Wang Po-Shan, Wu Yu-Te, Wang Tzu-Yun, Wu Hsiu-Mei, Soong Bing-Wen, Jao Chi-Wen
Brain Research Center, National Yang-Ming University, Taipei, Taiwan.
Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan.
Front Neurol. 2020 Mar 3;11:124. doi: 10.3389/fneur.2020.00124. eCollection 2020.
Spinocerebellar ataxia type 3 (SCA) is a cerebellum-dominant degenerative disorder that is characterized primarily by infratentorial damage, although less severe supratentorial involvement may contribute to the clinical manifestation. These impairments may result from the efferent loss of the cerebellar cortex and degeneration of the cerebral cortex. We used the three-dimensional fractal dimension (3D-FD) method to quantify the morphological changes in the supratentorial regions and assessed atrophy in the relatively focal regions in patients with SCA3. A total of 48 patients with SCA3 and 50 sex- and age-matched healthy individuals, as the control group, participated in this study. The 3D-FD method was proposed to distinguish 97 automatic anatomical label regions of gray matter (left cerebrum: 45, right cerebrum: 45, cerebellum: 7) between healthy individuals and patients with SCA3. Patients with SCA3 exhibited reduced brain complexity within both the traditional olivopontocerebellar atrophy (OPCA) pattern and specific supratentorial regions. The study results confirmed the extensive involvement of extracerebellar regions in SCA3. The atrophied regions of SCA3 in infratentorial and supratentorial cortex showed a wide range of overlapped areas as in two functional cortexes, namely cerebellum-related cortex and basal ganglia-related cortex. Our results found that the atrophy of the SCA3 are not only limited in the infratentorial regions. Both cerebellar related cortex and basal ganglia related cortex were affected in the disease process of SCA3. Our findings might correlate to the common symptoms of SCA3, such as ataxia, Parkinsonism, dysarthria, and dysmetria. SCA3 should no longer be considered a disease limited to the cerebellum and its connections; rather, it should be considered a pathology affecting the whole brain.
3型脊髓小脑共济失调（SCA）是一种以小脑病变为主的退行性疾病，主要特征为幕下损害，不过幕上较轻的受累情况也可能影响临床表现。这些损害可能源于小脑皮质的传出性丧失和大脑皮质的退化。我们使用三维分形维数（3D-FD）方法来量化SCA3患者幕上区域的形态变化，并评估相对局灶区域的萎缩情况。共有48例SCA3患者和50例年龄及性别匹配的健康个体作为对照组参与了本研究。3D-FD方法用于区分健康个体和SCA3患者之间97个自动解剖标记的灰质区域（左大脑：45个，右大脑：45个，小脑：7个）。SCA3患者在传统的橄榄脑桥小脑萎缩（OPCA）模式和特定的幕上区域内均表现出脑复杂性降低。研究结果证实SCA3存在广泛的小脑外区域受累情况。SCA3在幕下和幕上皮质的萎缩区域显示出广泛的重叠区域，如同两个功能皮质，即小脑相关皮质和基底神经节相关皮质。我们的研究结果发现，SCA3的萎缩不仅局限于幕下区域。在SCA3的疾病过程中，小脑相关皮质和基底神经节相关皮质均受到影响。我们的研究结果可能与SCA3的常见症状相关，如共济失调、帕金森综合征、构音障碍和辨距不良。SCA3不应再被视为仅限于小脑及其连接的疾病；相反，它应被视为一种影响全脑的病理状态。
