Movement of cerebrospinal fluid. Liquor (cerebrospinal fluid). How many ventricles does a person have and their structure

The human brain is made up of an amazing number of neurons - about 25 billion of them, and this is not the limit. Neuronal cell bodies are collectively called gray matter because they have a gray tint.

The arachnoid membrane protects the cerebrospinal fluid circulating inside it. It acts as a shock absorber that will protect the organ from impact.

The brain mass of a man is higher than that of a woman. However, the opinion that a woman’s brain is inferior in development to a man’s is erroneous. The average weight of the male brain is about 1375 g, the female brain is about 1245 g, which is 2% of the weight of the entire body. By the way, brain weight and human intelligence are not interrelated. If, for example, you weigh the brain of a person suffering from hydrocephalus, it will be larger than usual. At the same time, mental abilities are significantly lower.

The brain consists of neurons - cells capable of receiving and transmitting bioelectric impulses. They are supplemented by glia, which help neurons function.

The ventricles of the brain are cavities inside the brain. It is the lateral ventricles of the brain that produce cerebrospinal fluid. If the lateral ventricles of the brain are impaired, hydrocephalus may develop.

How does the brain work?

Before moving on to considering the functions of the ventricles, let us recall the location of some parts of the brain and their significance for the body. This will make it easier to understand how this whole complex system works.

The brain is finite

It is impossible to briefly describe the structure of such a complex and important organ. The telencephalon runs from the back of the head to the forehead. It consists of large hemispheres - right and left. It has many grooves and convolutions. The structure of this organ is closely related to its development.

Conscious human activity is associated with the functioning of the cerebral cortex. Scientists distinguish three types of bark:

Ancient.
The old one.
New one. The rest of the cortex, which was the last to develop during human evolution.

Hemispheres and their structure

The hemispheres are a complex system that consists of several levels. They have different parts:

frontal;
parietal;
temporal;
occipital

In addition to the lobes, there is also a cortex and subcortex. The hemispheres work together, they complement each other, performing a set of tasks. There is an interesting pattern - each part of the hemispheres is responsible for its own functions.

Bark

It is difficult to imagine that the cortex, which provides the main characteristics of consciousness and intelligence, is only 3 mm thick. This thinnest layer reliably covers both hemispheres. It is composed of the same nerve cells and their processes, which are located vertically.

The layering of the crust is horizontal. It consists of 6 layers. The cortex contains many vertical nerve bundles with long processes. There are more than 10 billion nerve cells here.

The cortex is assigned various functions that are differentiated between its different sections:

temporal – smell, hearing;
occipital – vision;
parietal – taste, touch;
frontal – complex thinking, movement, speech.

It affects the brain structure. Each of its neurons (we remind you that there are about 25 billion of them in this organ) creates about 10 thousand connections with other neurons.

In the hemispheres themselves there are basal ganglia - these are large clusters that consist of gray matter. It is the basal ganglia that transmit information. Between the cortex and the basal ganglia are the processes of neurons - the white matter.

It is the nerve fibers that form the white matter; they connect the cortex and those formations that are under it. The subcortex contains the subcortical nuclei.

The telencephalon is responsible for physiological processes in the body, as well as intelligence.

Intermediate brain

It consists of 2 parts:

ventral (hypothalamus);
dorsal (metathalamus, thalamus, epithalamus).

It is the thalamus that receives stimuli and sends them to the hemispheres. This is a reliable and always busy intermediary. Its second name is the visual thalamus. The thalamus ensures successful adaptation to an ever-changing environment. The limbic system reliably connects it to the cerebellum.

The hypothalamus is a subcortical center that regulates all autonomic functions. It affects through the nervous system and glands. The hypothalamus ensures the normal functioning of individual endocrine glands and participates in metabolism, which is so important for the body. The hypothalamus is responsible for the processes of sleep and wakefulness, eating and drinking.

Below it is the pituitary gland. It is the pituitary gland that provides thermoregulation, the functioning of the cardiovascular and digestive systems.

hindbrain

It consists of:

front axle;
the cerebellum behind it.

