Structural consequences of diffuse traumatic brain injury: A large deformation tensor-based morphometry study

Abstract

Traumatic brain injury (TBI) is one of the most common causes of long-term disability. Despite the importance of identifying neuropathology in individuals with chronic TBI, methodological challenges posed at the stage of inter-subject image registration have hampered previous voxel-based MRI studies from providing a clear pattern of structural atrophy after TBI. We used a novel symmetric diffeomorphic image normalization method to conduct a tensor-based morphometry (TBM) study of TBI. The key advantage of this method is that it simultaneously estimates an optimal template brain and topology preserving deformations between this template and individual subject brains. Detailed patterns of atrophies are then revealed by statistically contrasting control and subject deformations to the template space. Participants were 29 survivors of TBI and 20 control subjects who were matched in terms of age, gender, education, and ethnicity. Localized volume losses were found most prominently in white matter regions and the subcortical nuclei including the thalamus, the midbrain, the corpus callosum, the mid-and posterior cingulate cortices, and the caudate. Significant voxel-wise volume loss clusters were also detected in the cerebellum and the frontal/ temporal neocortices. Volume enlargements were identified largely in ventricular regions. A similar pattern of results was observed in a subgroup analysis where we restricted our analysis to the 17 TBI participants who had no macroscopic focal lesions (total lesion volume> 1.5 cm 3 ). The current study confirms, extends, and partly challenges previous structural MRI studies in chronic TBI. By demonstrating that a large deformation image registration technique can be successfully combined with TBM to identify TBI-induced diffuse structural changes with greater precision, our approach is expected to increase the sensitivity of future studies examining brain-behavior relationships in the TBI population.

Long-term global and regional brain volume changes following severe traumatic brain injury: A longitudinal study with clinical correlates

“…The results of the present study are mainly in agreement with the findings of the single available TBM study on TBI (Kim et al, 2008). When comparing these two studies, one should bear in mind that while we investigated the regional distribution of late atrophy only, the study by Kim et al was not longitudinal and therefore did not distinguish between early and late atrophy.…”

“…Regional volume change is quantified by taking the Jacobian determinant at each voxel (Ashburner et al, 2000). One cross-sectional TBM study on TBI was very recently published (Kim et al, 2008). The population consisted of 29 patients with moderate to severe TBI, scanned once at least 3 months (ranging between 4 months and 27.5 years) following injury.…”

Cerebral Atrophy after Traumatic White Matter Injury: Correlation with Acute Neuroimaging and Outcome

“…Unlike conventional DWI, diffusion tensor imaging (DTI) characterizes the diffusion of water along white matter tracts. Our group and others are studying DTI in the hope that it would be more sensitive to axonal pathology after traumatic injury (Bazarian et al, 2007;Kim et al, 2008;Sidaros et al, 2008;Wang et al, 2008). DTI is able to visualize changes that were not seen on conventional scans and strongly correlated with functional outcome.…”

Strategy‐based reasoning training modulates cortical thickness and resting‐state functional connectivity in adults with chronic traumatic brain injury

“…MRI‐based morphometry has revealed altered cortical thickness and volume within individuals who have sustained a TBI (Bendlin et al., 2008; Gale, Baxter, Roundy, & Johnson, 2005; Kim et al., 2008; Sidaros et al., 2009; Spitz et al., 2013; Tate et al., 2014; Turken et al., 2009; Warner et al., 2010; Zhou et al., 2013). These altered cortical morphometric properties are frequently associated with functional deficits (Gale et al., 2005; Palacios et al., 2013; Sidaros et al., 2009; Spitz et al., 2013; Warner et al., 2010; Zhou et al., 2013), and correspondences between MRI‐based and histological morphometric data of TBI individuals have been reported (Maxwell, MacKinnon, Stewart, & Graham, 2009).…”