Beyond variability: Unveiling brain connectivity alterations in frontotemporal dementia

LUCAS SEDEÑO; SOFÍA ABREVAYA; LAURA DE LA FUENTE; SOL FITTIPALDI; SANDRA BÁEZ; AGUSTIN IBÁÑEZ; ADOLFO M. GARCÍA; INDIRA GARCÍA-CORDERO; TERESA TORRALVA

Habana

Congreso; 18th IOP World Congress; 2016

We explored, across different countries and recording parameters, whether graph-theory ?a sensitive functional connectivity framework?could consistently distinguish behavioral-variant frontotemporal dementia (bvFTD) patients from controls. Then, to evaluate the specificity of network alterations in bvFTD, we assessed other neurological conditions. We enrolled 139 participants. These included 45 bvFTD patients and 60 controls from three international clinics, and three additional patient groups: fronto-insular stroke (FIS), Alzheimer?s disease (AD), and primary progressive aphasia (PPA). All participants underwent resting-state fMRI recordings with different scanners and acquisition parameters. We focused our analysis on graph metrics of network integration, segregation, and centrality. Graph metrics of bvFTD patients compared to controls consistently revealed: (1) inefficient information transfer between intra-regional and distributed brain areas, and (2) aberrant centrality features of frontotemporal regions. These patterns were homogeneous across countries. Also, bvFTD differed from FIS in overall network measures. Differences between bvFTD and both AD and PPA concerned anatomically distinct alterations of network centrality. This is the first multicenter report exploring FC patterns via graph-theory in bvFTD. Our approach was robust enough to discriminate bvFTD patients from both healthy controls and other neurological samples across centers. The consistency of these findings across highly heterogeneous measurement contexts highlights graph-theory as a potential gold-standard approach for brain network analysis in bvFTD.