A Study of Lobar Atrophy and White Matter Tract Damage in Pediatric Patients with Traumatic Brain Injury (P3.261)

Objective: To investigate, in patients with pediatric severe and moderate traumatic brain injury (TBI), the presence and severity of white matter (WM) tract damage and cortical lobar atrophy and their correlation with disease clinical scales. Background: Pediatric TBI is a WM disconnection syndrome due to damage to long-cortico-cortical pathways. The role of WM tract disruption and brain atrophy has not yet been fully characterized. Methods: Diffusion Tensor (DT) and 3D T1-weighted MRI scans were obtained using a 3 tesla scanner from 22 children with severe and moderate TBI and 31 age-matched healthy children. Patients were tested with functional scales and the Wechsler Intelligence Scale for Children (WISC). DT MRI indexes were obtained from the arcuate (AF), inferior longitudinal (ILF), uncinate (UF) and inferior fronto-occipital (IFO) fasciculi, the cerebellar peduncles (CP) and corpus callosum (CC). Whole brain and lobar volumes (using masks from Harvard-Oxford cortical atlas) were measured. Comparisons between patients and controls, and between patients in acute (<6 months from the event) vs chronic (>6 months) conditions were performed (False Discovery Rate correction). Results: Except for pre- and postcentral gyri and occipital lobe volume, all DT MRI indices and atrophy measures were abnormal in patients compared to healthy controls. Compared to acute, chronic patients had more severe atrophy of temporal lobe and more severe DT MRI abnormalities of CC, ILF, UF and inferior CP. In TBI patients, significant correlations were found between: 1) temporal lobe atrophy vs DT MRI abnormalities in several WM tracts; 2) whole brain atrophy vs WISC performance. Conclusions:TBI in children is characterized by a widespread WM and lobar damage. In the chronic stage, higher susceptibility to tissue loss is detected in the temporal lobe. Supported by a grant from the Ministry of Health Research, Ricerca Corrente 2010-2012, Scientific Institute “E. Medea.”