Diffusion tensor
imaging of sports-related concussion in adolescents

N., Borich MR., Makan N., Moore T., Frew K., Emery CA., Boyd LA. Pediatric
Neurology. 2013; 48: 24-29.

impact that a concussion has on an immature adolescent brain is largely
unknown. Magnetic resonance imaging advancements such as diffusion tensor imaging may
help us understand these changes because it provides quantitative measure of
the subtle changes within the white matter tissue in the
brain following a concussion. Therefore, the purpose of this study was to use
diffusion tensor imaging to investigate the short-term structural differences
between 12 adolescents that had sustained a recent concussion (within 2 months)
and 10 adolescent athletes with no concussion history. Additionally, the association
of diffusion tensor imaging measures and the Sports Concussion Assessment Tool 2 (SCAT2) was assessed. The authors found that the
integrity of the white matter  differed between the
concussed and non-concussed groups.  Furthermore,
the SCAT2 was associated with two measures of white matter integrity.  However, there was no difference in SCAT2
scores between groups.

concussion is defined as a pathophysiological process that is induced by
traumatic biomechanical forces. Thus, when a neuron is stretched many cellular
changes take place (known as the neurometabolic cascade; Hovda & Giza). These changes are very subtle and most imaging
techniques cannot detect them.  These
researchers provide preliminary evidence that brains exposed to a recent
concussion have differences in the integrity of the white matter compared to
healthy brains that can be observed with diffusion tensor imaging. The observed
changes in the white matter may be caused by mechanical forces from the
concussion that stretch neurons in the white matter and cause ion channels to
open. This could lead to an increase in intracellular water and decrease in
extracellular water, which may be one reason there is decreased diffusivity.
These observed changes could also be associated with the tissue injury itself
that induces inflammation.  There are
several limitations to this study that should be noted. Firstly, the sample
size is small, which limits our ability to apply these results to our clinical
populations. In addition, there were a varying number of concussions (from 1 to
4 concussions) within the concussed group. Also, there was a varying time for
the concussed group to get there diffusion tensor imaging (up to 2 months post
injury). These variables could have altered the outcome of their data. This preliminary
research will hopefully inspire future research to determine if diffusion
tensor imaging has a role in diagnosing concussions, monitoring recovery, and
return-to-play decisions. Do you think magnetic resonance imaging, like
diffusion tensor imaging, would be a helpful diagnostic tool for concussions?

by: Jane McDevitt MS, ATC, CSCS
by: Jeffrey Driban


Virji-Babul N, Borich MR, Makan N, Moore T, Frew K, Emery CA, & Boyd LA (2013). Diffusion tensor imaging of sports-related concussion in adolescents. Pediatric Neurology, 48 (1), 24-9 PMID: 23290016