Hockey Concussion Education Project, Part 3. White matter microstructure in ice hockey players with a history of concussion: a diffusion tensor imaging study

Abstract

Object The aim of this study was to examine the brain’s white matter microstructure using magnetic resonance diffusion tensor imaging (DTI) in ice hockey players with a history of clinically symptomatic concussion compared to those players without a history of concussion. Methods Sixteen players with a history of concussion (Concussed Group; mean age: 21.7 ± 1.5 years; 6 female) and eighteen players without a history of concussion (Non-Concussed Group; mean age: 21.3 ± 1.8 years, 10 female) underwent 3T DTI at the end of the Canadian Interuniversity Sports ice hockey season 2011–2012. Tract-based spatial statistics (TBSS) was used to test for group differences in fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and trace. Cognitive evaluation was performed using the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) and the Sport Concussion Assessment Tool-2 (SCAT2). Results TBSS revealed a significant increase in FA and AD, and a significant decrease in RD and trace in several brain regions in the Concussed group, compared with the Non-concussed group (p < 0.05). The regions with increased FA and decreased RD and trace included the right posterior limb of the internal capsule, the right corona radiata, and the right temporal lobe. Increased AD was observed in a small area in the left corona radiata. DTI measures neither correlated with the ImPACT nor SCAT2. Conclusion The results of the current study indicate that a history of concussion may result in alterations of the brain’s white matter microstructure in ice hockey players. Increased FA based on decreased RD may reflect neuroinflammatory or neuroplastic processes of the brain responding to brain trauma. Future studies are needed that include a longitudinal analysis of the brain’s structure and function following a concussion in order to elucidate further the complex time course of DTI changes and their clinical meaning.

Mind the gaps—advancing research into short-term and long-term neuropsychological outcomes of youth sports-related concussions

“…53 Collegiate ice hockey players exhibited similar white matter changes over the course of a season. [54][55][56][57] In addition, repetitive subconcussive head impacts in collegiate American football players have been linked, in a dose-dependent manner, to deficits in BBB integrity, potential loss of white matter integrity, and cognitive dysfunction. 58 These findings probably reflect some level of risk for youths who sustain repetitive subconcussive head impacts, although little research has been devoted specifi cally to this topic.…”

Brain magnetic resonance imaging CO2 stress testing in adolescent postconcussion syndrome

“…Clinical neuroimaging studies, including conventional MRI, are normal in the majority of cases. 17 For this reason, authors of recent studies have aimed to apply even more sophisticated neuroimaging techniques to this condition, including magnetoencephalography, 53 diffusion tensor imaging (DTI), 11,25,29,31,44,47 and task-based functional MRI (fMRI). 7,26,35,49 Despite detecting changes between groups of concussion patients and healthy controls, none of these techniques has emerged as a useful clinical tool that contributes to the management of acute SRC or PCS.…”

White Matter Damage and Brain Network Alterations in Concussed Patients: A Review of Recent Diffusion Tensor Imaging and Resting-State Functional Connectivity Data

“…Whereas some recent studies have indicated a correlation between cognitive measures and functional [39,42,[48][49][50] or structural neuroimaging data [16,17,24,26,28], other studies have failed to do so [15,19,30].…”

“…Although the number of published studies using DTI has more than quadrupled since 2002 [12], the utility of DTI for assessing white matter tract injury in concussion is still unclear. Several recent DTI studies have reported either high [13][14][15][16][17][18][19] or low [18,[20][21][22][23][24][25][26] FA following concussion, and one longitudinal study has shown both increases as well as decreases of anisotropy within the same individual over time [18] (see Table 1). These disparate findings in the recent concussion literature have spurred the hypothesis that anisotropic differences in concussed patients could differ depending on whether the patient is imaged immediately after the concussion or months/years postconcussion [13,14].…”