you can have an internal hematoma, sub dural hematoma na, epidural hematoma bleeding on beneath the scalp that will resolve itself? >> an epidural or sub dural hematoma would be below the skull. >> right. >> that's the difference between a hematoma which is bob the skull between the skin. >> right. >> hematoma outside the skull. >> correct. >> resolves itself sort of between the skull and the skin. >> correct. >> and then sub dural epidural is you actually have gone below the skull and you just in that dura which is what cushions the brain? >> correct. >> and you can have injuries like this could can certainly cause an epidural or a sub dural hematoma, correct? >> not necessarily the lacerations themselves but if there was head trauma, completely. >> i'm sorry. so if i just went up to this head and cut it with a razor blade or a scalpel, that would not you would imagine cause a sub dural or epidural hematoma? >> no. >> but if i took that same skull and let's say smashed on concrete, sufficient enough to cause that interior. >> uh-huh. >> so smash might be a term of art, but getting that i