The bridge visually resembles a thick white cushion. It consists of a dorsal surface, which is covered by the cerebellum, and a ventral surface, the structure of which is fibrous. The bridge is located above the medulla oblongata.

Cerebellum

It is often called the second brain. This department is located behind the bridge. It covers almost the entire surface of the posterior cranial fossa.

The large hemispheres hang directly above it, separated only by a transverse gap. Below, the cerebellum is adjacent to the medulla oblongata. There are 2 hemispheres, the lower and upper surface, the worm.

The cerebellum has many slits along its entire surface, between which one can find convolutions (ridges of the medulla).

The cerebellum consists of two types of substance:

Gray. It is located on the periphery and forms the cortex.
White. It is located in the area under the bark.

The white matter penetrates into all convolutions, literally penetrating them. It can be easily recognized by its characteristic white stripes. In the white matter there are inclusions of gray - the nucleus. Their interweaving in cross-section visually resembles an ordinary branched tree. It is the cerebellum that is responsible for coordinating movements.

Midbrain

It is located from the anterior region of the bridge to the optic tracts and papillary bodies. There are many nuclei (tubercles of the quadrigeminal). The midbrain is responsible for the functioning of latent vision and the orienting reflex (it ensures that the body turns to where the noise is heard).

Ventricles

The ventricles of the brain are cavities connected to the subarachnoid space, as well as the spinal cord canal. If you're wondering where cerebrospinal fluid is produced and stored, it happens in the ventricles. Inside they are covered with ependyma.

Ependyma is a membrane that lines the surface of the ventricles from the inside. It can also be found inside the spinal canal and all cavities of the central nervous system.

Types of ventricles

Ventricles are divided into the following types:

Lateral. Inside these large cavities there is cerebrospinal fluid. The lateral ventricle of the brain is large in size. This is explained by the fact that quite a lot of fluid is produced, because not only the brain, but also the spinal cord needs it. The left ventricle of the brain is called the first, the right - the second. The lateral ventricles communicate with the third ventricle through foramina. They are symmetrically located. From each lateral ventricle departs the anterior horn, the posterior horns of the lateral ventricles, the lower, and the body.
Third. Its location is between the visual tuberosities. It has the shape of a ring. The walls of the third ventricle are filled with gray matter. There are many autonomic subcortical centers here. The third ventricle communicates with the midbrain and lateral ventricles.
Fourth. Its location is between the cerebellum and the medulla oblongata. This is the remnant of the cavity of the brain bladder, which is located behind. The shape of the fourth ventricle resembles a tent with a roof and a bottom. Its bottom is diamond-shaped, which is why it is sometimes called a diamond-shaped fossa. The spinal cord canal opens into this fossa from behind.

The shape of the lateral ventricles resembles the letter C. They synthesize cerebrospinal fluid, which must then circulate in the spinal cord and brain.

If the cerebrospinal fluid does not drain correctly from the ventricles, the person may be diagnosed with hydrocephalus. In severe cases, it is noticeable even in the anatomical structure of the skull, which is deformed due to strong internal pressure. Excess liquid tightly fills the entire space. It can change the functioning of not only the ventricles, but also the entire brain. Excessive amounts of cerebrospinal fluid can cause a stroke.

Diseases

The ventricles are susceptible to a number of diseases. The most common among them is the above-mentioned hydrocephalus. With this disease, the cerebral ventricles can grow to pathologically large sizes. In this case, the head hurts, a feeling of pressure appears, coordination may be impaired, nausea and vomiting appear. In severe cases, it is difficult for a person to even move. This can lead to disability and even death.

The appearance of the mentioned signs may indicate congenital or acquired hydrocephalus. Its consequences are detrimental to the brain and the body as a whole. Blood circulation may be impaired due to constant compression of soft tissues, and there is a risk of hemorrhage.

The doctor must determine the cause of hydrocephalus. It can be congenital or acquired. The latter type occurs with a tumor, injury, etc. All departments suffer. It is important to understand that the development of pathology will gradually worsen the patient’s condition, and irreversible changes will occur in the nerve fibers.

