You can see this at play with the hot dog: the sandwich and sausage were both invented elsewhere, so to celebrate them separately as uniquely American on America's day of independence would present an empty gesture, immediately undermined by the tools used to make it.
An Ommaya reservoir is an intraventricular catheter system that can be used for the aspiration of cerebrospinal fluid or for the delivery of drugs (e.g. chemotherapy) into the cerebrospinal fluid.n Ommaya reservoir is an intraventricular catheter system that can be used for the aspiration of cerebrospinal fluid or for the delivery of drugs (e.g. chemotherapy) into the cerebrospinal fluid.
Basically a subdural haematoma is bleeding between the brain cover and the brain itself, whilst an epidural haematoma is a bleed between the brain cover and the skull. The blood vessels running in the space between the brain and the skull can rupture and bleed during a traumatic brain injury, also known as tbi, when there is a blow to the head.