Filippi Massimo, Basaia Silvia, Canu Elisa, Imperiale Francesca, Meani Alessandro, Caso Francesca, Magnani Giuseppe, Falautano Monica, Comi Giancarlo, Falini Andrea, Agosta Federica
From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy.
Neurology. 2017 Oct 24;89(17):1764-1772. doi: 10.1212/WNL.0000000000004577. Epub 2017 Sep 27.
To investigate functional brain network architecture in early-onset Alzheimer disease (EOAD) and behavioral variant frontotemporal dementia (bvFTD).
Thirty-eight patients with bvFTD, 37 patients with EOAD, and 32 age-matched healthy controls underwent 3D T1-weighted and resting-state fMRI. Graph analysis and connectomics assessed global and local functional topologic network properties, regional functional connectivity, and intrahemispheric and interhemispheric between-lobe connectivity.
Despite similarly extensive cognitive impairment relative to controls, patients with EOAD showed severe global functional network alterations (lower mean nodal strength, local efficiency, clustering coefficient, and longer path length), while patients with bvFTD showed relatively preserved global functional brain architecture. Patients with bvFTD demonstrated reduced nodal strength in the frontoinsular lobe and a relatively focal altered functional connectivity of frontoinsular and temporal regions. Functional connectivity breakdown in the posterior brain nodes, particularly in the parietal lobe, differentiated patients with EOAD from those with bvFTD. While EOAD was associated with widespread loss of both intrahemispheric and interhemispheric functional correlations, bvFTD showed a preferential disruption of the intrahemispheric connectivity.
Disease-specific patterns of functional network topology and connectivity alterations were observed in patients with EOAD and bvFTD. Graph analysis and connectomics may aid clinical diagnosis and help elucidate pathophysiologic differences between neurodegenerative dementias.
研究早发型阿尔茨海默病（EOAD）和行为变异型额颞叶痴呆（bvFTD）的脑功能网络结构。
38例bvFTD患者、37例EOAD患者和32例年龄匹配的健康对照者接受了三维T1加权成像和静息态功能磁共振成像。采用图谱分析和连接组学评估整体和局部功能拓扑网络特性、区域功能连接以及半球内和半球间叶间连接。
尽管与对照组相比，EOAD患者和bvFTD患者均存在广泛的认知障碍，但EOAD患者表现出严重的整体功能网络改变（平均节点强度、局部效率、聚类系数较低，路径长度较长），而bvFTD患者的整体脑功能结构相对保留。bvFTD患者额岛叶的节点强度降低，额岛叶和颞叶区域的功能连接发生相对局限性改变。后脑节点，特别是顶叶的功能连接中断，将EOAD患者与bvFTD患者区分开来。EOAD与半球内和半球间功能相关性的广泛丧失有关，而bvFTD则表现为半球内连接的优先破坏。
在EOAD和bvFTD患者中观察到了疾病特异性的功能网络拓扑和连接改变模式。图谱分析和连接组学可能有助于临床诊断，并有助于阐明神经退行性痴呆之间的病理生理差异。
