Moderate to severe traumatic brain injury (msTBI) can result in long-term cognitive, behavioral, and physical impairments that often persist for years or remain lifelong. Photobiomodulation (PBM), or near-infrared light therapy, targets underlying cellular dysfunction by improving mitochondrial function, adenosine triphosphate production, and circulation, offering a non-invasive therapeutic approach. We present a case report of a 56-year-old white male with severe TBI who completed a 12-week transcranial and intranasal PBM intervention approximately three years post-injury. Following intervention, differential tractography revealed significant reductions in restricted diffusion imaging (RDI), a marker suggestive of neuroinflammation, by an average of 13% across multiple white matter tracts, including those involved in language processing. The participant demonstrated improvement on a measure of verbal working memory and grip strength, though other objective cognitive testing showed variable results, likely influenced by persistent aphasia and alexia. Importantly, qualitative reports from both the participant and his spouse indicated meaningful improvements in daily functioning, including enhanced recall and verbal expression, improved autonomic functioning, better mood, and increased energy levels. These findings suggest PBM may facilitate continued recovery in the chronic phase of msTBI recovery by addressing cellular mechanisms, warranting further investigation through larger randomized controlled trials to establish efficacy and optimal treatment protocols.
McCabe et al. (Tue,) studied this question.