Three covers wrap the brain. They are called the meninges: dura, arachnoid, and pia. A head injury can bruise the brain itself. It can also bleed into one of these layers. Where the blood collects gives the bleed its name. Look at the bleeds first, then the injury types.
Layers of the head
Skull → dura → arachnoid → brain. Watch which space fills up with blood.
Pick a bleed or an injury.
Pick a findingbrain bleeds and brain injuries
Brain bleeds: the spot gives the name
Types of traumatic brain injury (TBI)
What it is
Quick way to keep the bleeds straight:Epidural means an artery above the dura, and it fills fast. Look for a "lucid interval," a clear spell, then a fast drop. Subdural means a vein below the dura, so it fills slower. Subarachnoid brings a thunderclap headache. Intracerebral is a hemorrhagic stroke right in the tissue.