The symptoms of this pathology are associated with the fact that more cerebrospinal fluid is produced than necessary. This substance quickly accumulates in the cavities, and since there is a decrease in outflow, the cerebrospinal fluid does not drain away as it should normally. The accumulated cerebrospinal fluid can be in the ventricles and stretch them, it compresses the vascular walls, impairing blood circulation. Neurons do not receive nutrition and quickly die. It is impossible to restore them later.

Hydrocephalus often affects newborns, but it can appear at almost any age, although it is much less common in adults. Proper circulation of cerebrospinal fluid can be established with proper treatment. The only exception is severe congenital cases. During pregnancy, ultrasound can reveal possible hydrocephalus in the baby.

If during pregnancy a woman indulges in bad habits and does not follow proper nutrition, this entails an increased risk of fetal hydrocephalus. Asymmetric development of the ventricles is also possible.

To diagnose pathologies in the functioning of the ventricles, MRI and CT are used. These methods help to identify abnormal processes at a very early stage. With adequate treatment, the patient's condition can improve. Even a complete recovery is possible.

Quite often, after birth, babies have enlarged ventricles of the brain. This condition does not always mean the presence of a disease that necessarily requires treatment.

Ventricular system of the brain

The ventricles of the brain are several interconnected collectors in which the formation and distribution of liquor fluid occurs. Liquor washes the brain and spinal cord. Normally, there is always a certain amount of cerebrospinal fluid in the ventricles.

Two large collectors of cerebrospinal fluid are located on either side of the corpus callosum. Both ventricles are connected to each other. On the left side is the first ventricle, and on the right is the second. They consist of horns and a body. The lateral ventricles are connected through a system of small holes to the 3rd ventricle.

In the distal part of the brain, between the cerebellum and the medulla oblongata, there is the 4th ventricle. It is quite large in size. The fourth ventricle is diamond-shaped. At the very bottom there is a hole called the diamond-shaped fossa.

Proper functioning of the ventricles allows cerebrospinal fluid to enter the subarachnoid space when necessary. This zone is located between the dura mater and the arachnoid membrane of the brain. This ability allows you to maintain the required volume of cerebrospinal fluid in various pathological conditions.

In newborn babies, dilatation of the lateral ventricles is often observed. In this condition, the horns of the ventricles are enlarged, and increased accumulation of fluid in the area of their bodies may also be observed. This condition often causes both left and right ventricle enlargement. In differential diagnosis, asymmetry in the area of the main brain collectors is excluded.

The size of the ventricles is normal

In infants, the ventricles are often dilated. This condition does not at all mean that the child is seriously ill. The dimensions of each ventricle have specific values. These indicators are shown in the table.

To assess normal indicators, the determination of all structural elements of the lateral ventricles is also used. The lateral cisterns should be less than 4 mm deep, the anterior horns between 2 and 4 mm, and the occipital horns between 10 and 15 mm.

Causes of enlarged ventricles

Premature babies may have dilated ventricles immediately after birth. They are located symmetrically. Symptoms of intracranial hypertension in a child with this condition usually do not occur. If only one of the horns increases slightly, then this may be evidence of the presence of pathology.

The following reasons lead to the development of ventricular enlargement:

Fetal hypoxia, anatomical defects in the structure of the placenta, development of placental insufficiency. Such conditions lead to disruption of the blood supply to the brain of the unborn child, which can cause expansion of the intracranial collectors.

Traumatic brain injuries or falls. In this case, the outflow of cerebrospinal fluid is disrupted. This condition causes water to stagnate in the ventricles, which can lead to symptoms of increased intracranial pressure.

Pathological birth. Traumatic injuries, as well as unforeseen circumstances during childbirth, can lead to disruption of the blood supply to the brain. These emergency conditions often contribute to the development of ventricular dilatation.

Infection with bacterial infections during pregnancy. Pathogenic microorganisms easily penetrate the placenta and can cause various complications in the child.

Prolonged labor. Too long a time between the rupture of amniotic fluid and the expulsion of the baby can lead to the development of intrapartum hypoxia, which causes a disruption in the outflow of cerebrospinal fluid from the dilated ventricles.

Oncological formations and cysts that are located in the brain. The growth of tumors puts excess pressure on intracerebral structures. This leads to the development of pathological expansion of the ventricles.

