In terms of prevalence, hydrocephalus ranks second in pediatric neurosurgery, ahead only of trauma. That is why the treatment of hydrocephalus in children is such an urgent problem. Thanks to modern diagnostic methods, significant advances in treatment have been achieved. And if 25 years ago the majority of patients had practically no chance, today the methods of treatment are effective and save 95% of patients.
What is hydrocephalus?
Hydrocephalus is an excess accumulation of fluid in the head. More precisely, in the cavities of the brain containing cerebrospinal fluid. Another well-known name for the disease is dropsy of the brain, it is translated from Greek ("hydro" - water, "cephal" - head). That is literally “water in the head”. But it is worth noting that this name is not entirely accurate. In children with hydrocephalus, an excess amount of fluid accumulates in the head, but this is not water at all, but cerebrospinal fluid (cerebrospinal fluid), which protects and nourishes the nerve cells of the brain and spinal cord.
Normally, CSF is in the brain and spinal cord. In the head, the cerebrospinal fluid is located in the cavities of the brain: the four ventricles, between the meninges and in the cerebral cisterns. CSF constantly circulates between the cavities of the brain due to the presence of a system of holes. It is formed from blood, and about 0.5 liters of cerebrospinal fluid are formed per day. In a newborn, the total amount of cerebrospinal fluid is 5 - 20 ml, and in infants it is already 40 - 60 ml. Normally, the cerebrospinal fluid occupies about 10% of the volume of the cranial cavity. The composition of the cerebrospinal fluid regularly changes 3 to 4 times per day.
The amount of cerebrospinal fluid is regulated by two processes: formation and absorption.
The formation of cerebrospinal fluid occurs in the walls of the cerebral ventricles. Absorption takes place in the venous sinuses, which are located at the base of the brain. Both processes are equally important, a balance must be observed between the formation and release of cerebrospinal fluid. In case of imbalance in the cerebrospinal fluid system, an excess amount of cerebrospinal fluid may accumulate. This is how hydrocephalus develops.
What is cerebrospinal fluid for?
Surely everyone is wondering why we need liquor in our heads. Why is it so conceived? It turns out that mother - nature is very smart, because the liquor performs important functions.
Three functions of the cerebrospinal fluid, which are known to scientists:
- Protection of nerve cells from irritants and external mechanical influences.
- Removal of metabolic products and substances harmful to the brain, supplying it with nutrients.
- Stabilization and maintenance of normal intracranial pressure.
Types of hydrocephalus
Violation of patency of cerebrospinal fluid
There are the following types of hydrocephalus:
- Occlusal or closed.With this form of hydrocephalus, the opening through which the cerebrospinal fluid flows out is closed by some form of formation, for example, a tumor or cyst.
- Communicating or open.In this case, the cause of hydrocephalus is a failure in the cerebrospinal fluid absorption system, which can occur in a child who has had an infection (for example, meningitis).
- Hypersecretory.This form is quite rare. The reason is the increased production of cerebrospinal fluid, which can occur when there is a violation in the choroid plexuses of the ventricles of the brain.
Depending on the place of excess accumulation of cerebrospinal fluid
Hydrocephalus is divided into the following forms:
- Outdoor. In this case, there is an excessive accumulation of cerebrospinal fluid between the membranes of the brain.
- Internal.With it, an excess amount of cerebrospinal fluid accumulates in the ventricles of the brain. If the amount of CSF increases in two symmetrical ventricles at the same time, this is called internal symmetrical hydrocephalus. With unilateral hydrocephalus, the excess volume of cerebrospinal fluid accumulates mainly in one of the ventricles.
- Mixed.In this case, an excessive accumulation of cerebrospinal fluid is observed both in the ventricles and between the membranes of the brain.
By the level of cerebrospinal fluid pressure
Hydrocephalus is divided into the following forms:
- Normotensive.At the same time, the cerebrospinal fluid pressure is within the permissible norm and is less than 80 millimeters of water column in newborns, and less than 100 mm in older children. aq. Art.
- Hypertensive.The cerebrospinal fluid pressure is increased.
- Hypotensive. Low cerebrospinal fluid pressure is characteristic.
Due to development
There are two forms:
- Congenital hydrocephalus... The child is already born with an excess amount of cerebrospinal fluid in the head.
- Acquired, which is of several types:
- post-inflammatory, which develops after neuroinfections;
- tumor, in which the tumor blocks the outflow of cerebrospinal fluid or, conversely, stimulates its increased production;
- with vascular diseases of the brain;
- idiopathic, when the cause of hydrocephalus is not clear.
