Hydrocephalus: What It Is, Causes, Symptoms, Diagnosis, and Treatment

Hydrocephalus is a condition that can occur at any age, including during fetal development.

Hydrocephalus, also known as water on the brain, is a condition that can occur at any age, including during fetal development. The term hydrocephalus is derived from the Greek words "hydro" meaning water and "cephalus" meaning head. It literally translates to "head filled with water."

What is Hydrocephalus?

Hydrocephalus occurs when cerebrospinal fluid (CSF) accumulates inside the skull, particularly in the brain ventricles and spaces, beyond normal levels. In childhood, this condition often results in an increase in head size.

Cerebrospinal fluid should not be thought of as normal water. It serves vital functions, such as protecting the brain from severe impacts, and it contains nutrients similar to those in our blood. About half a liter of CSF is produced daily in the brain, and this fluid is absorbed by the brain. In other words, CSF undergoes continuous production, circulation, and absorption processes in the body. It circulates through the brain’s spaces and the coverings that surround the brain and spinal cord. An excess production of CSF, absorption issues, or narrowing or blockage of the channels through which the fluid circulates can lead to fluid buildup. This accumulation of fluid creates pressure on the brain, which can cause significant damage. Various brain injuries and developmental, physical, and mental impairments can result from this pressure.

It is not a disease that can heal on its own or be treated with medication under a doctor's supervision; surgery is the only solution. The surgery must be performed as soon as possible after diagnosis. Delayed or no treatment can be fatal. Hydrocephalus can be diagnosed using various radiological techniques, even in the womb, making early diagnosis extremely important.

The disease can occur at any age, from fetal development to advanced age. However, the symptoms it causes vary depending on the age group.

What Are the Causes of Hydrocephalus?

Sometimes the cause of hydrocephalus is not clearly understood. The causes of hydrocephalus can be classified into two categories: congenital (present at birth) and acquired (developing later in life).

Congenital Hydrocephalus Causes:

• A condition affecting the flow of CSF that can be identified when a baby is born with hydrocephalus.
• Premature birth, which can lead to issues such as brain bleeding in some premature babies.
• Health issues such as spina bifida.
• Mutations associated with the X chromosome.
• Some rare genetic disorders (e.g., Dandy Walker malformation).
• Arachnoid cysts, which are fluid-filled sacs between the brain or spinal cord and the arachnoid membrane.

Causes of Hydrocephalus in Children and Adults:
Hydrocephalus in children or adults is usually caused by diseases, trauma, or injuries affecting the brain. This is known as acquired hydrocephalus.

• Infections in the membranes surrounding the brain and spinal cord (e.g., meningitis).
• Tumors in the brain.
• Stroke.
• Trauma or injuries to the head for various reasons.
• Blood clots in the brain, known as venous thrombosis.
• Bleeding in the brain.
• Narrowing in the channels through which CSF circulates, which may sometimes show symptoms later in life.

Causes of Hydrocephalus in the Elderly:
Hydrocephalus can develop in the elderly due to brain damage, brain hemorrhage, or certain infections. It may also be linked to chronic conditions that negatively affect blood flow, such as diabetes, heart disease, or high cholesterol. These conditions may contribute to the development of hydrocephalus, although the exact cause is not fully understood. In elderly patients, normal pressure hydrocephalus is commonly observed.

Hydrocephalus Symptoms

Hydrocephalus can manifest different symptoms depending on its type and the age of the patient.

Congenital Hydrocephalus Symptoms:

• Abnormally large head due to fluid accumulation.
• A scalp that is thin and shiny, with easily visible blood vessels.
• Swelling or tension at the soft spot on the top of the baby’s head (fontanel) due to fluid accumulation.
• Wide spaces in the skull.
• Nutritional problems and imbalances.
• Irritability.
• Vomiting.
• Seizures (epilepsy, convulsions).
• Constant drowsiness.
• Muscle stiffness and spasms in the legs and feet.
• Strabismus (eye misalignment) and vision problems.

