Increased Diffusion in the Brain of Professional Boxers: A Preclinical Sign of Traumatic

head blows that may cause brain injuries. Diffusion-weighted imaging is sensitive to micro-scopic changes and may be a useful tool to quantify the microstructural integrity of the brain. In this study, we sought to quantify microscopic alterations associated with chronic traumatic brain injury in professional boxers. METHODS: MR and diffusion-weighted imaging were performed in 24 boxers and in 14 age-and sex-matched control subjects with no history of head trauma. Using distribution analysis, the average diffusion constant of the entire brain (BDav) and diffusion distribution width () were calculated for each subject; findings in professional boxers were compared with those of control subjects. In the boxer group, correlations between diffusion changes and boxing history and diffusion changes and MR imaging findings were assessed. RESULTS: The measured diffusion values in the boxer group were significantly higher than those measured in the control group (BDav, P <.0001; , P <.01). In the boxer group, a robust correlation was found between increased BDav and frequency of hospitalization for boxing injuries (r 0.654, P <.05). The most common MR finding in the boxer group was volume loss inappropriate to age followed by cavum septum pellucidum, subcortical white matter disease