Original Research ARTICLE
Impaired Efficiency and Resilience of Structural Network in Spinocerebellar Ataxia Type 3
- 1National Yang-Ming University, Taiwan
- 2Taipei Veterans General Hospital, Taiwan
Background: Recent studies have shown that the patients with spinocerebellar ataxia type 3 (SCA3) may not only have disease involvement in the cerebellum and brainstem but also in the cerebral regions. However, the relations between the widespread degenerated brain regions remains incompletely explored.
Methods: In the present study, we investigate the topological properties of the brain networks of SCA3 patients (n = 40) constructed based on the correlation of three-dimensional fractal dimension values. Random and targeted attacks were applied to measure the network resilience of normal and SCA3 groups. Results: The SCA3 networks had significantly smaller clustering coefficients (P < 0.05) and global efficiency (P < 0.05) but larger characteristic path length (P < 0.05) than the normal controls networks, implying loss of small-world features. Furthermore, the SCA3 patients were associated with reduced nodal betweenness (P < 0.001) in the left supplementary motor area, bilateral paracentral lobules, and right thalamus, indicating that the motor control circuit might be compromised.
Conclusions: The SCA3 networks were more vulnerable to targeted attacks than the normal controls networks because of the effects of pathological topological organisation. The SCA3 revealed a more sparsity and disrupted structural network with decreased values in the largest component size, mean degree, mean density, clustering coefficient and global efficiency and increased value in characteristic path length. The cortico-cerebral circuits in SCA3 were disrupted and segregated into occcipital-parietal (visual-spatial cognition) and frontal-pre-drontal (motor control) clusters. The cerebellum of SCA3 were segregated from cerebellum-temporal-frontal circuits and clustered into a frontal-temporal cluster (cognitive control). Therefore, the disrupted structural network presented in this study might reflect the clinical characteristics of SCA3.
Keywords: brain connectivity, fractal dimension, graph theoretical analysis, Spinocerebellar ataxia type 3, Structural network
Received: 13 Sep 2018;
Accepted: 27 Nov 2018.
Edited by:Vittorio Maglione, Istituto Neurologico Mediterraneo (IRCCS), Italy
Reviewed by:Massimo Marano, Campus Bio-Medico University, Italy
Marcondes C. França Jr, Universidade Estadual de Campinas, Brazil
Copyright: © 2018 Wu, Huang, Jao, Soong, Lirng, Wu and Wang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Po-Shan Wang, National Yang-Ming University, Taipei, Taiwan, firstname.lastname@example.org