Foreign bodies and elements which are located in the brain.

Infectious diseases. Many bacteria and viruses easily penetrate the blood-brain barrier. This contributes to the development of numerous pathological formations in the brain.

How does it manifest?

Ventricular dilatation does not always lead to adverse symptoms. In most cases, the child does not experience any discomfort that would indicate the presence of a pathological process.

Only with pronounced disturbances do the first adverse manifestations of the disease begin to occur. These include:

Gait disturbance. Babies begin to walk on tiptoes or step on their heels.

The appearance of visual disturbances. They often manifest themselves in children in the form of squint or insufficient focusing on various objects. In some cases, a child may experience double vision, which worsens when looking at small objects.

Trembling of hands and feet.

Behavioral disorders. Babies become more lethargic and drowsy. In some cases, even apathetic. It is very difficult to captivate a child with any games or recreational activities.

Headache. It appears when intracranial pressure increases. At the height of pain, vomiting may occur.

Dizziness.

Decreased appetite. Babies in the first months of life refuse to breastfeed and eat poorly. In some cases, the baby spits up more.

Sleep disturbance. Babies may have difficulty falling asleep. Some children walk in their sleep.

The disease can vary in severity. With minimal symptoms, they speak of a mild course. When headache, dizziness, and other symptoms indicating high intracranial hypertension appear, the disease becomes moderately severe. If the child’s general condition is severely disturbed and treatment in a hospital setting is required, then the disease becomes more severe.

Consequences

Late diagnosis of pathological conditions that lead to the appearance of enlargements in the area of the ventricles of the brain can affect the further development of the child. The first persistent symptoms of ventricular dilatation are observed in babies at 6 months.

Impaired outflow of liquor fluid can lead to a persistent increase in intracranial pressure. In severe cases of the disease, this contributes to the development of disturbances of consciousness. Visual and hearing disorders lead to the development of hearing loss and weakened vision in the child. Some children experience epileptic seizures and seizures.

Diagnostics

In order to determine the exact size of the ventricles, as well as find out their depth, doctors prescribe several examination methods.

The most informative and reliable are:

Ultrasonography. Allows you to accurately describe the quantitative indicators of the ventricles, as well as calculate the ventricular index. Using ultrasound, you can estimate the volume of liquor fluid that is present in the brain collectors during the study.

CT scan. With high accuracy it allows you to describe the structure and size of all ventricles of the brain. The procedure is safe and does not cause pain in the baby.

Magnetic resonance imaging. It is used in complex diagnostic cases when establishing a diagnosis is difficult. Suitable for older children who are able to remain still throughout the examination. In young children, MRI is performed under general anesthesia.

Fundus examination.

Neurosonography.

Treatment

Treatment of pathological conditions that lead to dilatation and asymmetry of the ventricles of the brain is usually carried out by a neurologist. In some cases, when the cause of the disease is space-occupying formations or the consequences of traumatic brain injuries, a neurosurgeon is involved.

To eliminate pathological symptoms, the following treatment methods are used:

Prescribing diuretics. Diuretics help reduce the manifestations of intracranial hypertension and improve the baby’s well-being. They also help normalize the formation of cerebrospinal fluid.

Nootropics. They improve brain function and also promote good blood supply to blood vessels.

Medicines with a sedative effect. Used to eliminate increased anxiety and agitation.

Potassium preparations. Positively affects urine excretion. This helps reduce the increased amount of cerebrospinal fluid in the body.

Multivitamin complexes. They are used to compensate for all the necessary microelements involved in vital processes. They also help strengthen the body and promote better resistance to disease.

Soothing and relaxing massage. Allows you to reduce muscle tone and also helps to relax the nervous system.

Physiotherapy. Helps normalize the outflow of liquor fluid and prevents its stagnation in the cerebral ventricles.

Prescribing antibacterial or antiviral drugs according to indications. They are used only in cases where the cause of the disease is viruses or bacteria. Appointed for a course appointment.

Surgery. It is used in the presence of various space-occupying formations or to remove fragments of bone tissue as a result of a skull fracture due to traumatic brain injury.

