of Neuropsychiatry, University of South Carolina, Columbia, South Carolina, USA
    Search for more papers by this author
  • Paulien M. de Vries,

    1. Department of Neurology, Neuroimaging Center, Institute of Behavioral and Cognitive Neuroscience, University of Groningen, Groningen, The Netherlands
    Search for more papers by this author
  • Diana J. Vincent MD, PhD,

    1. Department of Radiology, Medical University of South Carolina, Charleston, South Carolina, USA
    2. Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina, USA
    3. Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
    Search for more papers by this author
  • Chris Rorden MD, PhD,

    1. Department of Communication Sciences and Disorders, University of South Carolina, Columbia, South Carolina, USA
    Search for more papers by this author
  • Paul S. Morgan,

    1. Division of Academic Radiology, University of Nottingham, Nottingham, United Kingdom
    Search for more papers by this author
  • Mark W. Hurd PhD,

    1. Department of Radiology, Medical University of South Carolina, Charleston, South Carolina, USA
    2. Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
    3. Department of Psychology, College of Charleston, Charleston, South Carolina, USA
    Search for more papers by this author
  • Nada Besenski MD,

    1. Department of Radiology, Medical University of South Carolina, Charleston, South Carolina, USA
    Search for more papers by this author
  • Kenneth J. Bergmann MD,

    1. Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
    2. Murray Center for Research on Parkinson's Disease and Related Disorders, Medical University of South Carolina, Charleston, South Carolina, USA
    Search for more papers by this author
  • Vanessa K. Hinson MD, PhD

    Corresponding author
    1. Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
    2. Murray Center for Research on Parkinson's Disease and Related Disorders, Medical University of South Carolina, Charleston, South Carolina, USA
    • Charleston Memorial Hospital, 326 Calhoun Street, Suite 308, Charleston, SC 29425
    Search for more papers by this author

Abstract

We investigated whether structural white matter abnormalities, in the form of disruption of axonal coherence and integrity as measured with diffusion tensor imaging (DTI), constitute an underlying pathological mechanism of idiopathic dystonia (ID), independent of genotype status. We studied seven subjects with ID: all had cervical dystonia as their main symptom (one patient also had spasmodic dysphonia and two patients had concurrent generalized dystonia, both DYT1-negative). We compared DTI MR images of patients with 10 controls, evaluating differences in mean diffusivity (MD) and fractional anisotropy (FA). ID was associated with increased FA values in the thalamus and adjacent white matter, and in the white matter underlying the middle frontal gyrus. ID was also associated with increase in MD in adjacent white matter to the pallidum and putamen bilaterally, left caudate, and in subcortical hemispheric regions, including the postcentral gyrus. Abnormal FA and MD in patients with ID indicate that abnormal axonal coherence and integrity contribute to the pathophysiology of dystonia. These findings suggest that ID is not only a functional disorder, but also associated with structural brain changes. Impaired connectivity and disrupted flow of information may contribute to the impairment of motor planning and regulation in dystonia. © 2006 Movement Disorder Society

Ancillary