Voxel-Based Analysis of Diffusion Tensor Imaging in Mild Traumatic Brain Injury in Adolescents

TLDR

Diffusion tensor imaging of normal‑appearing white matter in mild traumatic brain injury can reveal regional abnormalities linked to post‑concussion symptoms. The study aimed to test whether frontotemporal white‑matter changes are associated with post‑concussion symptoms and emotional disturbances in adolescents. Voxel‑based DTI was performed on 10 adolescents with acute mTBI and 10 controls 1–6 days post‑injury, followed by linear regressions linking apparent diffusion coefficient values to PCS severity and BSI emotional scores. Acute mTBI produced significant ADC reductions, decreased radial diffusivity, increased fractional anisotropy in multiple white‑matter regions—including the left thalamus—consistent with axonal cytotoxic edema and correlating with post‑concussion symptoms.

Abstract

<h3>BACKGROUND AND PURPOSE:</h3> DTI of normal-appearing WM as evaluated by conventional MR imaging in mTBI has the potential to identify important regional abnormalities that relate to PCS. VBA was used to examine WM changes in acute mTBI. <h3>MATERIALS AND METHODS:</h3> WM was assessed between 1 and 6 days postinjury with voxel-based DTI analyses in 10 adolescent patients with mTBI and 10 age-matched control participants. In addition to the voxel-based group, analysis used to identify brain pathology across all patients with mTBI, 2 voxel-based linear regressions were performed. These analyses investigated the relation between 1) the ADC and PCS severity scores, and 2) ADC and scores on the BSI of emotional symptoms associated with mTBI. We hypothesized that frontotemporal WM changes would relate to symptoms associated with PCS and endorsed on the BSI. <h3>RESULTS:</h3> Patients with mTBI demonstrated significant reductions in ADC in several WM regions and in the left thalamus. As expected, no increases in ADC were found in any region of interest. All injury-affected regions showed decreased radial diffusivity, unchanged AD, and increased FA, which is consistent with axonal cytotoxic edema, reflective of acute injury. <h3>CONCLUSIONS:</h3> Whole-brain WM DTI measures can detect abnormalities in acute mTBI associated with PCS symptoms in adolescents.