Voxel-based morphometry and Voxel-based relaxometry in parkinsonian variant of multiple system atrophy.
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.
Tzarouchi
Loukia C
LC
Department of Radiology, Medical School, University of Ioannina, Ioannina, Greece.
Astrakas
Loukas G
LG
Konitsiotis
Spyridon
S
Tsouli
Sofia
S
Margariti
Persefoni
P
Zikou
Anastasia
A
Argyropoulou
Maria I
MI
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