Hydrocephalus is an abnormal enlargement of the ventricles of your brain. Cerebrospinal fluid (or CSF) in the ventricles protects the brain and spinal cord. It also contains nutrients necessary for your brain tissues to function.
Removal of waste products is another duty of the CSF. The amount of CSF in the ventricles is approximately 150 ml at any given time. The total production of CSF in 24 hrs is approximately 500 ml. Blood absorbs CSF to keep its volume within limits.
Any imbalance between the production of CSF by the ventricle and its absorption by the blood causes hydrocephalus. In children, the ventricles start bulging and increase the size of the head. In adults, it puts a lot of pressure on the brain to cause various symptoms.
The most common treatment for hydrocephalus is shunt surgery. A shunt is an alternative pathway for the CSF to flow out of the ventricles. In this surgery, the surgeon diverts the excess CSF into another part of the body, usually the abdomen. From there, it gets absorbed by the blood to keep its volume within limits.
Causes
Hydrocephalus is a condition and not a disease by itself. It usually occurs when there are blocks in the flow of CSF through the ventricles. Whenever there are blocks, the CSF accumulates in the ventricles and fails to get back into the bloodstream.
Your hydrocephalus may also be congenital or present at birth. The leading causes of congenital hydrocephalus are:
- Aqueductal stenosis – The CSF on its way for reabsorption to the bloodstream passes through a duct, by the name Aqueduct of Sylvius. Blocks in this passage may be present at birth.
- Type 2 Chiari malformations – In this condition, the cerebellum and brain stem descend into the spinal canal. It obstructs the flow of CSF through the ventricles.
- Arachnoid cysts – These are bulges in the lining of meninges filled with CSF.
- Dandy-Walker syndrome – There is an abnormal enlargement in the size of the fourth ventricle due to obstruction in its outlets.
You have acquired hydrocephalus if it develops later in life. The main causes are
- Intraventricular hemorrhage – It occurs mostly in newborns. Haemorrhage or bleeding in the ventricles leads to the formation of scar tissue that restricts the reabsorption of CSF.
- Meningitis – In this condition, there is an inflammation of the meninges, the protective membrane around the brain and spinal cord. The injury to the meninges causes problems with the flow and absorption of CSF. In India, one of the main causes of meningitis causing hydrocephalus is Tuberculosis.
- Head injuries – Damage or bleeding into the ventricles due to head injuries leads to the formation of scars. These obstruct the flow and absorption of CSF.
- Brain tumours – Tumours may grow into the ventricles to obstruct the flow of CSF.
Symptoms
The symptoms of hydrocephalus vary from person to person. It varies with the age of occurrence as well. Most of the symptoms are due to the pressure on the brain by the CSF. Some of the common symptoms of hydrocephalus are as below.
1 . Congenital hydrocephalus:
If your newborn has congenital hydrocephalus, some of the common symptoms are:
- An abnormally large head at birth, which increases rapidly in size with time
- A large and tender soft spot in the middle of the head
- Very prominent scalp veins
- Downward deviation of the pupils of the eye or ‘sunset sign.’
- Bouts of vomiting
- Being irritable or very sleepy most of the time
- Sudden seizures
2. Acquired hydrocephalus:
In children and adults with acquired hydrocephalus, some of the common symptoms are
- Headaches- It is usually worse in the mornings and gets better through the day
- Neck pain
- Nausea and vomiting that is worse in the mornings
- Blurring and double vision
- Difficulty in balancing as well as walking
- Irritability, lack of concentration, confusion
- Bladder problems
3. Normal-pressure hydrocephalus:
If you are an adult with normal pressure hydrocephalus, you will have any of these symptoms, as well as some others.
- Problems with walking – You will find it difficult to walk. The biggest challenge will be to take the first step. You may feel as if you are rooted to the spot. Once you start walking, you tend to shuffle your feet than to take proper steps.
- Urinary problems – You will need to pass urine very frequently. Most often, the need will be very urgent as well. As it gets worse, you may have a total lack of bladder control.
- Problems with thinking or Dementia – As the situation worsens, it affects your thought process as well. You will become slow in responding to questions as well as situations.