With the flow
Hydrocephalus is usually divided into several forms.
- Progressive... With her, the excess of cerebrospinal fluid rapidly increases.
- Stationary... With her, the amount of cerebrospinal fluid is consistently the same, does not increase or decrease.
- Regressive... With this form, the amount of cerebrospinal fluid gradually decreases.
By the degree of activity of the process
Allocate active and passive forms.
Also distinguish compensated and decompensated... In the stage of compensation, the tissues and structures of the brain are not compressed and there are no pathological symptoms (manifestations) from the nervous system.
Causes and mechanism of development of hydrocephalus in children
Most often, hydrocephalus is detected up to three months of age, in boys it develops more often.
In general, neurosurgeons have more than 180 causes that can cause the development of hydrocephalus.
1) In more than half of the cases, the increase in the ventricles of the brain in the fetus occurs due to an excess of cerebrospinal fluid. It occurs in conjunction with malformations of the central nervous system (CNS). For example, with the Dandy-Walker or Chiari anomaly.
- About 20% of babies are born with hydrocephalus due to intrauterine infection. The most common among them is cytomegalovirus, followed by herpes, toxoplasmosis, syphilis and other infections. Dangerous for pregnant women and childhood infection - rubella, which causes multiple defects in the development of the fetus. Also, the cause of the development of hydrocephalus can be an injury received during childbirth. About 2% of cases of congenital hydrocephalus are attributable to a genetic mutation in the 11th gene. This mutation is more common in boys.
- Hydrocephalus in children under two years of age in 80% of cases is a consequence of congenital malformations of the central nervous system. It is characterized by a progressive course.
- The remaining 20% of cases are perinatal injuries (received from the 28th week of pregnancy to 7 days after birth) and meningoencephalitis (inflammation of the brain and its membranes) suffered in the first 28 days of life.
- In children over two years of age, the main cause of development is tumors that impede the outflow of cerebrospinal fluid. Then, according to the frequency of occurrence, there are the same reasons as in newborns.
- Hydrocephalus can develop as a result of a pronounced displacement of cerebral structures by volumetric processes inside the skull. These can be large bruises, trauma and swelling.
2) The second mechanism of development is blockade of the outflow of cerebrospinal fluid from the brain cavities for various reasons (hemorrhage, meningitis).
3) The third mechanism for the accumulation of a large amount of cerebrospinal fluid is associated with a violation of its circulation and absorption, which can be caused by hemorrhages, brain damage, adhesions after brain surgery, and inflammatory diseases.
Manifestations of hydrocephalus in children
The manifestations of hydrocephalus in infancy practically do not depend on the cause of its occurrence.
When examining a baby, you can find the following signs:
- Head circumference is growing faster than the allowable rate. Normally, in infants, the head circumference increases by 1.5 cm every month. In a child with hydrocephalus, growth rates are faster than normal and a disproportionately large head attracts attention.
- The bones of the skull have become thinner. During the neonatal period, they are soft and pliable. Under the pressure of excess cerebrospinal fluid, the head grows, and the bones become thinner.
- The seams between the bones of the skull gape. The fact is that the skull of a newborn consists of several bones that are not fused with each other. The distance between them is called seams. As the child grows, the bones grow together and the seams close. With hydrocephalus, a large volume of cerebrospinal fluid does not allow the bones to grow together, pushing them apart.
- The forehead is disproportionately enlarged and overhangs the eyebrows. An enlarged forehead stands out against the background of the large size of the head.
- Protruding tense large fontanelle.
- Veins of the head are dilated. This is manifested by an increase in the venous pattern, clearly visible through the thin scalp.
In addition to the characteristic appearance (large head), other manifestations of the disease may be present.
These include disorders of the nervous system:
- Nausea, vomiting, severe anxiety, seizures, decreased appetite, or refusal to eat.
- Increased tone of the muscles of the extensors of the arms and legs, impaired swallowing, divergent squint, drooping eyelids, rolling eyes, paresis of various parts of the body, tremors (tremors) of the chin and limbs.
- Disturbances from other organs and systems, such as malfunctioning of the heart.
For children over the age of two, a characteristic manifestation of hydrocephalus is a lag in psychomotor development and disturbances on the part of the organ of vision. The following symptoms are also observed:
- Gait disorder, hyperkinesis (twitching), lower spastic paraparesis.
