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Hydrocephalus (also known as hydrocephalus) describes an excess of cerebrospinal fluid (CSF) in the skull and affects approximately one case per 1000 births. Cerebrospinal fluid is produced and reabsorbed in our brain every day. With a production volume of approx. 20 ml per hour, a total exchange of cerebrospinal fluid takes place four times a day. This cerebrospinal fluid serves as a buffer cushion to protect our brain. The cerebrospinal fluid is produced in the ventricles. These are four cavities in our brain. It flows through these four ventricles and then around the brain until it is reabsorbed in the meninges. If there is a blockage of the ventricles or their outlets, increased production of cerebrospinal fluid (rare) or reduced reabsorption of cerebrospinal fluid, hydrocephalus occurs.
In paediatric neurosurgery, we differentiate between
All these forms can occur individually or in combination.
There can be many reasons for hydrocephalus. A distinction is made between congenital and acquired forms. Hydrocephalus can therefore occur at any age. There are certain risk factors that may or may not be associated with the occurrence of hydrocephalus, including low birth weight, prematurity, male gender and maternal diabetes mellitus.
In foetuses and infants, the bone connections of the skull (so-called sutures) are still soft and deformable. If a lot of cerebrospinal fluid accumulates, the head can deform under the pressure. This usually results in a rapid increase in the size of the head (measurable with the head circumference) and a full and bulging fontanel.
If the skull bones are already closed, there is an increase in intracranial pressure, as the brain and ventricles cannot expand any further. The period of time during which hydrocephalus develops is also important.
If hydrocephalus develops within a short period of time, the brain cannot adapt quickly enough to the increasing pressure. Symptoms then tend to occur early and be severe. However, hydrocephalus can also develop slowly, in which case symptoms only appear later.
Increasing pressure in the head typically leads to mild irritability, headaches, nausea, vomiting, gait disorders or neurological deficits. Children also often show developmental delay and developmental milestones are not reached.
Clinically suspected cases are usually examined by paediatric neurologists or developmental paediatricians. In addition, a swelling of the eye nerve, so-called papilloedema, can be detected by means of an eye examination, which would indicate increased pressure in the head.
If the suspicion remains after the examinations, the next step is imaging of the skull. In infants (as long as the fontanel is open), this is an ultrasound. If the suspected diagnosis is then confirmed by ultrasound, a magnetic resonance imaging (MRI) scan is performed to evaluate the cause. In children with a closed fontanel, an MRI is performed directly.
The advantage of ultrasound diagnostics is that it can be carried out while the patient is awake, but with poorer image quality than an MRI. For an MRI, on the other hand, infants and children up to the age of around seven to nine years must be anaesthetised. With its better image quality, MRI usually also confirms the cause of the hydrocephalus.
In the vast majority of cases, surgery is unavoidable. Hydrocephalus does not usually improve spontaneously. The current treatment options for hydrocephalus include two paediatric neurosurgical techniques in particular: a so-called ventriculoperitoneal shunt or a so-called endoscopic third ventriculostomy.
If another disease leads to hydrocephalus (such as a tumour), this must also be treated. As a result, the hydrocephalus usually regresses.
With the deposit of a ventriculoperitoneal shunts (VPS) a small "drainage tube" (shunt) is created between the head and the abdominal cavity. This restores the outflow of cerebrospinal fluid.
The VPS is inserted as follows: The child is placed in a supine position under anaesthetic. After minimally shaving the hair, an approx. 2 cm incision is made on the front right side of the head. A small hole is then drilled into the skull bone. With the help of intraoperative imaging, the shunt tip is inserted into the ventricle. The shunt tip is then connected to the rest of the shunt. This "drainage tube" runs under the skin and is connected to a valve. The valve is located approximately behind the ear and can be felt through the skin. A pressure level can be set on the valve, at which point the valve opens, allowing cerebrospinal fluid to drain into the abdominal cavity. This process can be regulated magnetically and can be changed from the outside with a template if necessary.
