Well, yes, it is possible to have dilated pupils when you get a concussion. As we know that it you have a concussion, your brain function is temporarily affected, at times causing pupil dilation even in light. So in other words, we can say that a concussion can cause dilated pupils, because the condition interferes with the message delivery system in the brain. And if you get dilated pupils, it will make you more sensitive to light and may cause additional vision problems. Also, high blood pressure, hyperventilation, muscle tensions are the most common ones which can be related to dilated pupils. So just be careful to avoid having them.