The middle meningeal artery was part of the Human circulatory system and provided blood to the brain. It was any one of three arteries which supplied blood to the brain and neighboring areas. Damage to such an artery, if untreated, could result in the death of the affected patient. A fundoscopic examination would be unrevealing of any brain damage resulting from the artery's injury.
Pavel Chekov, who had traveled back in time to the 20th century, tore his meningeal artery in a fall while attempting to flee United States Navy personnel on the aircraft carrier USS Enterprise. He was diagnosed by doctors of the period as suffering from an expanding epidural hematoma. Doctor McCoy was able to save him "from the hands of 20th century medicine" by correctly diagnosing Chekov's condition as a tearing of the middle meningeal artery, to which McCoy's 20th century counterpart snickered and asked if McCoy's degree was in dentistry. (Star Trek IV: The Voyage Home)