Chronic Traumatic Encephalopathy Neuropathologic Change is Infrequent Following Isolated Moderate-Severe Traumatic...

Area of Science:

• Neuropathology
• Neurotrauma
• Brain Injury Research

Background:

• Chronic traumatic encephalopathy-neuropathologic change (CTE-NC) is primarily linked to repetitive head impacts (RHI) in athletes.
• The association between CTE-NC and isolated traumatic brain injury (TBI) remains less understood.

Purpose of the Study:

• To systematically review an autopsied cohort with a history of TBI, including isolated TBI and RHI, for CTE-NC.
• To explore the neuropathologic features of CTE-NC in individuals with varied head impact histories.

Main Methods:

• Comprehensive neuropathologic evaluation of 44 autopsied brains from the Late Effects of TBI (LETBI) cohort.
• Ex vivo neuroimaging to guide histological sampling of subtle neuropathologies.
• Assessment for tau-immunopositive pathology meeting CTE-NC criteria.

Main Results:

• Six cases (13.6%) exhibited CTE-NC, with tau pathology in perivascular arrangements.
• Five of six CTE-NC cases had significant RHI exposure; one case had CTE-NC after two isolated severe TBIs.
• Macroscopic and microscopic findings included volume loss, microvascular lesions, and tau accumulation.

Conclusions:

• CTE-NC is infrequent in individuals with isolated TBI, with most cases associated with RHI.
• Severe TBI may be a risk factor for CTE-NC in the absence of RHI.
• Co-occurrence of CTE-NC with other neurodegenerative pathologies was observed.