- Children are stunted or, conversely, are excessively tall. They may have premature maturation of the reproductive system, they may suffer from hypothyroidism and diabetes insipidus. All these violations are associated with abnormalities in the endocrine system.
- Such children often suffer from intellect, they are emotionally unstable.
- They are often disturbed by headaches in the morning, nausea and vomiting on an empty stomach may occur, physical activity is reduced, children are inactive, which is not typical for healthy children at this age.
- Violations of the organ of vision are most often manifested by double vision, but complete blindness can also occur.
- Children attending school have memory impairments, problems with academic performance, and they also poorly adapt to the new team.
Diagnostics and methods of detecting hydrocephalus
There are several methods for detecting the disease. Basically, in children, hydrocephalus is detected by a pediatrician at the next scheduled examination. Noticing signs of hydrocephalus, the pediatrician can refer the child to a neurologist for consultation, who, in turn, will prescribe an additional examination to clarify the diagnosis.
Additional examination methods include neurosonography (ultrasound), craniographic studies, determination of intracranial pressure, CT and MRI.
- Neurosonography is the only primary diagnostic method that allows you to assess the state of intracranial structures and observe changes in the ventricles and spaces between the meninges in real time. This method is used in both the fetus and the newborn, as well as in older children.
- Craniographic studies make it possible to assess the condition of the cranial sutures, to identify features in the structure of bones, to study the base of the skull and cranial fossa, and to identify local changes.
In this case, the following signs of hypertensive (with increased cerebrospinal fluid pressure) hydrocephalus can be detected:
- Divergence of the seams of the skull.
- The bones of the skull are thinned.
- The pattern of digital impressions (depressions in the bones of the skull resembling a trace from the fingertip) is enhanced.
- The Turkish saddle (one of the structures of the brain) is increased in size.
- Strengthened pneumatization (airiness) of the paranasal sinuses.
- The sizes of the cerebral section of the skull prevail over the facial ones.
- Since the vessels of the eyes are directly connected with the vessels of the brain, ophthalmoscopy is used to determine the state of intracranial pressure.
If intracranial pressure is increased, blood flows through the veins of the fundus with difficulty, and blood stagnation forms. At the same time, the discs of the optic nerves swell, small hemorrhages appear in the retina. When disc edema persists for a long time, vision decreases, irreversible changes may occur, leading to blindness.
Therefore, if a neurologist or pediatrician directs your baby to an ophthalmologist, do not be surprised, but be sure to undergo an examination. Examination of it will help to understand the changes taking place in the head.
- Computed tomography (CT) is the main diagnostic screening method. It is also used to assess the dynamics of the pathological process. With the help of the study, the ventricles of the brain and other intracranial spaces are assessed, determining the size, location, and presence of deformities. This examination allows you to reliably detect whether a child has hydrocephalus and determine its type. Based on this, further treatment tactics are built.
- The gold standard for diagnosing hydrocephalus in children is MRI.
With the help of MRI, one can determine the shape and severity of the disease, see the changes that have occurred in the ventricles and other intracranial spaces, the cause of the pathological condition, and many other important factors that help doctors determine the further tactics of treating the child.
Hydrocephalus treatment methods
In most patients, hydrocephalus progresses if left untreated and ends in severe, life-threatening complications or death. In infants, the main complication is delayed maturation of brain cells or complete cessation of maturation of brain structures. The consequence of this is a lag or delay in neuropsychic and intellectual development.
Hydrocephalus treatment methods initially depend on the cause of its occurrence. The main goal is to reduce the amount of cerebrospinal fluid in the cranial cavity.
There are two main treatments:
1) Conservative treatment without surgery.
This is a complex treatment with the appointment of diuretics (diuretics), which reduce intracranial pressure. Among diuretics, the preference is given to the drug Diacarb. Treatment aimed at eliminating the bacterial inflammation that caused the hydrocephalus includes the additional prescription of antibiotics. Such treatment is possible only with a mild form of hydrocephalus. If the process progresses, surgical treatment is used.
2) Surgical treatment.
If there is no threat to the child's life, then bypass surgery is performed routinely. While the little patient is waiting for his turn, a spinal tap is performed to temporarily reduce the pressure of the cerebrospinal fluid.
Hydrocephalus, which is a symptom of another disease, requires only observation. Hydrocephalus as an independent disease is treated surgically.
With a closed form of hydrocephalus, emergency intervention is often required, since there is a threat of respiratory arrest due to compression of the respiratory center.In such cases, they resort to surgery, establish a temporary reservoir in which the cerebrospinal fluid is collected. A closed form of hydrocephalus of any origin and a hypertensive form with impaired absorption of cerebrospinal fluid are also treated surgically, because conservative treatment has a short-term effect.
