A study of former athletes demonstrated significant increase in uptake of the TSPO ligand [11C]DPA-713 within former National Football League (NFL) players as compared with healthy, age-matched controls.18 Similarly, the TSPO ligand [18F]DPA-714 was recently used to study microglial activation in collegiate athletes following a sports concussion, compared with healthy, age-matched controls.19 That study demonstrated persistent elevated neuroinflammation in collegiate athletes who were diagnosed with a sport concussion and cleared for unrestricted return to play based on a clinical recovery. Here, TSPO is linked to brain injury.