Gray matter atrophy in parkinsons disease and the parkinsonian variant of multiple system atrophy: a combined roi- and voxel-based morphometric study

OBJECTIVES: Parkinson's disease (PD) and the parkinsonian variant of multiple system atrophy (MSA-P) are distinct neurodegenerative disorders that share similar clinical features of parkinsonism. The morphological alterations of these diseases have yet to be understood. The purpose of this study was to evaluate gray matter atrophy in PD and MSA-P using regions of interest (ROI)-based measurements and voxel-based morphometry (VBM). METHODS: We studied 41 patients with PD, 20 patients with MSA-P, and 39 controls matched for age, sex, and handedness using an improved T1-weighted sequence that eased gray matter segmentation. The gray matter volumes were measured using ROI and VBM. RESULTS: ROI volumetric measurements showed significantly reduced bilateral putamen volumes in MSA-P patients compared with those in PD patients and controls (p<0.05), and the volumes of the bilateral caudate nucleus were significantly reduced in both MSA-P and PD patients compared with those in the controls (p<0.05). VBM analysis revealed multifocal cortical and subcortical atrophy in both MSA-P and PD patients, and the volumes of the cerebellum and temporal lobes were remarkably reduced in MSA-P patients compared with the volumes in PD patients (p<0.05). CONCLUSIONS: Both PD and MSA-P are associated with gray matter atrophy, which mainly involves the bilateral putamen, caudate nucleus, cerebellum, and temporal lobes. ROI and VBM can be used to identify these morphological alterations, and VBM is more sensitive and repeatable and less time-consuming, which may have potential diagnostic value.

Study of Gray Matter Loss in Alzheimer's Disease Based on Automatic Voxel-based Morphometry / 航天医学与医学工程

Objective To explore the gray matter loss of Alzheimer's disease (AD) patients by processing the magnetic resonance imaging (MRI) with computer. Method A voxel-based morphometry (VBM) method was applied in this study. Result Bilateral loss of gray matter in AD patients was found in the entorhinal/ hippocampal/parahippocampal cortex areas, amygdala, the head of the caudate nucleus, middle temporal gyrus, cingulate gyrus, inferior parietal lobule, insula and dorsolateral prefrontal cortex. Furthermore, area of right pulvinar, cortex of superior temporal gyrus and superior parietal lobule reduced significantly. On the other hand, somatosensory/motor cortex, cerebellum and occipital lobe were relatively intact. Conclusion VBM overcomes the shortcomings of region of interesting(ROI), such as time-consuming, dependence on observer, and poorly reproducible, and can analyze the gray matter loss objectively and automatically and have a good perspective for clinical applications.