Effect of Low-Level Light Therapy on brain metabolite in Patients with Moderate Traumatic Brain Injury

Motivation: Transcranial low-level near-infrared (NIR) light therapy (LLLT) has been emerging as a therapeutic intervention for traumatic brain injury (TBI). Goal(s): The goal of this study was to assess the metabolic responses to the administration of LLLT in patients with moderate TBI. Approach: We used serial 2D MR spectroscopic imaging to measure metabolite concentrations in TBI participants who were either treated with LLLT or with sham. Results: Sham-treated participants showed a significant increase in myo-inositol/N-acetyl aspartate (mI/NAA) in the corpus callosum 3 months post injury indicating lasting inflammation and neuronal injury, while LLLT treated participants' mI/NAA ratios remained unchanged. Impact: This longitudinal study suggests a neuroprotective effect of acute administration of LLLT using MRS on individuals with moderate TBI.