Cerebellar White Matter Degeneration Altered Brain Network Organization and Cortical Morphology in Multiple System Atrophy of the Cerebellar Type

• Main Authors: Chia-Feng Lu, 盧家鋒
• Other Authors: Yu-Te Wu
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/50728844034410424288

博士 === 國立陽明大學 === 生物醫學影像暨放射科學系 === 101 === The cerebellum involves diverse functions from motor coordination to higher cognitive functions. Impairment of the cerebellum can cause ataxia and cerebellar cognitive affective syndrome. Multiple system atrophy of the cerebellar type (MSA-C) is a neurodegenerative disorder with atrophy of pontocerebellar white matter (WM). We acquired T1-weighted and diffusion tensor images for 18 patients with MSA-C and 19 normal controls. This thesis explores the role of cerebellum in the presence of the pontocerebellar WM atrophy from the perspective of local structures to global functions, including 1) the volumetric and morphological changes of the white matter in cerebellum and cerebrum; 2) the destruction of local WM integrity and whole-brain fiber tracking; 3) the alteration of the global small-world architecture and regionally topological properties; 4) the variation in modular structure of the structural connectivity. The concurrent use of the measures of local morphology and properties of global network based on graph theory and modular organization for both MSA-C and healthy groups can offer a more complete view to understand the structure and function of cerebellum. The results showed that pontocerebellar WM degeneration caused the destruction of cerebello-ponto-cerebral loops, resulting in reduced communication efficiency between regions in the whole-brain network. In addition, the sulcal area of the inner cortical surface in the cerebellum decreased linearly with the pontocerebellar WM volume, and the inferoposterior lobe exhibited a steeper atrophy rate than that of vermis regions. We concluded that the integrity of pontocerebellar WM is critical in sustaining the local morphology and the global functions of the whole-brain fiber network.