Fractures of the middle cranial fossa can involve the pterygoid and temporal bones. Normally, after an injury, blood and cerebrospinal fluid will flow through the pterygoid sinus and into the upper nasal canal and then out through the nostrils, forming a nasal leak. If the fracture line involves the rock of the temporal bone, blood and cerebrospinal fluid can flow through the middle ear and the ruptured tympanic membrane and out of the external ear canal, forming an aural leak. If the tympanic membrane is not ruptured, a nasal leak can form along the posterior nasal cavity of the Eustachian tube. Fractures of the temporalis often result in damage to the facial and auditory nerves, resulting in sensory or motor impairment of the face or hearing loss. If the fracture line is more medial, it can involve the optic nerve, the ophthalmic nerve, and the trigeminal nerve. A fracture of the external middle cranial fossa can cause temporal swelling. These are the typical clinical manifestations of cranial middle fossa fracture.