Young athletes who have sustained one or more concussions without persistent cognitive complaints at least one year post-injury

Young athletes who have sustained one or more concussions with persistent cognitive complaints at least one year post-injury in spite of medical and cognitive treatment intervention.

Participants will receive an intravenous (IV) dose of 300 MBq of Neuraceq™ in a volume of 10 mL or less. A 30 minute duration PET image will be acquired starting immediately after Neuraceq™ injection. A second 20-minute duration PET image will be acquired starting 90 minutes after Neuraceq™ injection.

Participants will receive an intravenous (IV) dose of 300 MBq of Neuraceq™ ([F-18]Florbetaben) in a volume of 10 mL or less. A 30 minute duration PET image will be acquired starting immediately after Neuraceq™ injection. A second 20-minute duration PET image will be acquired starting 90 minutes after Neuraceq™ injection. Imaging data will be reconstructed using standard iterative reconstruction algorithm and with CT-based attenuation correction. Images will be interpreted both visually and semi-quantitatively (cortical-to-cerebellum standardized uptake value rations) for 6 target cortical regions of interest (frontal, temporal, parietal, anterior cingulate, posterior cingulate, and precuneus), using the whole cerebellum as the reference region.

Participants will complete a set of cognitive questionnaires to assess presence or absence of cognitive complaints. Altered cognitive performance will be defined as either one score of more than 2 standard deviations or two scores of 1 standard deviation below the age-adjusted norm or estimates of baseline premorbid function (using the Barona Index) on tests of attention and/or memory.

Participants will complete a set of cognitive questionnaires to assess presence or absence of cognitive complaints. Significant cognitive complaints will be defined as scores of 1 standard deviation below the mean on the Multiple Ability Self-Report Questionnaire (MASQ).