硬脑膜外表面可见一血块，此为硬膜外血肿。此部位的出血几乎总是脑膜中动脉撕裂造成的。
A blood clot is seen over the external surface of the dura. Thus, this is an epidural hematoma. Such a location for hemorrhage is virtually always the result of trauma that causes a tear in the middle meningeal artery.