title: Microstructure of the Midbrain and Cervical Spinal Cord in Idiopathic Restless Legs Syndrome: A Diffusion Tensor Imaging Study.
abstract: OBJECTIVE
  Diffusion tensor imaging (DTI) allows the study of white matter microstructure in the central nervous system. The aim of this study was to examine the DTI metrics of the cervical spinal cord and the brainstem up to the midbrain in patients with idiopathic restless legs (RLS) compared to matched healthy controls.
  
  
  METHODS
  DTI analysis of the cervical spinal cord and the brainstem up into the midbrain was performed in 25 patients with idiopathic RLS and 25 matched healthy controls. Data analysis in the brain was performed by voxelwise comparison of fractional anisotropy (FA) maps at group level. Cervical spinal cord data analysis was performed by slicewise analysis of averaged FA values in axial slices along the spinal cord.
  
  
  RESULTS
  Voxelwise comparison of FA maps in the brainstem showed significant microstructural alterations in two clusters in the midbrain bilaterally. Slicewise comparison of the FA maps in the cervical spinal cord showed a trend for lower FA values at the level of the second and third vertebra area in the patient sample.
  
  
  CONCLUSIONS
  The imaging data suggest that significant alterations in the midbrain in RLS can be visualized by DTI and might correlate to a macroscopically subtle process with changes of the tissue microstructure in the corresponding tracts. An additional area of interest is regionally clustered in the upper cervical spinal cord with a tendency toward altered diffusion metrics. These results might be addressed by further studies, e.g., at higher magnetic field strengths.
authors.affiliation: Department of Neurology, University of Ulm, Ulm, Germany.
authors.forename: Klaas
authors.initials: K
authors.lastname: Lindemann
authors.affiliation: Department of Neurology, University of Ulm, Ulm, Germany.
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Müller
authors.affiliation: Department of Neurology, University of Ulm, Ulm, Germany.
authors.forename: Albert C
authors.initials: AC
authors.lastname: Ludolph
authors.affiliation: Department of Neurology, University of Ulm, Ulm, Germany.|Neuropsychiatrisches Zentrum Erding/München, Erding, Germany.
authors.forename: Magdolna
authors.initials: M
authors.lastname: Hornyak
authors.affiliation: Department of Neurology, University of Ulm, Ulm, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Kassubek
mesh_terms: D016880:Anisotropy; D001933:Brain Stem / Q000473:pathology; D066193:Cervical Cord / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008636:Mesencephalon / Q000473:pathology*; D008875:Middle Aged; D012148:Restless Legs Syndrome / Q000473:pathology*; D066127:White Matter / Q000473:pathology
keywords: diffusion tensor imaging; magnetic resonance imaging; midbrain; restless legs syndrome; spinal cord; substantia nigra