Early Cortical Thickness Change after Mild Traumatic Brain Injury following Motor Vehicle Collision

Abstract

In a motor vehicle collision (MVC), survivors often receive mild traumatic brain injuries (mTBI). Although there have been some reports of early white matter changes after an mTBI, much less is known about early cortical structural changes. To investigate early cortical changes within a few days after an MVC, we compared cortical thickness of mTBI survivors with nonmTBI survivors, then reexamined cortical thickness in the same survivors 3 months later. MVC survivors were categorized as mTBI or non-mTBI based on concussive symptoms documented in emergency departments (EDs). Cortical thickness was measured from MRI images using FreeSurfer within a few days and again at 3 months after MVC. Post-traumatic stress symptoms and physical conditions were also assessed. Compared with the non-mTBI group (n = 23), the mTBI group (n = 21) had thicker cortex in the left rostral middle frontal (rMFG) and right precuneus gyri, but thinner cortex in the left posterior middle temporal gyrus at 7.2 -3.1 days after MVC. After 3 months, cortical thickness had decreased in left rMFG in the mTBI group but not in the non-mTBI group. The cortical thickness of the right precuneus region in the initial scans was positively correlated with acute traumatic stress symptoms for all survivors and with the number of reduced activity days for mTBI survivors who completed the follow-up. The preliminary results suggest that alterations in cortical thickness may occur at an early stage of mTBI and that frontal cortex structure may change dynamically over the initial 3 months after mTBI.

Cortical Thickness in Mild Traumatic Brain Injury

“…11 Their study found cortical thinning in the left middle temporal gyrus at baseline, but much less extensive than what was observed in the current study. In addition, their study reported significant cortical thickening in the mTBI group in the right precuneus and the left rostral middle frontal gyrus.…”

“…10 Another recent study, based on 21 patients with mTBI from motor vehicle collisions, found cortical thinning in the left posterior middle temporal gyrus and cortical thickening in the right precuneus and left rostral middle frontal gyrus in the acute phase after injury. 11 In light of these findings, changes in cortical thickness appear to be a pathologic feature in mTBI.…”

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

“…In a pilot study, Wang et al [27] observed alterations in cortical thickness at an early stage after MTBI. Thus, the frontal cortical structures may change dynamically over the initial 3 months after injury.…”

“…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].…”