Hydrocephalus is the accumulation of cerebrospinal fluid in brain cavities (ventricles) for different reasons. Excessive accumulation of fluid in the fluid-filled cavities in the brain can lead to various findings by applying compression to the brain, in different disease scenarios. Hydrocephalus may be congenital (primary hydrocephalus) and also may develop as a result of different brain diseases (secondary hydrocephalus). Examples of these diseases include meningocele, meningomyelocele, encephalocele, Dandy-Walker malformation and other rare congenital defects.

Hydrocephalus is the growth and expansion of ventricles that are filled with cerebrospinal fluid in the brain tissue as a result of the increasing amount of this fluid. In normal healthy individuals, the cerebrospinal fluid is produced by specialized cells in these chambers and is reabsorbed after flowing through and around the chambers and the cortex of the brain and the spinal cord. The reason for this fluid increase in hydrocephalus cases is either an increase in the production rate of this fluid or a reduction in its absorption rate. Sometimes the fluid can accumulate in the ventricles and hydrocephalus may develop as a result of congestion due to congenital adhesion or tumors on the way to the area where it is absorbed.

Symptoms

Symptoms of hydrocephalus may vary by age.

In newborns (0 to 2 months): Abnormal growth of the head, thinning of the scalp, veins in the head becoming more prominent, vomiting, restlessness, eyes that slide down, seizures or being unable to communicate.

In children (2 months and older): Abnormal growth of the head, headache, nausea, vomiting, fever, double vision, restlessness, regression in speaking and/or walking ability, communication disorder, loss of sense and motor functions, seizures, vision disorders may be encountered. Older children may have difficulty staying awake or waking up.

Diagnosis

1. Magnetic Resonance Imaging (MRI) is the gold standard. With these examinations, the brain’s own tissue can be evaluated in detail. In addition, the movement of cerebrospinal fluid in the brain tissue between cells and the flow of this fluid within and around the brain and the ventricle and channels can also be evaluated. In addition, pathologies such as tumors causing hydrocephalus can also be detected.
2. Magnetic resonance imaging (MRI) methods that show the flow of cerebrospinal fluid: These examinations are especially used in situations that prevent the flow of cerebrospinal fluid. Although large tumors and other large-scale pathologies that obstruct fluid flow can be diagnosed by regular MRI, small sized tumors and in some cases narrownesses and obstructions in the way of fluid flow, that are congenital or acquired later, may not be seen in regular MRI. In such cases, MRI examinations that show cerebrospinal fluid flow may also be used.
3. Diagnosis can be made by ultrasonography in newborns.
4. Computed Tomography (CT) is also frequently used in hydrocephalus, although it is better in showing the bone tissue. It also shows the hemorrhaging in patients who recently experienced hemorrhaging.

Treatment

1. Inserting a shunt: The purpose of shunt insertion is to transfer the accumulated excess fluid in the brain cavities to different spaces of the body. In this process, a catheter is inserted into the ventricles in the head, this catheter is connected with a pump, a second and longer catheter is connected to the other end of the pump, then this catheter is guided to the abdominal cavity under the skin and its tip is placed inside the abdomen. In this way, the excess fluid in the brain is transferred into the abdomen. The excess fluid is absorbed from the abdomen. Combining the catheters that lead to the brain and to the abdomen just above the skull, the pump allows the cerebrospinal fluid to flow in a controlled manner above a certain pressure value. Thus, the fluid accumulated in the brain is discharged to another part of the body. The abdominal cavity is often used to drain this fluid. The other end of the catheter that goes to the abdomen may also be connected to different parts of the body. In some cases, this fluid may be discharged into the chest cavity or into the heart with the help of a vein in the neck that leads to the heart. The shunt pumps that are used can have a fixed pressure setting or this pressure can be adjusted from the outside after insertion. The choice is made according to the clinical status of the patients. Patients with a shunt are closely monitored. Failure in shunt operation or infection may be encountered. Infection usually occurs in the first 6 weeks after surgery, but also may be observed later. Shunts with antibiotics may be used in patients with a recurrent shunt infection.
2. Endoscopic third ventriculostomy: This treatment option may be used in case of the mechanical obstruction of the pathways that ensure fluid transfer. Not all patients with hydrocephalus may be suitable for this treatment. In this treatment option, to ensure fluid flow in the ventricles (fluid-filled spaces of the brain), a new hole is opened with an endoscope by accessing these spaces and the flow of accumulated fluid is ensured.