Coppen Emma M, van der Grond Jeroen, Hart Ellen P, Lakke Egbert A J F, Roos Raymund A C
Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands.
Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
Behav Brain Res. 2018 Oct 1;351:63-74. doi: 10.1016/j.bbr.2018.05.019. Epub 2018 May 21.
The processing of visual stimuli from retina to higher cortical areas has been extensively studied in the human brain. In Huntington's disease (HD), an inherited neurodegenerative disorder, it is suggested that visual processing deficits are present in addition to more characteristic signs such as motor disturbances, cognitive dysfunction, and behavioral changes. Visual deficits are clinically important because they influence overall cognitive performance and have implications for daily functioning. The aim of this review is to summarize current literature on clinical visual deficits, visual cognitive impairment, and underlying visual cortical changes in HD patients. A literature search was conducted using the electronic database of PubMed/Medline. This review shows that changes of the visual system in patients with HD were not the primary focus of currently published studies. Still, early atrophy and alterations of the posterior cerebral cortex was frequently observed, primarily in the associative visual cortical areas such as the lingual and fusiform gyri, and lateral occipital cortex. Changes were even present in the premanifest phase, before clinical onset of motor symptoms, suggesting a primary region for cortical degeneration in HD. Although impairments in visuospatial processing and visual perception were reported in early disease stages, heterogeneous cognitive batteries were used, making a direct comparison between studies difficult. The use of a standardized battery of visual cognitive tasks might therefore provide more detailed information regarding the extent of impairments in specific visual domains. Further research could provide more insight into clinical, functional, and pathophysiological changes of the visual pathway in HD.
从视网膜到更高皮层区域的视觉刺激处理过程已在人类大脑中得到广泛研究。在亨廷顿舞蹈病（HD）中，这是一种遗传性神经退行性疾病，除了诸如运动障碍、认知功能障碍和行为改变等更具特征性的症状外，还提示存在视觉处理缺陷。视觉缺陷在临床上很重要，因为它们会影响整体认知表现并对日常功能产生影响。本综述的目的是总结当前关于HD患者临床视觉缺陷、视觉认知障碍及潜在视觉皮层变化的文献。使用PubMed/Medline电子数据库进行了文献检索。本综述表明，HD患者视觉系统的变化并非当前已发表研究的主要关注点。尽管如此，仍经常观察到大脑后皮层的早期萎缩和改变，主要发生在诸如舌回、梭状回和枕外侧皮层等联合视觉皮层区域。甚至在运动症状临床发作之前的临床前期就已出现变化，这表明HD中存在皮层退化的主要区域。尽管在疾病早期阶段就报告了视觉空间处理和视觉感知方面的损伤，但使用的认知测试组合各不相同，使得各研究之间难以进行直接比较。因此，使用标准化的视觉认知任务测试组合可能会提供有关特定视觉领域损伤程度的更详细信息。进一步的研究可能会更深入地了解HD中视觉通路的临床、功能和病理生理变化。
