Hydrocephalus is a condition characterized by the excessive accumulation of cerebrospinal fluid (CSF) in the enlarged cerebral ventricles and subarachnoid space.

CSF is a fluid mainly produced in a structure in the brain called the choroid plexus. The remaining portion of CSF is produced by the cerebral tissue itself.

CSF first flows into the ventricular system of the brain, then moves into the subarachnoid space beneath the meninges, where it nourishes and meets the fluid needs of nerve cells in these areas.

What is Hydrocephalus in Children?
Hydrocephalus literally means “water on the brain.” In children, it is noticed due to an abnormal enlargement of the head. Cerebrospinal fluid (CSF) protects the brain and spinal cord from shocks. Additionally, CSF acts as a protective barrier against harmful substances in the blood through a mechanism called the blood-brain barrier.

CSF is continuously produced and absorbed, removing fluid from the brain and spinal cord. After circulating, it is absorbed into the bloodstream through the veins. Any obstruction or abnormality during the production or absorption phases can cause hydrocephalus. Hydrocephalus occurs due to an imbalance between CSF production and absorption inside the skull.

What Causes Hydrocephalus in Children?
Hydrocephalus in children is always related to increased intracranial pressure syndrome (ICP).

• Increased CSF production in the choroid plexus,
• Insufficient CSF absorption,
• Obstruction or narrowing along the CSF pathways can increase CSF volume, causing increased intracranial pressure.

The most common cause of hydrocephalus in children is a problem in CSF circulation, leading to excessive accumulation in the cerebral ventricles. Less commonly, it results from inadequate absorption. Unless ICP rises significantly, CSF production generally remains within physiological limits.

Enlargement occurs in the brain ventricles above the obstruction, causing brain tissue damage. If hydrocephalus develops before the cranial sutures close during infancy, the head circumference increases markedly. This prevents a major rise in intracranial pressure and brain tissue damage is relatively less.

If hydrocephalus occurs after the sutures close or suddenly, severe ICP develops and brain tissue damage increases.

Hydrocephalus is most often congenital between ages 0-2 (and may accompany other syndromes) or caused by intracranial hemorrhage. In older children and adults, it may occur due to brain infections, hemorrhage, head trauma, or brain tumors.

What are the Symptoms of Hydrocephalus in Children?
Symptoms vary by age but in the first two months may include:

• Abnormal enlargement of the head,
• Thinning of the scalp,
• Prominent veins on the scalp,
• Vomiting,
• Downward deviation of the eyes,
• Seizures.

In older children, symptoms such as nausea, vomiting, visual disturbances, and sensory or motor deficits may appear.

Brainstem involvement can affect vital functions (breathing, swallowing, etc.) causing slow heartbeat, systemic hypertension, and respiratory problems.

How is Hydrocephalus Diagnosed in Children?
Prenatal ultrasound can detect hydrocephalus during pregnancy. After birth, serial head circumference measurements should be taken and ultrasound prioritized before the anterior fontanel closes. While ultrasound can visualize the lateral ventricles well, the posterior fossa cannot be seen. After fontanel closure, CT or MRI imaging replaces ultrasound for diagnosis.

How is Hydrocephalus Treated in Children?
Hydrocephalus cannot be treated with medication. Surgical treatment aimed at the underlying cause is preferred. Therefore, a shunt (a drainage tube) is placed to divert CSF from the brain to another area of the body. This surgery is done with a thin catheter. Because CSF is continuously produced, the shunt must remain functional and open at all times. Shunts may become blocked or infected by microbes.

How Should Rehabilitation be Conducted in Children with Hydrocephalus?
Therapies should focus on strengthening the muscles in the affected areas and must be personalized. Balance and coordination improvement exercises should be implemented. Modern robotic rehabilitation can be used to enhance balance and facilitate gait training.

Occupational therapy helps the individual adapt to daily life. Sensory integration training is also provided to support regaining functional abilities.