MRI Shows Whether Concussed Athletes Ready to Return to Sport

Athletes who sustained acute concussions may still have abnormal cerebral blood flow (CBF), even if they appear to be clinically ready to return to play, according to a study presented at the annual meeting of the Radiological Society of North America (RSNA).

Researchers from the Medical College of Wisconsin in Milwaukee sought to evaluate changes in CBF after sports-related acute concussion by using advanced arterial spin labeling MRI.

The study group comprised 18 football players, median age 17, who had sustained an acute concussion, and 19 matched non-concussed controls. The participants were scanned within 24 hours of injury and again eight days later. They completed the Sports Concussion Assessment Tool 3 (SCAT3) and Standardized Assessment of Concussion (SAC) during assessments visits as well. Clinical assessments had also been obtained for both groups before the football season.[[{"type":"media","view_mode":"media_crop","fid":"43711","attributes":{"alt":"Yang Wang, MD, PhD","class":"media-image media-image-right","id":"media_crop_1536690571222","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"4813","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"float: right; height: 213px; width: 160px; border-width: 0px; border-style: solid; margin: 1px;","title":"Yang Wang, MD, PhD. ©RSNA 2015.","typeof":"foaf:Image"}}]]

"This measurement of blood flow is fully noninvasive, without radiation exposure," coauthor Yang Wang, MD, PhD, said in a press release. "We use arterial blood water as a contrast tracer to measure blood flow change, which is highly associated with brain function."

The researchers found that that the players in the control group did not have any changes in CBF between the two scans. The concussed players showed no clinical impairment by day eight, despite significant impairment as per clinical assessment at 24 hours post-injury, but their scans showed a significant decrease in CBF.

"In eight days, the concussed athletes showed clinical recovery," Wang said in the release. "However, MRI showed that even those in clinical recovery still had neurophysiological abnormalities. Neurons under such a state of physiologic stress function abnormally and may become more susceptible to second injury."

The researchers concluded that these findings could have important implications for clinical decisions regarding when concussed athletes are allowed to resume their sport.