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

Department of Neurology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9036, USA.
Journal of Neurotrauma (Impact Factor: 3.71). 12/2008; 25(12):1433-40. DOI: 10.1089/neu.2008.0683
Source: PubMed


Traumatic brain injury (TBI) is a pathologically heterogeneous disease, including injury to both neuronal cell bodies and axonal processes. Global atrophy of both gray and white matter is common after TBI. This study was designed to determine the relationship between neuroimaging markers of acute diffuse axonal injury (DAI) and cerebral atrophy months later. We performed high-resolution magnetic resonance imaging (MRI) at 3 Tesla (T) in 20 patients who suffered non-penetrating TBI, during the acute (within 1 month after the injury) and chronic stage (at least 6 months after the injury). Volume of abnormal fluid-attenuated inversion-recovery (FLAIR) signal seen in white matter in both acute and follow-up scans was quantified. White and gray matter volumes were also quantified. Functional outcome was measured using the Functional Status Examination (FSE) at the time of the chronic scan. Change in brain volumes, including whole brain volume (WBV), white matter volume (WMV), and gray matter volume (GMV), correlates significantly with acute DAI volume (r = -0.69, -0.59, -0.58, respectively; p <0.01 for all). Volume of acute FLAIR hyperintensities correlates with volume of decreased FLAIR signal in the follow-up scans (r = -0.86, p < 0.001). FSE performance correlates with acute hyperintensity volume and chronic cerebral atrophy (r = 0.53, p = 0.02; r = -0.45, p = 0.03, respectively). Acute axonal lesions measured by FLAIR imaging are strongly predictive of post-traumatic cerebral atrophy. Our findings suggest that axonal pathology measured as white matter lesions following TBI can be identified using MRI, and may be a useful measure for DAI-directed therapies.

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    • "To date, there do not appear to be studies examining white matter hyperintensities (WMH) or other T2-w/FLAIR abnormalities in military and/or Veteran cohorts. Anecdotally, WMH are commonly observed in Service Member and/or Veteran participants with mTBI, and examination of these findings may yield additional information as studies in civilian TBI populations have demonstrated modest relationships between WMH volume and clinical outcomes including TBI severity (Bigler et al. 2013), functional outcomes (Marquez de la Plata et al. 2007), and atrophic changes (Ding et al. 2008). Currently, there also appear to be no studies specifically examining SWI abnormalities in military or Veteran populations . "
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    • "The brainstem is notoriously involved in mTBI (Tomlinson 1970, Ommaya and Gennarelli 1974, Gennarelli 1986) but changes in other areas of the brain are also found. Overall reduction in white matter volume has been reported in association with mTBI (Ding et al. 2008, Levine et al. 2008, Schonberger et al. 2009), as well as white matter volume reduction at the level of the mesencephalon (midbrain) and the corona radiata (Holli et al. 2010). The corpus callosum (CC) also seems to be microdamaged in mTBI: Gale and Johnson (2005) showed a decreased CC volume in 36 patients with mTBI, which correlated with neuropsychological tests of motor function. "
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