To investigate functional brain network architecture in patients with posterior cortical atrophy (PCA), within atrophic and hypometabolic regions, and according with CSF AD profile.

  Multimodal imaging approaches have been gaining momentum in neuroscience due to the increasing availability of different imaging datasets and, most importantly, to the need of new tools to define more reliable biomarkers. In the present study, for the first time, we will combine non-redundant brain imaging and biologic data in patients affected by a PCA (n=18).

The human macroscale connectome was constructed from resting-state functional MRI. Graph analysis and connectomics assessed topological network properties, regional functional connectivity, and intra- and inter-hemispheric between-lobe connectivity, also within hypometabolic and atrophic nodes, and according to the CSF AD profile. Atrophic and hypometabolic regions were identified by voxel based morphometry on 3D T1-weighted MRI and FDG-PET analyses, respectively. PCA were classified with typical CSF AD (PCA-tAD; abnormal amyloid, T-tau, P-tau), atypical AD CSF (PCA-aAD; abnormal amyloid only), or non-AD CSF (PCA-nonAD) profile. Fifty-nine age- and sex- matched controls were enrolled.

Present multimodal neuroimaging approach showed the distant functional effects of the atrophy and hypometabolism occurring in the posterior brain regions on preserved anterior brain areas. PCA patients with both abnormal CSF amyloid and T-Tau/P-tau show more severe connectome alterations, maybe suggesting a more aggressive progression.