Head impacts, changes in eye function in high school football players

Head impacts in youth sports, even when they don't cause symptoms of concussion, are a public health concern because these so-called subconcussive head impacts may result in long-term neurological issues if they are sustained repeatedly. This study looked at changes in measurements of near point of convergence (NPC), which is the distance from your eyes to where both eyes can focus without double vision, in 12 high school football players at 14 different times during a season. The NPC measurement matters because it has been shown to detect damage to neurons before symptoms appear. The frequency and magnitude of head impacts from all practices and games also were measured. Study findings suggest NPC values worsened with subconcussive head impacts, and that impaired NPC didn't rapidly recover. However, NPC values began to return to normal in midseason while players continued to incur head impacts, suggesting the system controlling eye movements may develop tolerance to recurrent subconcussive head impacts. The findings of this study may not be generalized because of its small size.