Hydrocephalus comes from the accumulation of cerebrospinal fluid within the brain cavities (ventricles) when the absorption mechanism (the cerebrospinal fluid absorption rate is normally equal to the production rate) is no longer functional. This pathology is characterized by an intracranial hypertension related to cerebrospinal fluid regulation issue The pathology origin can be congenital (1 to 4 birth out of 1000) or induced by different pathologies (secondary effects) and thus can reach a wide range of people (young child up to older people). Hydrocephalus at normal pressure can also reach people over 65 years old (1 to 5%).

Brain tumors

Brain tumors, second most common type of tumor for children, whatever the level of disease progression, can induce hydrocephalus.


In case a ruptured cerebral aneurysm has occurred (up to 10% of strokes), a secondary effect hydrocephalus may occur. Modification of the cerebrospinal fluid viscosity would be the root cause and the blood presence close to the liquid resorption areas generate hydrocephalus.

Severe traumatic brain injury

About 1.5 million brain injuries happen every year. 9% are considered as severe where a post-traumatic hydrocephalus can happen several weeks and even several months after the traumatism itself.


Hydrocephalus can be induced by an infectious mechanism reaching the ventricles within the brain but also by an obstruction of the cerebrospinal fluid absorption system

Shunt and valves issues

Valve disorders on implanted patients are regularly observed. 40% of dysfunction happen within 2 years after the surgery and 98% after 10 years. The disorder can be due a dysadjustment of the valve (for models with adjustment possibility) or an obstruction of the catheter/valve set.

As soon as the cerebrospinal fluid can not be derived, the intracranial pressure is no more stabilized and hydrocephalus symptoms quickly return.