Department of Clinical Neuropsychiatry, Medical University of Lublin, 20-439 Lublin, Poland; Department of Biomedical Engineering, Lublin University of Technology, 20-618 Lublin, Poland.
Department of Clinical Neuropsychiatry, Medical University of Lublin, 20-439 Lublin, Poland.
Neuroscience. 2021 Feb 10;455:128-140. doi: 10.1016/j.neuroscience.2020.12.019. Epub 2020 Dec 25.
Examining individuals with Leber's hereditary optic neuropathy (LHON) provides a rare opportunity to understand how changes in mitochondrial DNA and loss of vision can be related to changes in organization of the whole-brain structural network architecture. In comparison with the previous neuroimaging studies with LHON participants, which were focused mainly on analyzing changes which occur in different areas of the patient's brain, network analysis not only makes it possible to observe single white matter fibers' aberrations but also the whole-brain nature of these changes. The purpose of our study was to better understand whole-brain neural network changes in LHON participants and see the correlation between the clinical data and the changes. To achieve this, we examined fifteen LHON patients and seventeen age-matched healthy subjects with the usage of ultra-high filed 7T magnetic resonance imaging (MRI). Basing on the analysis on MRI diffusion tensor imaging (DTI) data, whole-brain structural neural networks were reconstructed with the use of the minimum spanning tree algorithm (MST) for every participant. Our results revealed that the structural network in LHON participants was altered at both the local and the global level. The global network structures of LHON subjects were less centralized with path-like organization and there was an imbalance in the main hub centrality. Moreover, the inspection of nodes and hubs in terms of their anatomical placement revealed that in the LHON participants the prominent hubs were located within the basal ganglia (i.e. bilateral caudate, left pallidum), which differed them from healthy controls. An analysis of the relationships between the global MST metrics and LHON participants' clinical characteristics revealed significant correlations between the global network metrics and the duration of illness. Furthermore, the nodal parameters of the optic chiasm were significantly correlated with the duration of illness and the averaged thickness of the right retinal nerve fiber layer (RNFL). These findings clearly showed that the progression of the disease is accompanied by alterations within the brain network structure and its efficiency.
检查患有莱伯遗传性视神经病变 (LHON) 的个体为我们提供了一个难得的机会，可以了解线粒体 DNA 的变化以及视力丧失如何与整个大脑结构网络架构的组织变化相关联。与之前主要集中在分析患者大脑不同区域发生变化的 LHON 参与者的神经影像学研究相比，网络分析不仅可以观察到单个白质纤维的异常，还可以观察到这些变化的全脑性质。我们的研究目的是更好地了解 LHON 参与者的全脑神经网络变化，并观察临床数据与变化之间的相关性。为了实现这一目标，我们使用超高场 7T 磁共振成像 (MRI) 检查了 15 名 LHON 患者和 17 名年龄匹配的健康对照者。基于对 MRI 扩散张量成像 (DTI) 数据的分析，我们使用最小生成树算法 (MST) 为每位参与者重建了全脑结构神经网络。我们的研究结果表明，LHON 患者的结构网络在局部和全局水平都发生了改变。LHON 受试者的全局网络结构不太集中，具有路径样组织，并且主枢纽中心性存在不平衡。此外，从解剖位置上检查节点和枢纽，发现 LHON 患者的突出枢纽位于基底节内（即双侧尾状核、左侧苍白球），与健康对照组不同。对全局 MST 度量与 LHON 参与者临床特征之间的关系进行分析，发现全局网络度量与疾病持续时间之间存在显著相关性。此外，视交叉的节点参数与疾病持续时间和右侧视网膜神经纤维层（RNFL）的平均厚度显著相关。这些发现清楚地表明，疾病的进展伴随着大脑网络结构及其效率的改变。
