Acute white matter changes following sport-related concussion: A serial diffusion tensor and diffusion kurtosis...

Area of Science:

• Neuroimaging
• Sports Medicine
• Neurology

Background:

• Sport-related concussion (SRC) may lead to persistent physiological brain changes post-symptom resolution.
• Limited serial follow-up studies using comprehensive diffusion metrics in the acute SRC stages exist.
• Diffusion MRI offers a valuable method for assessing white matter integrity after SRC.

Purpose of the Study:

• To characterize acute white matter alterations in athletes within 24 hours of SRC using Diffusion Tensor and Diffusion Kurtosis Tensor metrics.
• To track changes in white matter metrics and clinical symptoms over an 8-day follow-up period.
• To investigate the relationship between subjective symptom recovery and objective physiological brain changes after SRC.

Main Methods:

• Utilized Diffusion Tensor Imaging (DTI) and Diffusion Kurtosis Imaging (DKI) to assess white matter integrity.
• Recruited high school and collegiate athletes diagnosed with SRC.
• Conducted serial MRI scans and cognitive assessments at 24 hours and 8 days post-injury, comparing with a control group.

Main Results:

• At 24 hours post-SRC, concussed athletes showed more symptoms and poorer cognitive performance than controls.
• Diffusion MRI revealed widespread decreases in mean diffusivity and increased axial kurtosis in concussed athletes within 24 hours.
• At 8 days, diffusion metric differences became more widespread, despite symptom and cognitive improvements, indicating ongoing physiological changes.

Conclusions:

• White matter alterations persist for at least 8 days post-SRC, even with symptom resolution.
• Current clinical recovery markers may not fully capture the extent of physiological brain recovery after SRC.
• Findings underscore the need for caution in return-to-play decisions to prevent potential long-term consequences of incomplete brain healing.