Hydrocephalus Symptoms in Adults and Children:

• Headaches (Cerebrospinal fluid does not drain well in a lying position, so people may experience more severe headaches when waking up. Prolonged sitting can also increase headaches, and if untreated, these headaches may become constant as the disease progresses.)
• Neck pain.
• Feeling unwell, tired, and fatigued.
• Frequently falling asleep (in advanced stages, even coma can occur).
• Mental fog and frequent confusion.
• Vision problems, often blurred or double vision.
• Difficulty walking.
• Incontinence or difficulty controlling bowel movements.
• High-pitched crying in children, often short and sharp.
• Changes in facial appearance, along with changes in head size.
• Developmental delay in children.
• Slower and restricted movement.
• Increased irritability and uncontrollable mood swings.
• Seizures (epilepsy, convulsions).

Normal Pressure Hydrocephalus Symptoms:
This condition typically occurs in adults over 60 years of age. The main symptom is sudden falls without loss of consciousness.

• Difficulty walking, especially turning (they may walk as though there is a magnet on the ground).
• Memory problems and forgetfulness due to impaired mental function.
• Headaches.
• Incontinence or difficulty controlling bowel movements.

How is Hydrocephalus Diagnosed?

Thanks to advances in technology and medicine, neuro-radiological techniques are used for diagnosis. These techniques include MRI (CSF flow MRI) and CT scans. Through these methods, enlargement in the brain's spaces and changes in brain tissue due to the disease can be detected. When combined with a patient examination and observed symptoms, a definitive diagnosis of hydrocephalus can be made.

This disease can even be diagnosed before birth in the fetus. MRI and ultrasound are techniques used to determine the development of the brain and changes in the brain's spaces in the fetus, as well as to monitor these changes. After birth, an MRI procedure helps to identify the cause of the hydrocephalus seen in the baby.

How is Hydrocephalus Treated?

As with other diseases, early diagnosis is crucial in hydrocephalus. Treatment with medication is not possible for this condition. The only treatment option is surgical intervention, which can only be performed by neurosurgeons. There are various surgical methods, and the most appropriate method is chosen based on the factors causing hydrocephalus.

If the cause of hydrocephalus is the inability of cerebrospinal fluid (CSF) to circulate properly, and the blockage occurs in the circulation channels, a surgical method to remove the blockage must be selected. The cause of the blockage could be a tumor, cyst, or similar condition. If the blockage cannot be removed, the circulation channels within the brain may be altered through surgical intervention.

Shunt Surgery
In most cases, the fluid circulation cannot be restored to its original, healthy state, and the fluid is transferred to any empty space within the body. Generally, the fluid is transferred to a space in the abdomen or heart, where cerebrospinal fluid is easily absorbed. A long, flexible, silicone tube known as a "shunt" is used for this transfer. The system must function at a controlled, one-way speed, which requires a pump and fine tube under the scalp. This procedure prevents increased pressure inside the brain. Since CSF is produced daily in the brain, this system must work continuously. The system's parts are beneath the skin, but they can be felt during a physical examination. In babies, they may be visible externally. The shunt does not require a power source, such as a battery. After this procedure and with proper follow-up, patients can continue their lives without problems.

Endoscopic Ventriculostomy
Endoscopic systems (procedures performed with a camera) are the preferred treatment method for suitable patients today. This method, known as endoscopic third ventriculostomy (creating a new passage for fluid circulation) and aqueductoplasty (removing a blockage), does not require a shunt system. Endoscopic methods may also be preferred for patients who have issues with recurring shunt blockages, infection problems, or those whose shunt has been removed due to infections.

In this operation, a small skin incision (1-2 cm) is made, and through a small hole in the skull, an endoscope (camera) is used to reach the third ventricle. A passage is created in the lower part of the ventricle for cerebrospinal fluid to circulate. The accumulated fluid begins to drain through this passage. The surgery takes about an hour, and the patient is discharged the following day.

This method, which is much more advantageous than shunt surgery in suitable patients, does not involve any plastic tubes or systems placed in the body. The risk of infection is lower, and problems such as shunt blockage or malfunction do not occur. However, there are some surgical risks. On rare occasions, the opening created to allow fluid drainage may close spontaneously, and there may be effects on the optic nerves.

Generally, this method is not preferred in infants under one year old.

If the diagnosis is made during pregnancy, the baby should be delivered as soon as possible, and the necessary surgical intervention for the disease should be performed promptly.

Hydrocephalus is a potentially fatal disease if diagnosed late. Therefore, if symptoms are observed, it is important not to neglect follow-up and checkups at the nearest healthcare facility.