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White matter alterations in college football players: a longitudinal diffusion tensor imaging study

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Abstract

The aim of this study was to evaluate longitudinal changes in the diffusion characteristics of brain white matter (WM) in collegiate athletes at three time points: prior to the start of the football season (T1), after one season of football (T2), followed by six months of no-contact rest (T3). Fifteen male collegiate football players and 5 male non-athlete student controls underwent diffusion MR imaging and computerized cognitive testing at all three timepoints. Whole-brain tract-based spatial statistics (TBSS) were used to compare fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD), and trace between all timepoints. Average diffusion values were obtained from statistically significant clusters for each individual. No athlete suffered a concussion during the study period. After one season of play (T1 to T2), we observed a significant increase in trace in a cluster located in the brainstem and left temporal lobe, and a significant increase in FA in the left parietal lobe. After six months of no-contact rest (T2 to T3), there was a significant decrease in trace and FA in clusters that were partially overlapping or in close proximity with the initial clusters (T1 to T2), with no significant changes from T1 to T3. Repetitive head impacts (RHI) sustained during a single football season may result in alterations of the brain’s WM in collegiate football players. These changes appear to return to baseline after 6 months of no-contact rest, suggesting remission of WM alterations. Our preliminary results suggest that collegiate football players might benefit from periods without exposure to RHI.

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Acknowledgements

Inga Koerte was supported by the Else Kröner-Fresenius Stiftung, Germany. Michael Mayinger was supported by the Petraeic Legate Foundation. This work was part of the doctoral thesis of Michael Mayinger. This study was supported by funds from the National Football League Charities.

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Correspondence to Inga Katharina Koerte.

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This study was funded in part by the National Football League Charities.

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Author Mayinger declares that he has no conflict of interest. Author Merchant-Borna declares that he has no conflict of interest. Author Hufschmidt declares that he has no conflict of interest. Author Muehlmann declares that he has no conflict of interest. Author Weir declares that she has no conflict of interest. Author Rauchmann declares that he has no conflict of interest. Author Shenton declares that she has no conflict of interest. Author Koerte declares that she has no conflict of interest. Author Bazarian declares that he has no conflict of interest.

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All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

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Michael Christian Mayinger and Kian Merchant-Borna are Co-first authors.

Inga Katharina Koerte and Jeffrey John Bazarian are Co-senior authors.

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Mayinger, M.C., Merchant-Borna, K., Hufschmidt, J. et al. White matter alterations in college football players: a longitudinal diffusion tensor imaging study. Brain Imaging and Behavior 12, 44–53 (2018). https://doi.org/10.1007/s11682-017-9672-4

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