Hydrocephaly is caused by an excessive amount of cerebrospinal fluid (cerebrospinal fluid) in the brain cavities. The problem is that this cerebrospinal fluid is not absorbed, or that the absorption is slower than usual. The fluid surrounds the brain and passes through the ventricle system and other brain cavities in the brain.
The cerebrospinal fluid is normally produced at a constant rate. Because it is absorbed into the bloodstream, the total amount of fluid remains about 150 ml. With hydrocephaly, however, this amount is much larger.
One of the causes is a blockage. This blockage runs somewhere along the route where cerebrospinal fluid flows. A cause for the occurrence of such blockages is a disorder in the development of the brain in the unborn baby. Hydrocephaly is named depending on where the block is located.
There may be other causes of hydrocephaly:
The bones that enclose the brain and spinal cord form a closed cavity with a limited volume. Any increase in the amount of tissue or liquid in this closed space leads to an increase in pressure. As the volume of cerebrospinal fluid increases, the intracranial pressure increases. This increases the ventricles and compresses the brain tissue. It is these changes that cause the symptoms of hydrocephaly.
The skull in babies and small children is soft and can still expand. Sometimes it is noted that the head of the baby is larger than normal. Sometimes there are signs of, among other things, lethargy and irritability.
Sometimes the disorder can be seen when an ultrasound is taken during pregnancy. Often you will be referred to a doctor in a specialized hospital where specialized ultrasound equipment is also available. Usually radiographs are made of the skull. Sometimes scans (CT and MRI scan) are also made of the brain. Sound waves are used to visualize the ventricles.
An operation is the most suitable form of treatment. The aim of the treatment is to reduce or eliminate the blockage that prevents the absorption of cerebrospinal fluid into the bloodstream. Usually a tube (drain or stent) is inserted, which diverts the cerebrospinal fluid (beyond the blockage). Sometimes the cerebrospinal fluid is led to the abdominal cavity or directly to the bloodstream. In children, the drain often has to be replaced over time by a larger one.
The long-term effects depend on the severity of the hydrocephaly. In adults, the sooner treatment is started, the less likely it is that brain disorders will develop in the long term. Long-term effects do occur in some babies, such as a delay in intellectual development and / or a generally delayed development.