Forecast

If the condition develops in infancy and early infancy, the course of the disease is usually favorable. With appropriate treatment, all discomfort symptoms quickly disappear and do not bother the baby. High intracranial pressure is normalized.

In older children, the prognosis of the disease is somewhat different. Adverse symptoms are much more difficult to treat. A long course of the disease can lead to permanent visual and hearing impairment. If treatment was not started in a timely manner, then in most cases the child experiences persistent disorders that negatively affect his mental and mental development.

Dr. Komarovsky will talk about the expansion of the ventricles of the brain in infants and its consequences.

The most common complaint that a doctor hears from his patients is that both adults and children complain about it. It is impossible to ignore this. Especially if there are other symptoms. Parents should pay special attention to the child’s headaches and the baby’s behavior, because he cannot say that he is in pain. Perhaps these are the consequences of a difficult birth or congenital anomalies, which can be determined at an early age. Maybe these are liquorodynamic disturbances. What is it, what are the characteristic signs of this disease in children and adults and how to treat it, we will consider further.

What does liquorodynamic disturbances mean?

Liquor is cerebrospinal fluid that constantly circulates in the ventricles, cerebrospinal fluid ducts and in the subarachnoid space of the brain and spinal cord. Liquor plays an important role in metabolic processes in the central nervous system, in maintaining homeostasis in brain tissue, and also creates a certain mechanical protection for the brain.

Liquorodynamic disorders are conditions in which the circulation of cerebrospinal fluid is disrupted, its secretion and reverse processes are regulated by glands that are located in the choroid plexuses of the ventricles of the brain that produce fluid.

In the normal state of the body, the composition of the cerebrospinal fluid and its pressure are stable.

What is the mechanism of violations

Let's consider how liquorodynamic disorders of the brain can develop:

The rate of production and release of cerebrospinal fluid by the choroid plexuses increases.
The rate of absorption of cerebrospinal fluid from the subarachnoid space slows down due to the blocking of the narrowing of the cerebrospinal fluid vessels due to previous subarachnoid hemorrhages or inflammatory
The rate of CSF production decreases during the normal absorption process.

The rate of absorption, production and release of cerebrospinal fluid is influenced by:

On the state of cerebral hemodynamics.
State of the blood-brain barrier.

The inflammatory process in the brain increases its volume and increases intracranial pressure. The result is poor circulation and blockage of the vessels through which the cerebrospinal fluid moves. Due to the accumulation of fluid in the cavities, partial death of intracranial tissue may begin, and this will lead to the development of hydrocephalus.

Classification of violations

Liquorodynamic disorders are classified in the following areas:

How does the pathological process proceed:

Chronic course.
Acute phase.

2. Stages of development:

Progressive. Intracranial pressure increases and pathological processes progress.
Compensated. Intracranial pressure is stable, but the ventricles of the brain remain dilated.
Subcompensated. Great danger of crises. Unstable condition. Blood pressure can rise sharply at any moment.

3. In which cavity of the brain is the cerebrospinal fluid located:

Intraventricular. Fluid accumulates in the ventricular system of the brain due to obstruction of the cerebrospinal fluid system.
Subarachnoid. Liquorodynamic disturbances of the external type can lead to destructive lesions of brain tissue.
Mixed.

4. Depending on the pressure of the cerebrospinal fluid:

Hypertension. Characterized by high intracranial pressure. The outflow of cerebrospinal fluid is impaired.
Normotensive stage. Intracranial pressure is normal, but the ventricular cavity is enlarged. This condition is most common in childhood.
Hypotension. After surgery, excessive outflow of cerebrospinal fluid from the ventricular cavities.

Causes congenital

There are congenital anomalies that can contribute to the development of liquorodynamic disorders:

Genetic disorders in
Agenesis of the corpus callosum.
Dandy-Walker syndrome.
Arnold-Chiari syndrome.
Encephalocele.
Stenosis of the cerebral aqueduct, primary or secondary.
Porencephalic cysts.