The main task of the surgeon is to remove the obstacle that interferes with the movement of the cerebrospinal fluid. If a tumor or cyst is an obstacle, it must be removed.
When the obstruction cannot be removed, surgical treatment is aimed at creating workarounds for the outflow of cerebrospinal fluid, the so-called shunts. A shunt is a system of tubules located under the skin that transport CSF to other cavities outside the head. Most often, the place of flow of cerebrospinal fluid is the abdominal cavity or the vascular bed, as well as the right atrium. Other body cavities as a reservoir of cerebrospinal fluid are used quite rarely, only when it is impossible to use standard methods.
Modern techniques have many shunting options, which are constantly being improved. Today, ventriculoperitoneal (from the ventricles to the abdominal cavity) shunting is most often performed. The shunt is a silicone valve system that helps regulate the pressure of the cerebrospinal fluid in the cavities. Surgery on children may require lengthening or replacing the system due to the child's growth.
The development of endoscopy has led to the creation of new methods of surgical treatment using endoscopic equipment.
The goal of endoscopic surgery is to create an anastomosis (connection) between the cavity of the third ventricle and the basal cisterns (the second largest cavity of the brain, which is a reservoir for cerebrospinal fluid) located at the base of the skull. Such an operation is appropriate for violations of the outflow in the posterior cranial fossa or in the area of the aqueduct of the brain.
Also, endoscopic operations are widely used when it is required to remove any obstacle to the movement of the cerebrospinal fluid, for example, to remove a cyst.
Without exception, all operations are aimed at restoring the balance between the production and elimination of cerebrospinal fluid.
Complications after bypass surgery
After the shunt is performed, the shunt may malfunction due to insufficient or excessive shunt discharge.
The causes of shunt dysfunction are:
- The valve is under pressure and does not open.
- The shunt becomes clogged with blood clots, slips out of the abdominal cavity, moves, twists. In this case, a mechanical obstacle is formed to drain the cerebrospinal fluid. Blockage can occur throughout the shunt, in any part of it.
With poor performance of the drainage system, a relapse of hydrocephalus occurs. The more the patient depends on the shunt and the higher the degree of malfunction, the more pronounced the manifestations of recurrent hydrocephalus. In some patients, the condition quickly deteriorates and they may fall into a coma, while others only occasionally experience headaches and discomfort.
Every third patient has a risk of recurrent violations after checking the shunt in the first year of life.
Increased shunt discharge (hyperdrainage) is first manifested by a decrease in intracranial pressure. In this case, the patient experiences headaches, nausea, turns pale and becomes covered with cold sweat when trying to get up. All of these signs are aggravated when the patient is in an upright position. Gradually, patients adjust and the complaints disappear, but in some cases surgery may be required.
Complications after bypass surgery occur in 47% of cases. They are classified into early and late. The early ones are manifested by inflammation, and the late ones - by the formation of adhesions.
Bacterial meningitis, as a complication, occurs in 10% of cases, and more often in premature babies. In addition, endocarditis and glomerulonephritis may develop.
If infected, the shunt is removed and antibiotics are given.
After endoscopic surgery, the complication rate is 5-9%.
Memo for parents
An emergency consultation with a neurosurgeon is required in the following cases:
- If the child is restless, drowsy, very often spits up, complains of a headache, throws his head back, vomits, convulsions appear, the fontanelle bulges out, the venous pattern on the head is enhanced.
- If the above signs are present with and without a high temperature.
- If CSF appears along the shunt, in the pump area or on the anterior abdominal wall.
- If there are signs of inflammation along the shunt (redness and induration).
- If you cannot pump the pump.
The sooner hydrocephalus is diagnosed and treatment is started, the better the prognosis. Thanks to modern medical advances, a child with timely treatment of hydrocephalus lives a normal life, despite the fact that sometimes there are problems in servicing the shunt.
Long-term untreated hydrocephalus irreversibly changes the brain, the child lags behind in development from peers and may become disabled. To avoid this, it is imperative to undergo all routine examinations and tests, as well as an additional examination prescribed by a doctor in case of suspicion of a disease.
Neurosonography is used to prevent hydrocephalus. This is a mandatory examination of all newborns, but especially premature babies, which is carried out in the first day of life in order to exclude malformations and hemorrhages inside the ventricles of the brain, which can cause the development of hydrocephalus.
