Snapshot A 45-year-old man is brought to the emergency department after being found down in the park. The patient reports that he was physically assaulted by a group of men. Since then he reports episodes of rhinorrhea and occasional leakage from the ear. Physical examination is notable for periorbital and retroaurticular ecchymosis without evidence of a CSF leak. Non-contrast head CT demonstrates a basilar skull fracture but with no evidence of an intracranial hemorrhage. Neurosurgery was consulted, who recommended no surgical intervention but to be admitted for frequent neurological assessments. Introduction Definition breaking of bone at the base of the skull Associated conditions cervical spine injury retrobulbar hematoma distinguishing features proptosis blurry vision pain with extraocular movements elevated intraocular pressure Etiology high-velocity blunt trauma (e.g., motor vehicle collisions and pedestrian injuries) penetrating injuries (e.g., gunshot) Pathogenesis the location of the fracture predicts injury temporal fractures (most common) carotid injury CN VII and/or CN VIII injury mastoid cerebrospinal fluid (CSF) leak anterior skull base fractures orbital injury nasal CSF leak CN I injury central skull base fractures carotid injury CN III, IV, V, and/or VI injury posterior skull fractures cervical spina injury vertebral artery injury CN IX, X, and XII injury Presentation Symptoms altered mental status nausea vomiting Physical exam cranial nerve deficits (depending where the fracture occured) hemotympanum blood pooling behind the tympanic membrane CSF rhinorrhea or otorrhea periorbital ecchymosis (raccoon eyes) associated with anterior skull base fractures retroaurticular or mastoid ecchymosis (Battle sign) Imaging Noncontrast head CT indication initial imaging study for patients with head trauma findings skull fractures difficult to assess if the fracture is linear or non-displaced Studies Making the diagnosis this is a clinical diagnosis supported by head imaging Treatment Managed expectantly required urgent neurosurgical evaluation and frequent neurology checks Complications Meningitis CSF leak Cranial nerve palsies Cavernous sinus thrombosis