Abstract
BACKGROUND AND PURPOSE: The effect of exposing the developing brain of a high school football player to subconcussive impacts during a single season is unknown. The purpose of this pilot study was to use diffusion tensor imaging to assess white matter changes during a single high school football season, and to correlate these changes with impacts measured by helmet accelerometer data and neurocognitive test scores collected during the same period.
MATERIALS AND METHODS: Seventeen male athletes (mean age, 16 ± 0.73 years) underwent MR imaging before and after the season. Changes in fractional anisotropy across the white matter skeleton were assessed with Tract-Based Spatial Statistics and ROI analysis.
RESULTS: The mean number of impacts over a 10-g threshold sustained was 414 ± 291. Voxelwise analysis failed to show significant changes in fractional anisotropy across the season or a correlation with impact frequency, after correcting for multiple comparisons. ROI analysis showed significant (P < .05, corrected) decreases in fractional anisotropy in the fornix-stria terminalis and cingulum hippocampus, which were related to impact frequency. The effects were strongest in the fornix-stria terminalis, where decreases in fractional anisotropy correlated with worsening visual memory.
CONCLUSIONS: Our findings suggest that subclinical neurotrauma related to participation in American football may result in white matter injury and that alterations in white matter tracts within the limbic system may be detectable after only 1 season of play at the high school level.
ABBREVIATIONS:
- CTE
- chronic traumatic encephalopathy
- FA
- fractional anisotropy
- FXST
- fornix-stria terminalis
- TBSS
- Tract-Based Spatial Statistics
Footnotes
Disclosures: Michael D. Clark—RELATED: Grant: National Institute of Neurological Disorders and Stroke, Comments: grant No. F30NS090816.* *Money paid to the institution.
This work was supported by Department Seed Funding, Department of Radiology, Duke University, Durham, North Carolina, and the National Institutes of Health under the Ruth L. Kirschstein National Research Service Award F30NS090816 from the National Institute of Neurological Disorders and Stroke.
Paper previously presented, in part, as a scientific poster at: Annual Meeting of the Radiological Society of North America, November 30–December 5, 2014; Chicago, Illinois.
- © 2018 by American Journal of Neuroradiology
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