title: Voxel-based morphometry and Voxel-based relaxometry in parkinsonian variant of multiple system atrophy.
abstract: OBJECTIVE
  Multiple system atrophy (MSA) is a progressive neurodegenerative disorder divided into a parkinsonian (MSA-P) and a cerebellar variant. The purpose of this study was to assess regional brain atrophy and iron content using Voxel-based morphometry (VBM) and Voxel-based relaxometry (VBR) respectively, in MSA-P.
  
  
  METHODS
  Using biological parametric mapping the effect of brain atrophy was evaluated in T2 relaxation time (T2) measurements by applying analysis of covariance (ANCOVA) and correlation analysis to the VBM and VBR data. Eleven patients with MSA-P (aged 61.9 +/- 11.7 years, disease duration 5.42 +/- 2.5 years) and 11 controls were studied.
  
  
  RESULTS
  In comparison to the controls the patients showed decreased gray matter in the putamen, the caudate nuclei, the thalami, the anterior cerebellar lobes, and the cerebral cortex, and white matter atrophy in the pons, midbrain, and peduncles. VBR analysis showed prolonged T2 in various cortical regions. On ANCOVA, when controlling for gray and white matter volume, these regions of prolonged T2 were shrunk. Negative correlation was demonstrated between T2 and gray and white matter volume.
  
  
  CONCLUSIONS
  Diffuse brain atrophy, mainly in the motor circuitry is observed in MSA-P. Normalization for atrophy should always be performed in T2 measurements.
authors.affiliation: Department of Radiology, Medical School, University of Ioannina, Ioannina, Greece.
authors.forename: Loukia C
authors.initials: LC
authors.lastname: Tzarouchi
authors.forename: Loukas G
authors.initials: LG
authors.lastname: Astrakas
authors.forename: Spyridon
authors.initials: S
authors.lastname: Konitsiotis
authors.forename: Sofia
authors.initials: S
authors.lastname: Tsouli
authors.forename: Persefoni
authors.initials: P
authors.lastname: Margariti
authors.forename: Anastasia
authors.initials: A
authors.lastname: Zikou
authors.forename: Maria I
authors.initials: MI
authors.lastname: Argyropoulou
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000473:pathology*; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D036421:Nerve Fibers, Unmyelinated / Q000473:pathology