Loss of microstructural integrity in the limbic-subcortical networks for acute symptomatic traumatic brain injury

Area of Science:

• Neurology
• Neuroimaging
• Traumatic Brain Injury Research

Background:

• Previous mild traumatic brain injury (mTBI) research reported inconsistent white matter diffusivity findings.
• The Glasgow Coma Scale is unreliable for assessing TBI severity and often lacks documentation.
• The Mayo classification system offers a more refined approach to TBI severity, dividing mTBI into "probable and symptomatic" groups.

Purpose of the Study:

• To investigate microstructural integrity changes in symptomatic acute TBI (<1 week) using tract-based spatial statistics (TBSS).
• To identify specific brain regions affected by symptomatic TBI in the acute phase.

Main Methods:

• Utilized Magnetic Resonance Imaging (MRI) including conventional scans, Susceptibility-Weighted Imaging (SWI), and Diffusion Tensor Imaging (DTI).
• Employed the tract-based spatial statistics (TBSS) approach for analyzing white matter microstructural integrity.
• Included 12 patients with symptomatic acute TBI and 13 healthy volunteers.

Main Results:

• No visible lesions were detected in patients using conventional and SWI neuroimaging.
• Widespread reductions in fractional anisotropy (FA) were observed in both gray and white matter within the TBSS skeleton.
• Limbic-subcortical structures showed particularly notable declines in FA.
• Symptomatic TBI patients did not exhibit significant FA changes compared to healthy controls in this analysis.

Conclusions:

• Symptomatic acute TBI is associated with widespread white matter microstructural alterations, detectable via DTI-TBSS despite normal conventional/SWI imaging.
• Understanding these acute changes is crucial for comprehending neuroplasticity and degenerative processes post-TBI.
• Findings may inform future advancements in TBI management and intervention strategies.