Battle's sign

In medical terminology, Battle's sign, also mastoid ecchymosis, is an indication of fracture of the base of the posterior portion of the skull, and may suggest underlying brain trauma. Battle's sign consists of bruising over the mastoid process, as a result of extravasation of blood along the path of the posterior auricular artery. . The sign is named after William Henry Battle.

Another common bruising sign of a skull injury is raccoon eyes, the purplish discoloration around the eyes following fracture of the frontal portion of the skull base.