Hydrocephalus is a disorder occurring in the brain. It is characterized by an excessive accumulation of cerebrospinal fluid, the fluid in which the brain and spinal cord bathe. It is possible to distinguish several types, including normal pressure hydrocephalus, or chronic adult hydrocephalus. The management of hydrocephalus varies, from simple therapeutic observation to surgery.

Definition of hydrocephalus

Hydrocephalus refers to an increase in the volume of cerebrospinal fluid, or cerebrospinal fluid. This fluid circulates in the brain and plays a key role in the protection of the neurological sphere: it allows in particular to eliminate waste and absorb shocks that can damage brain structures. However, an excessive buildup of cerebrospinal fluid is a problem. It can cause the cerebral ventricles to dilate and increase intracranial pressure. The consequences of hydrocephalus are numerous and can affect the body at different levels.

Types d’hydrocéphalie

It is possible to distinguish several from hydrocephalus:

• obstructive hydrocephalus which is characterized by obstruction of the flow of cerebrospinal fluid;
• communicating hydrocephalus which corresponds to a problem of absorption of cerebrospinal fluid;
• normal pressure hydrocephalus, also called chronic hydrocephalus in adults, which constitutes a special case and which is still poorly understood to this day.

Causes of hydrocephalus

First of all, it should be noted that hydrocephalus can be congenital or acquired. This means that it can be present from birth or be the consequence of certain external parameters.

As the name suggests, obstructive hydrocephalus is caused by an obstruction in the brain. It can have several explanations:

• a brain tumor, especially in the event of a pineal tumor (in the pineal gland, or epiphysis);
• a malformation of the central nervous system such as the Dandy-Walker malformation;
• bleeding such as intraventricular bleeding (from the ventricles of the brain);
• meningitis.

Communicating hydrocephalus is usually caused by meningitis. This inflammation may in particular be due to:

• an infection ;
• blood loss.

Normal pressure hydrocephalus

Normal pressure hydrocephalus, also called chronic adult hydrocephalus, is a specific form of the disease whose origin is still poorly understood today. Appearing with age around sixty and seventy years, normal pressure hydrocephalus is characterized by the appearance of a triad of clinical signs:

• gait and balance disorders;
• urinary disorders marked by urinary incontinence;
• cognitive disturbances characterized by dementia.

Diagnosis of hydrocephalus

The diagnosis of hydrocephalus is generally based on a clinical examination followed by additional examinations. These differ according to the age of the patient:

• cranial ultrasound in newborns;
• cranial CT scan or magnetic resonance imaging (MRI) in older infants and children;
• adult diagnostic tests, including diagnostic lumbar puncture, diagnostic lumbar drainage, and lumbar perfusion test.

People affected by hydrocephalus

Hydrocephalus can appear at any age. In the case of normal pressure hydrocephalus, it seems to appear around the age of 60-70 years. 

Risk factors for hydrocephalus

The risk factors are still poorly understood to date. Family history has an influence. However, many other external parameters could have an impact. Premature infants have a higher risk of developing hydrocephalus. Nevertheless, the incidence of hydrocephalus has declined in recent years in developed countries thanks to advances in medicine.

Typical symptoms in infants

Hydrocephalus is the most common cause of increased head circumference in infants. It is due to the increase in intracranial pressure. Other consequences of hydrocephalus can be seen in infants: headache, irritability and screaming.

At any age, hydrocephalus can also have other consequences:

• lethargy;
• vomitings ;
• convulsions;
• strabismus;
• vision disturbances;
• learning disorders such as memory disorders, attention problems, or difficulties in processing information;
• deterioration of executive functions;
• motor disorders;
• urinary incontinence;
• dementia.

Typical symptoms of normal pressure hydrocephalus

Normal pressure hydrocephalus is characterized by a triad of clinical signs:

• gait and balance disorders;
• urinary disorders marked by urinary incontinence;
• cognitive disturbances characterized by dementia.

The treatment of hydrocephalus depends on many parameters including the cause, severity and course of the disorder. The age of the hydrocephalic patient is also taken into account.

Depending on the case, support may be based on:

• simple monitoring by imaging and measurement of the head circumference;
• lumbar punctures;
• a surgical procedure that consists of a ventricular bypass.

To date, there is no specific prevention for hydrocephalus. It is simply recommended that pregnant women strictly follow the recommendations of their doctor to prevent the occurrence of complications in children.