Lu Tong, Wang Zan, Zhu Yixin, Wang Mengxue, Lu Chun-Qiang, Ju Shenghong
Department of Radiology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, China.
Department of Neurology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, China.
Brain Commun. 2024 Feb 21;6(1):fcae042. doi: 10.1093/braincomms/fcae042. eCollection 2024.
White matter hyperintensities, one of the major markers of cerebral small vessel disease, disrupt the integrity of neuronal networks and ultimately contribute to cognitive dysfunction. However, a deeper understanding of how white matter hyperintensities related to the connectivity patterns of brain hubs at the neural network level could provide valuable insights into the relationship between white matter hyperintensities and cognitive dysfunction. A total of 36 patients with moderate to severe white matter hyperintensities (Fazekas score ≥ 3) and 34 healthy controls underwent comprehensive neuropsychological assessments and resting-state functional MRI scans. The voxel-based graph-theory approach-functional connectivity strength was employed to systematically investigate the topological organization of the whole-brain networks. The white matter hyperintensities patients performed significantly worse than the healthy controls in episodic memory, executive function and information processing speed. Additionally, we found that white matter hyperintensities selectively affected highly connected hub regions, predominantly involving the medial and lateral prefrontal, precuneus, inferior parietal lobule, insula and thalamus. Intriguingly, this impairment was connectivity distance-dependent, with the most prominent disruptions observed in long-range connections (e.g. 100-150 mm). Finally, these disruptions of hub connectivity (e.g. the long-range functional connectivity strength in the left dorsolateral prefrontal cortex) positively correlated with the cognitive performance in white matter hyperintensities patients. Our findings emphasize that the disrupted hub connectivity patterns in white matter hyperintensities are dependent on connection distance, especially longer-distance connections, which in turn predispose white matter hyperintensities patients to worse cognitive function.
脑白质高信号是脑小血管病的主要标志物之一,它破坏神经元网络的完整性,最终导致认知功能障碍。然而,在神经网络层面更深入地了解脑白质高信号与脑枢纽连接模式之间的关系,能够为脑白质高信号与认知功能障碍之间的关系提供有价值的见解。共有36例中度至重度脑白质高信号患者( Fazekas评分≥3)和34名健康对照者接受了全面的神经心理学评估和静息态功能磁共振成像扫描。采用基于体素的图论方法——功能连接强度,系统地研究全脑网络的拓扑组织。脑白质高信号患者在情景记忆、执行功能和信息处理速度方面的表现明显比健康对照者差。此外,我们发现脑白质高信号选择性地影响高度连接的枢纽区域,主要涉及内侧和外侧前额叶、楔前叶、顶下小叶、岛叶和丘脑。有趣的是,这种损害与连接距离有关,在长程连接(如100 - 150 mm)中观察到最明显的破坏。最后,这些枢纽连接的破坏(如左侧背外侧前额叶皮质的长程功能连接强度)与脑白质高信号患者的认知表现呈正相关。我们的研究结果强调,脑白质高信号中枢纽连接模式的破坏取决于连接距离,尤其是较长距离的连接,这反过来使脑白质高信号患者更容易出现较差的认知功能。