Clinical features

Effects develop rapidly as the bleeding is arterial in origin and at high pressure.

Clinical features may include:

• patient is often a young adult
• commonly follows trauma to the temporal or temporo-parietal region
• scalp oedema above the ear may be present
• concussion may be followed by temporary recovery of consciousness for minutes or hours before the onset of drowsiness and possibly coma - a characteristic phenomenon referred to as the "lucid interval"
• there may be an ipsilateral, dilated pupil on the side of the expanding lesion; a bilateral III nerve palsy may follow as rising intracranial pressure produces tentorial herniation
• there may be signs of intracranial compression
• there may be progressive contralateral hemiplegia