Acute IH vs. Chronic IH

Intracranial hypertension can be divided into two categories: acute IH and chronic IH.

Acute IH often occurs as the result of severe head injury or intracranial bleeding from an aneurysm or a stroke. It is characterized by a very rapid onset after the initial injury and extremely high intracranial pressure that can be fatal. The underlying cause of acute IH is brain-swelling or intracranial bleeding into the sub-arachnoid space that surrounds the brain. In many cases, a piece of skull is surgically removed to accommodate brain swelling and lower intracranial pressure. This can be life-saving.

In contrast, chronic intracranial hypertension is a neurological disorder in which the increased cerebrospinal fluid (CSF) pressure has generally arisen and remains elevated over a sustained period of time. It can either occur without a detectable cause (idiopathic intracranial hypertension) or be triggered by an identifiable cause such as an underlying disease or disorder, injury, drug or cerebral blood clot (secondary intracranial hypertension). It is frequently a life-long illness with significant physical, financial and emotional impact.

Chronic IH can cause both rapid and progressive changes in vision. Vision loss and blindness due to chronic IH are usually related to optic nerve swelling (papilledema), which is caused by high CSF pressure on the nerve and its blood supply.

In addition, individuals with this disorder often suffer severe pain. The most common form is a chronic headache, which is generally unresponsive to the most potent pain medication. 

Anyone can develop chronic IH, regardless of age, gender, ethnicity, race or body type. While the chronic form of intracranial hypertension is not usually fatal, current treatments for the disorder can result in serious, sometimes life-threatening complications.

Researchers are eager to identify the mechanism that underlies chronic intracranial hypertension. While no one is sure why IH happens, some researchers believe that the answer may involve resistance or obstruction of CSF outflow through the exiting pathways from the brain. Our mission at IHRF is to discover exactly why chronic IH occurs and to foster medical research to find better ways to treat, prevent and ultimately cure this disorder. While our primary focus is on chronic IH, such research may also lead to improved understanding and treatment of acute IH.