Fronto‐temporal vulnerability to disconnection in paediatric moderate and severe traumatic brain injury

Abstract

Background In patients with moderate and severe paediatric traumatic brain injury (TBI), we investigated the presence and severity of white matter (WM) tract damage, cortical lobar and deep grey matter (GM) atrophies, their interplay and their correlation with outcome rating scales. Methods Diffusion tensor (DT) and 3D T1‐weighted MRI scans were obtained from 22 TBI children (13 boys; mean age at insult = 11.6 years; 72.7% in chronic condition) and 31 age‐matched healthy children. Patients were tested with outcome rating scales and the Wechsler Intelligence Scale for Children (WISC). DT MRI indices were obtained from several supra‐ and infra‐tentorial WM tracts. Cortical lobar and deep GM volumes were derived. Comparisons between patients and controls, and between patients in acute (<6 months from the event) vs. chronic (≥6 months) condition were performed. Results Patients showed a widespread pattern of decreased WM FA and GM atrophy. Compared to acute, chronic patients showed severer atrophy in the right frontal lobe and reduced FA in the left inferior longitudinal fasciculus and corpus callosum (CC). Decreased axial diffusivity was observed in acute patients versus controls in the inferior fronto‐occipital fasciculus and CC. Chronic patients showed increased axial diffusivity in the same structures. Uncinate fasciculus DT MRI abnormalities correlated with atrophy in the frontal and temporal lobes. Hippocampal atrophy correlated with reduced WISC scores, whereas putamen atrophy correlated with lower functional independence measure scores. Conclusions The study isolated a distributed fronto‐temporal network of structures particularly vulnerable to axonal damage and atrophy that may contribute to cognitive deficits following TBI.

Topological Aberrance of Structural Brain Network Provides Quantitative Substrates of Post-Traumatic Brain Injury Attention Deficits in Children

“…This result of reduced topological modularity of the structural subnetwork in parietal regions is consistent with findings from a previous structural network study using deterministic tractography (Caeyenberghs et al, 2012). In addition, several previous DTI studies in children with chronic TBI have consistently reported significantly decreased FA of the superior longitudinal fasciculus, which is a major association tract that connects parietal lobe with frontal lobe (Ewing-Cobbs et al, 2016;Konigs et al, 2018;Molteni et al, 2019). An early structural MRI study reported significantly reduced cortical thickness of bilateral supramarginal gyri in children with chronic TBI children, relative to matched controls (Merkley et al, 2008); while a more recent longitudinal study reported significant associations between greater volume of left supramarginal gyrus and worse overall cognitive performance (Dennis et al, 2016).…”

White Matter Disruption in Pediatric Traumatic Brain Injury

“…1,2 Numerous dMRI studies have demonstrated that young patients with traumatic brain injury (TBI) show abnormal WM organization in several fiber tracts such as the corpus callosum (CC). 3-11 These studies have also reported significant, moderate to high correlations between symptoms and decreased WM organization such that increased severity of WM disruption predicts poorer behavioral performance in young patients with TBI. 12,13 The plasticity of the human brain during development supports learning and adaptation, but its hidden cost may be increased vulnerability to injury.…”

White Matter Disruption in Pediatric Traumatic Brain Injury: Results from ENIGMA Pediatric msTBI

“…Advanced magnetic resonance imaging (MRI) techniques have shown great promise in furthering our understanding of the injury and recovery processes that occur during dynamic periods of neurodevelopment (Dennis et al , 2018, Lindsey et al , 2019 . Research using diffusion MRI (dMRI) has revealed widespread disruption of brain microstructure in children and adolescents with moderate/severe TBI (msTBI) (Wozniak et al , 2007;Yuan et al , 2007;Levin et al , 2008;Caeyenberghs et al , 2009Caeyenberghs et al , , 2010Caeyenberghs et al , , 2012Oni et al , 2010;Wilde et al , 2010Wilde et al , , 2012Wu et al , 2010;McCauley et al , 2011;Treble et al , 2013a , b , 2017Johnson et al , 2015;Ewing-Cobbs et al , 2016;Faber et al , 2016;Genc et al , 2017;Königs et al , 2018, Lindsey et al , 2019Molteni et al , 2019;Watson et al , 2019) , which is less likely to be detected by conventional clinical neuroimaging. DMRI can model white matter (WM) tracts and assess tissue structure by mapping the diffusion of water molecules; it is particularly sensitive to traumatic axonal injury, a hallmark of msTBI (Ashwal et al , 2014, Dennis et al , 2017 .…”