Bilateral epidural hematomas.

Sixty-four cases of bilateral epidural hematomas were reviewed. The factors of patient age, direction of injuring forces, location of hematomas, presence of associated skull fracture, and time interval between injury and onset of signs and symptoms were analyzed. The results of this analysis show that bilateral epidural hematomas may develop slowly indicate that they occur with traumatic forces predominantly oriented in the anteroposterior direction, have fewer overlying fractures associated with them than unilateral epidural hematomas, and commonly contain venous blood. the differences between unilateral and bilateral epidural hematomas in direction of injuring forces, frequency of overlying skull fracture, and type of hemorrhage suggests that varying mechanisms may be responsible for production of these hematomas. Serial angiograms and CT scans have shown delayed accumulation of blood in bilateral epidural hematomas. This finding challenges the theory that epidural hematomas develop within minutes following injury.