Ataxia Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy; Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy.
Ataxia Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy.
Neuroscience. 2017 Dec 16;366:44-53. doi: 10.1016/j.neuroscience.2017.10.007. Epub 2017 Oct 12.
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disease involving the cerebellum. The particular atrophy pattern results in some typical clinical features mainly including motor deficits. In addition, the presence of cognitive impairments, involving language, visuospatial and executive functions, has been also shown in SCA2 patients and it is now widely accepted as a feature of the disease. The aim of the study is to investigate the microstructural patterns and the anatomo-functional substrate that could account for the cognitive symptomatology observed in SCA2 patients. In the present study, diffusion tensor imaging (DTI) based-tractography was performed to map the main cerebellar white matter (WM) bundles, such as Middle and Superior Cerebellar Peduncles, connecting cerebellum with higher order cerebral regions. Damage-related diffusivity measures were used to determine the pattern of pathological changes of cerebellar WM microstructure in patients affected by SCA2 and correlated with the patients' cognitive scores. Our results provide the first evidence that WM diffusivity is altered in the presence of the cerebellar cortical degeneration associated with SCA2 thus resulting in a cerebello-cerebral dysregulation that may account for the specificity of cognitive symptomatology observed in patients.
脊髓小脑共济失调 2 型（SCA2）是一种常染色体显性遗传性神经退行性疾病，涉及小脑。特定的萎缩模式导致一些典型的临床特征，主要包括运动缺陷。此外，SCA2 患者还存在认知障碍，涉及语言、视空间和执行功能，这已被广泛接受为该疾病的特征。本研究旨在探讨能够解释 SCA2 患者观察到的认知症状的微观结构模式和解剖功能基础。在本研究中，进行了基于弥散张量成像（DTI）的束追踪，以绘制连接小脑与高级脑区的主要小脑白质（WM）束，如中间和上小脑脚。使用与损伤相关的弥散度测量来确定 SCA2 患者小脑 WM 微观结构病理变化的模式，并与患者的认知评分相关。我们的研究结果首次提供了证据，表明 WM 弥散度在与 SCA2 相关的小脑皮质变性存在时发生改变，从而导致小脑-大脑调节失调，这可能解释了患者观察到的认知症状的特异性。
