Small World Properties Changes in Mild Traumatic Brain Injury (MTBI)

Yongxia Zhou¹, Yulin Ge¹, Yvonne W. Lui¹, Joseph Reaume¹, Robert I. Grossman¹

Small world properties such as betweenness centrality and clustering coefficient based on resting-state fMRI were used to evaluate global and local efficiency changes in 33 MTBI patients compared to 45 controls, and their changes were correlated with axonal injury by diffusion tensor imaging and postconcussive syndrome (PCS) in patients. We found reduced betweenness centrality and increased clustering coefficient in patients and these abnormalities correlated with white matter fractional anisotropy reductions and PCS. Our results suggest that disrupted global axonal integrity may cause decreased global efficiency of neuronal source utilization accompanying with local network upregulation as a compensatory mechanism in MTBI.