Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands.
Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands.
Neuroimage Clin. 2018 Jun 19;19:963-969. doi: 10.1016/j.nicl.2018.06.025. eCollection 2018.
Mechanisms underlying cognitive impairment in patients with small vessel disease (SVD) are still unknown. We hypothesized that cognition is affected by the cumulative effect of multiple SVD-related lesions on brain connectivity. We therefore assessed the relationship between the total SVD burden on MRI, global brain network efficiency, and cognition in memory clinic patients with vascular brain injury.
173 patients from the memory clinic of the University Medical Center Utrecht underwent a 3 T brain MRI scan (including diffusion MRI sequences) and neuropsychological testing. MRI markers for SVD were rated and compiled in a previously developed total SVD score. Structural brain networks were reconstructed using fiber tractography followed by graph theoretical analysis. The relationship between total SVD burden score, global network efficiency and cognition was assessed using multiple linear regression analyses.
Each point increase on the SVD burden score was associated with 0.260 [-0.404 - -0.117] SD units decrease of global brain network efficiency ( < .001). Global network efficiency was associated with information processing speed (standardized B = -0.210, = .004) and attention and executive functioning (B = 0.164, .042), and mediated the relationship between SVD burden and information processing speed ( = .027) but not with executive functioning ( = .12).
Global network efficiency is sensitive to the cumulative effect of multiple manifestations of SVD on brain connectivity. Global network efficiency may therefore serve as a useful marker for functionally relevant SVD-related brain injury in clinical trials.
小血管疾病（SVD）患者认知障碍的机制尚不清楚。我们假设认知受到多种 SVD 相关病变对脑连接影响的累积效应的影响。因此，我们评估了磁共振成像上 SVD 总负担、全脑网络效率与血管性脑损伤记忆诊所患者认知之间的关系。
乌得勒支大学医学中心记忆诊所的 173 名患者接受了 3T 脑部 MRI 扫描（包括弥散 MRI 序列）和神经心理学测试。使用以前开发的总 SVD 评分对 SVD 的 MRI 标志物进行评分和编制。使用纤维束追踪法重建结构脑网络，然后进行图论分析。使用多元线性回归分析评估总 SVD 负担评分、全脑网络效率与认知之间的关系。
SVD 负担评分每增加 1 分，全脑网络效率降低 0.260 [-0.404 至 -0.117]个标准差单位（<0.001）。全脑网络效率与信息处理速度（标准化 B=-0.210，p=0.004）和注意力及执行功能（B=0.164，p=0.042）相关，且中介了 SVD 负担与信息处理速度之间的关系（p=0.027），但与执行功能无关（p=0.12）。
全脑网络效率对 SVD 多种表现对脑连接的累积效应敏感。因此，全脑网络效率可能是临床试验中与功能相关的 SVD 相关脑损伤的有用标志物。