The valve behind the ear is connected to an additional tube that runs under the skin towards the abdomen. At the UKBB, the insertion of the "drainage tube" is carried out together with paediatric abdominal surgeons. They receive the tube at the level of the abdomen and insert it into the abdominal cavity using a minimally invasive (laparoscopic) method under visual control. This requires two small incisions on the abdominal wall and the navel, which are then sutured and covered with a sterile dressing. Finally, the incisions on the abdomen and head are sutured closed again and sterilely covered. The operation takes between 30 and 60 minutes.
Alternatively, in selected cases (especially obstructive hydrocephalus), the Endoscopic third ventriculostomy (ETV) is performed. Also in the supine position and under anaesthetic, an approx. 2 cm incision is made on the front right side of the head and a small hole is then drilled into the skull bone. A camera-controlled endoscope (a metal rod with a camera and light source at the front end) is inserted into the ventricles through this hole. A small hole is then made in the floor of the third ventricle to restore the outflow of cerebrospinal fluid. This hole is made using a small balloon, which creates a new outflow (known as a stoma) between the ventricles. The ventricle is then left again and the access incision is closed. The operation takes between 20 and 30 minutes.
The two surgical techniques are on a par with each other. ETV shows a lower risk of infection compared to VPS. However, the success rate of ETV in children under six months of age is lower compared to VPS. In addition, ETV is not suitable for every form of hydrocephalus. Our experienced paediatric neurosurgeons will therefore discuss with you which method has the highest success rate in each case and is therefore the most suitable for your child.
After the operation, the success of the shunt or ETV is checked using imaging in the follow-up visits and the valve is fine-tuned at the VPS if necessary.
Your child will be cared for by our paediatric neurosurgery team at UKBB throughout the entire hospital stay. Your child will come in the day before the operation, will be examined again by our team and the anaesthetists and can then sleep at home if you wish. Your child will be operated on the next day. He or she will then be monitored in the recovery room and after a few hours will be transferred to the paediatric surgery ward (ward B, 3rd floor). Babies younger than six months are monitored in the intensive care unit (1st floor) after the operation until the following day.
On the day of the operation, a companion from the Pro UKBB Foundation's parent support service (BELOP) will be at your disposal. She will accompany you until your child has fallen asleep and show you where he or she will wake up. In between, she will help you to find your way around the hospital. During the entire time, your child will be looked after by our paediatric neurosurgery team.
As soon as your child has recovered from the operation, they will be allowed to go home again. You can be with your child during the entire time and contact the paediatric neurosurgery team, who will visit you and your child every day for a ward round.
The prognosis for treated hydrocephalus is generally very good. The children often develop well and have a good quality of life. In some cases, however, the prognosis depends on the underlying disease and its accompanying symptoms. Accordingly, the prognosis can also be less favourable. Complications following UTP are rare overall (approx. 5% in total). The most common complication is a re-occlusion of the stoma or permanent hydrocephalus despite the stoma. In these cases, the ETV must be repeated or a VPS inserted. Other rare risks are infections, haemorrhages, seizures or a stroke.
Acute (short-term) complications after VPS implantation occur in approx. 3-5% of cases. These are mainly infections (5-15%), haemorrhages and wound healing disorders. In rare cases, so-called overdrainage can occur. This means that the shunt drains too much cerebrospinal fluid and there is a pull on the remaining brain tissue. This can lead to haemorrhaging, which requires surgery. The long-term complication rate (over the entire lifetime) is significantly higher with VPS. In around 20-30% of cases, children with VPS must be expected to undergo a so-called shunt revision (new operation with replacement of the shunt or parts of it) in the course of their lives, as fractures, disconnections, blockages, displacement and infections in the shunt system can occur. As a rule, children need the VPS for the rest of their lives. A VPS can rarely be completely removed again in the course of a child's life.
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The Medgate Kids Line provides quick and uncomplicated medical advice if your child is unwell. The medical team of our partner Medgate is available to you by telephone around the clock.
For emergencies abroad: Call the emergency number of your health insurance company. You will find this number on your health insurance card.
More information: On the Page of the emergency ward you will find everything you need to know about behaviour in emergencies, typical childhood illnesses and waiting times.
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