Disrupted brain topological network and its association with clinical features in posterior cortical atrophy

The characteristics of structural brain topological network alterations and their correlation with clinical features in posterior cortical atrophy (PCA) remain elusive. This study aims to explore the structural topological network alterations and their correlation with clinical features in PCA. Thirty-four patients with PCA and 34 healthy controls were enrolled in this cross-sectional study and underwent diffusion tensor imaging, structural MRI and neuropsychological assessment. The graph theory method was applied to capture the individual structural properties of the network. Partial correlation analysis was conducted to investigate the clinical relevance of the network properties. The global metrics of the structural and topological network are altered in the PCA group. The nodal metrics were changed in the occipital, parietal, temporal and frontal lobes. Global network metrics are associated with cognition and disease severity. For the node associated with apraxia, finger agnosia, left-right disorientation and agnosia for colour, face and object, we observed a similar but not identical nodal distribution, which was mainly distributed in the parietal cortex. Notably, we observed frontal nodes, including the orbital gyrus, contribute to the left-right disorientation and colour agnosia, and the rectus contributes to the object agnosia. This study helps us understand the underlying mechanism of the symptom network in PCA and provides a promising biomarker for PCA.