The sequelae of a head injury from a car accident are primarily related to the degree of trauma suffered to the head. If an injury to the head occurs as a result of a car accident and there are no abnormalities on imaging, symptoms such as dizziness, headache, nausea and vomiting, insomnia, and anxiety may persist after the injury. If the symptoms persist for more than three months after the injury there may be sequelae, which are called post-traumatic brain injury syndrome. There may also be intracranial hematoma from head injury caused by a car accident, and if the hematoma is large, the patient may have a combination of sequelae such as epilepsy, prolonged coma, and hydrocephalus.