EsthersDoll,

It appears that your IICP was due to an increase in cerebrospinal fluid (CSF) since a spinal tap drain relieved the pressure. The more common issue is a brain bleed. Minor traumatic brain bleeds show up best at the third day. Later, and the brain usually has absorbed the blood. Earlier, and the blood has not pooled to an observable level. This would be similar to a ruptured aneurism but instead caused by the focused impact.

The axiom of not going to sleep for 12 to 18 hours or longer after a head trauma is to be able to maintain an observation of consciousness in case of a brain bleed. After 18 hours post trauma or longer depending on the source of information, the statistical likelihood of a brain bleed drops.

ICP can increase due to injuries that cause an increase in blood pressure due to a failure of the blood pressure regulating system in the brain, a brain bleed or a failure of the absorption mechanism that handles the overflow of CSF. The critical issue with ICCP is due to Second Impact Syndrome where the brain is impacted before the brain has had time to restore proper blood flow regulation. This can result in a catastrophic rise in intracranial blood pressure that ends up herniating the brain into the brain stem canal with fatal results.

Such increases in ICP especially those associated with high risk of further damage are associated with a severe increase in symptoms. The generic head ache or nausea is not usually associated with high risk.

An ambulatory person without disabling head aches or severe (over the toilet) nausea is rarely at risk.

The MRI may have noted an increase in ICP by noticing a decrease or increase in the fluid filled spaces in the brain. The sinus associated with drainage of CSF may have become engorged due to a failure to drain the CSF. A decrease in these spaces can be associated with abnormally high blood pressure in the brain as brain tissues swell.