Multi modal neuroimaging: Diffusion Tensor Imaging, MR Spectroscopy and Susceptibility weighted Imaging in association with clinical measures to assess sports-related concussion in varsity level college athletes

Principle Investigator: Osherson D., PhD

Institution: Princeton University

Title: Multimodal neuroimaging: Diffusion Tensor Imaging, MR Spectroscopy and Susceptibility weighted Imaging in association with clinical measures to assess sports-related concussion in varsity level college athletes.

Abstract: Each year, an estimated 1.5 million Americans sustain TBI (Thurman et al., 1998). A study by the Centers for Disease Control and Prevention estimated that 300,000 sports-related concussions occur annually in the United States (Thurman et al., 1998). Appropriate timing of an athlete’s return-to-play is of particular importance as the evidence of serious long-term effects of recurrent concussions is growing. Cumulative cognitive effects have been documented by Gronwall (1975) and Guskiewicz (2003, 2005, 2007). As of now, all studies of concussed individuals demonstrating either structural or functional alterations in the brain have been based on between group differences using healthy control athletes. These studies are thus unable to distinguish the effects on brain structure and metabolism as a result of old injuries as compared to the effects of the most recent concussion.

Aims: Here we propose a longitudinal study of varsity athletes who participate in a baseline scanning protocol and subsequently sustain a sports-related concussion; this will provide reliable identification of the specific neurological effects of current injury. We will assess structural and neurometabolic changes in the white matter during the early phase of recovery, and determine how such observations can be used to predict long-term outcomes in sports-related concussion (including the context of previous injury).

Study Design: Princeton University varsity football and ice hockey players will be enrolled (approximately 100 subjects) in the study. The same imaging protocol will be used for

  1. the baseline scan of all 100 subjects,
  2. on all athletes who sustain a concussion within 72 hours,
  3. at two weeks, and
  4. at two months post-injury.

Materials and Methods: Subjects will be scanned on a Siemens Skyra 3T scanner at the imaging facility of the Princeton Neuroscience Institute, imaging protocol will consist of: Susceptibility Weighted Imaging (SWI), diffusion tensor imaging (DTI) and Magnetic Resonance Spectroscopy (MRS). All volunteers will have completed the standard baseline testing as required by the Department of Athletic Medicine Services at Princeton University, which includes the ImPACT and SCAT II test. Immediately after injury, concussed athletes will be evaluated by the team physician and a SCAT II will be administered on the sideline. The entire MP testing protocol (ImPACT, paper/pencil, PHQ-9 and GAD-7) will be administered within 72 hours, at two weeks after injury, and two months later.

Main Outcome Measures: Number of micro hemorrhages (SWI), mean diffusivity (DTI), fractional anisotropy (DTI), NAA/cholin, NAA/creatin and creatin/cholin concentrations (MRS), and NP test results (ImPACT scores, SCAT II, and paper/pencil test scores).

Significance: The proposed study will provide a comprehensive longitudinal assessment of structural, neurometabolic and hemorrhagic changes in the brain after concussion and assess how neurobiological correlates of recovery relate to behavior. Ultimately, results of this study would lay the groundwork for a more objective measure of mild traumatic brain injury, and allow the assessment of remedial procedures.