Differences in Regional Brain Volumes Two Months and One Year after Mild Traumatic Brain Injury

Abstract

Conventional structural imaging is often normal after mild traumatic brain injury (mTBI). There is a need for structural neuroimaging biomarkers that facilitate detection of milder injuries, allow recovery trajectory monitoring, and identify those at risk for poor functional outcome and disability. We present a novel approach to quantifying volumes of candidate brain regions at risk for injury. Compared to controls, patients with mTBI had significantly smaller volumes in several regions including the caudate, putamen, and thalamus when assessed 2 months after injury. These differences persisted but were reduced in magnitude 1 year after injury, suggesting the possibility of normalization over time in the affected regions. More pronounced differences, however, were found in the amygdala and hippocampus, suggesting the possibility of regionally specific responses to injury.

Longitudinal changes in brain morphology from 4 weeks to 12 months after mild traumatic brain injury: Associations with cognitive functions and clinical variables

“…This is in line with Zagorchev who observed reductions in subcortical structures, including the caudate nucleus [26]. Mounting evidence indicates that the caudate nucleus plays an important role in processing information and relays this information back to distinct cortical regions.…”

“…Some longitudinal studies have described the development of atrophy after MTBI [23][24][25][26][27][28]. In contrast, two other studies observed no atrophy in patients diagnosed with MTBI [16,21].…”

“…However, few MTBI studies have investigated atrophy [21][22][23][24][25][26][27][28] and even fewer have investigated the associations between amount of atrophy and post-concussive symptoms, functional outcome and neuropsychological functioning. A recent study demonstrated significant volume decreases one year after a single concussive episode in the bilateral anterior cingulate white matter, left cingulate gyrus isthmus white matter and right precuneal gray matter [25].…”

Thalamic Functional Connectivity in Mild Traumatic Brain Injury: Longitudinal Associations With Patient-Reported Outcomes and Neuropsychological Tests

“…5–9 The thalamus functions as a sensory relay center with projections to multiple cortical regions. 10 Prior studies show the thalamus is susceptible to injury and can result in decreased volume, 11, 12 inflammation, 13 and reduced perfusion. 14 Early magnetic resonance imaging (MRI) studies using fractional anisotropy found associations between the thalamus and TBI symptoms.…”

A Multi-resolution T-Mixture Model Approach to Robust Group-Wise Alignment of Shapes

“…Two clinical data sets were used for validation: (1) a 2D set of 100 femur boundaries segmented automatically using a clinically employed software (Hologic Apex 3.2) from dual-energy X-ray absorptiometry images of healthy subjects; (2) a 3D set of 30 caudate nuclei, segmented automatically [10] from T1-weighted MR images 1 of healthy subjects. Point sets were generated from these segmentations using a marching cubes-based surface extraction algorithm.…”