A 17-year-old female playing soccer goes for the ball and accidentally collides with a member of the opposing team. She does not lose consciousness but appears dazed. The coach calls her to the sideline. She becomes nauseated, then vomits. On questioning, she is answering questions appropriately but does not recall why she is on the field. She vomits a second time and is taken to the hospital where a computed tomography (CT) scan of the brain without contrast demonstrates a small area of traumatic hemorrhage in the left frontal lobe (Figure 30.1).