Table 6

Volume of white matter (WM) regions with significant pre-season to post-season change in MD, AD or RD in different WM tracts and the correlation between the diffusion tensor imaging change within significant regions with the total number of head impacts experienced during the season in the 22 participants in the non-collar group who underwent both pre-season and post-season MRI scans

WM tractsVolumeCorrelation coefficient r (p)
Region 01ATR, left1158−0.326 (ns)0.521 (0.013)0.474 (0.026)0.446 (0.038)
Region 02ATR, right836−0.181 (ns)0.349 (ns)0.255 (ns)0.315 (ns)
Region 03CST, left10050.073 (ns)0.240 (ns)0.178 (ns)0.171 (ns)
Region 04CST, right626−0.061 (ns)0.247 (ns)0.192 (ns)0.233 (ns)
Region 05Cingulum (CG part), left451−0.106 (ns)0.311 (ns)0.264 (ns)0.357 (ns)
Region 06Cingulum (CG part), right2210.039 (ns)0.375 (ns)0.304 (ns)0.373 (0.087)
Region 07Cingulum (HC part), left22−0.584 (0.004)0.526 (0.012)0.045 (ns)0.060 (ns)
Region 08Cingulum (HC part), right170.118 (ns)0.147 (ns)0.145 (ns)−0.053 (ns)
Region 09Forceps major417−0.321 (ns)0.354 (ns)0.241 (ns)0.453 (0.034)
Region 10Forceps minor2349−0.425 (0.049)0.479 (0.024)0.372 (ns)0.477 (0.025)
Region 11IFOF, left1053−0.328 (ns)0.498 (0.018)0.408 (0.059)0.516 (0.014)
Region 12IFOF, right10110.126 (ns)0.270 (ns)0.294 (ns)0.120 (ns)
Region 13ILF, left545−0.164 (ns)0.445 (0.038)0.216 (ns)0.396 (0.068)
Region 14ILF, right15−0.062 (ns)0.311 (ns)0.293 (ns)0.232 (ns)
Region 15SLF, left3022−0.210 (ns)0.371 (0.090)0.402 (0.064)0.364 (0.096)
Region 16SLF, right325−0.241 (ns)0.264 (ns)0.282 (ns)0.330 (ns)
Region 17UF, left601−0.449 (0.036)0.473 (0.026)0.299 (ns)0.542 (0.009)
Region 18UF, right1370.054 (ns)0.189 (ns)0.222 (ns)0.099 (ns)
Region 19SLF (temporal), left300.367 (ns)0.130 (ns)0.177 (ns)0.142 (ns)
Region 20SLF (temporal), right4−0.025 (ns)0.141 (ns)0.055 (ns)0.154 (ns)
  • The WM tracts were determined using WM atlas based on John Hopkins University’s ICBM WM tract probability map. The statistical significance derived from the correlation analyses were not corrected for multiple comparisons.

  • AD, axial diffusivity; ATR, anterior thalamic radiation; CG, cingulate gyrus; CST, corticospinal tract; FA, fractional anisotropy; HC, hippocampal; IFOF, inferior fronto-occipital fasciculus; ILF, inferior longitudinal fasciculus; MD, mean diffusivity; ns, not significant; RD, radial diffusivity; SLF, superior longitudinal fasciculus; UF, uncinate fasciculus.