Clinical utility of diffusion tensor imaging in sport-related concussion: a systematic review.

Objective: Sport-related concussion (SRC) is a prevalent form of traumatic brain injury that is associated with long-term neurological and psychiatric impairment, particularly among athletes with a history of repetitive concussions. The biological variability of SRC's impact on the brain, as well as a lack of objective biomarkers to diagnose and prognosticate concussion, has prompted interest in advanced neuroimaging methods such as diffusion tensor imaging (DTI). By measuring disruptions in water diffusivity due to head trauma, DTI can detect alterations in white matter integrity that are not visualized by conventional imaging methods. This systematic review aims to synthesize major trends and findings on original research studies that utilized DTI to evaluate subjects for SRC. Methods: An initial search from PubMed, Web of Science, and Scopus generated 397 articles published from database inception to 2024, with 26 studies included in the final qualitative synthesis. Results: Findings showed heterogenous changes in DTI parameters during acute injury with more consistent alterations seen in chronic injury, particularly as reduced fractional anisotropy and elevated mean diffusivity. Significant variability was observed in study design and methodology, which may explain discrepancies in findings across studies. Conclusions: Future research efforts should implement standardized methods capable of accounting for inter-individual differences to further validate DTI's role as an objective biomarker of SRC. Advances in knowledge: Individualized analysis of DTI could serve as a diagnostic tool and prognostic metric for patients with SRC, thus enabling an objective measure of long-term outcome and suitability for return-to-play.