Acquired reasons

Liquorodynamic disorders can begin to develop for acquired reasons:

Symptoms of liquorodynamic disorders in adults

Liquorodynamic disorders of the brain in adults are accompanied by the following symptoms:

Severe headaches.
Nausea and vomiting.
Fast fatiguability.
Horizontal eyeballs.
Increased tone, muscle stiffness.
Cramps. Myoclonic seizures.
Speech impairment. Intellectual problems.

Symptoms of disorders in infants

Liquorodynamic disorders in children under one year of age have the following symptoms:

Frequent and profuse regurgitation.
Unexpected crying for no apparent reason.
Slow overgrowth of the fontanel.
Monotonous crying.
The child is lethargic and sleepy.
Sleep is disturbed.
Seams coming apart.

Over time, the disease progresses more and more, and signs of liquorodynamic disorders become more pronounced:

Tremor of the chin.
Twitching of limbs.
Involuntary shudders.
Life support functions are disrupted.
Disturbances in the functioning of internal organs for no apparent reason.
Possible squint.

Visually, you can notice the vascular network in the area of the nose, neck, and chest. When crying or tense muscles, it becomes more pronounced.

The neurologist may also note the following signs:

Hemiplegia.
Extensor hypertonicity.
Meningeal signs.
Paralysis and paresis.
Paraplegia.
Graefe's symptom.
Nystagmus is horizontal.
Delay in psychomotor development.

You should visit your pediatrician regularly. At the appointment, the doctor measures the volume of the head, and if pathology develops, changes will be noticeable. So, there may be such deviations in the development of the skull:

The head grows quickly.
It has an unnaturally elongated shape.
Large and swell and pulsate.
Sutures are coming apart due to high intracranial pressure.

All these are signs that a syndrome of liquorodynamic disorders is developing in an infant. Hydrocephalus progresses.

I would like to note that it is difficult to determine liquorodynamic crises in infants.

Signs of liquorodynamic disorders in children after one year

After one year, a child’s skull is already formed. The fontanelles have completely closed and the sutures have ossified. If there are liquorodynamic disturbances in a child, signs of increased intracranial pressure appear.

There may be such complaints:

Headache.
Apathy.
Worry for no reason.
Nausea.
Vomiting, after which there is no relief.

The following signs are also characteristic:

Gait and speech are impaired.
There are disturbances in the coordination of movements.
Vision decreases.
Horizontal nystagmus.
In advanced cases, “bobble doll head”.

And also, if liquorodynamic disorders of the brain progress, the following deviations will be noticeable:

The child speaks poorly.
They use standard, memorized phrases without understanding their meaning.
Always in a good mood.
Delayed sexual development.
Convulsive syndrome develops.
Obesity.
Disturbances in the functioning of the endocrine system.
Lag in the educational process.

Diagnosis of the disease in children

In children under one year of age, diagnosis first of all begins with interviewing the mother and collecting information about how pregnancy and childbirth went. Next, complaints and observations from parents are taken into account. Then the child needs to be examined by the following specialists:

Neurologist.
Ophthalmologist.

To clarify the diagnosis, you will need to undergo the following studies:

CT scan.
Neurosonography.

Diagnosis of the disease in adults

If you experience headaches and the symptoms described above, you should consult a neurologist. To clarify the diagnosis and prescribe treatment, the following studies may be prescribed:

Computed tomography.
Angiography.
Pneumoencephalography.
brain
NMRI.

If there is a suspicion of a syndrome of cerebrospinal fluid dynamics disorders, a lumbar puncture may be prescribed with a change in cerebrospinal fluid pressure.

When diagnosing adults, much attention is paid to the underlying disease.

Treatment of liquorodynamic disorders

The earlier the disease is detected, the greater the chance of restoring lost brain functions. The type of treatment is selected based on the presence of pathological changes in the course of the disease, as well as the age of the patient.

In the presence of increased intracranial pressure, diuretics are usually prescribed: Furosemide, Diacarb. Antibacterial agents are used in the treatment of infectious processes. Normalization of intracranial pressure and its treatment is the main task.

To relieve swelling and inflammation, glucocorticoid drugs are used: Prednisolone, Dexamethasone.

Steroid medications are also used to reduce cerebral edema. It is necessary to eliminate the cause of the disease.

As soon as liquorodynamic disturbances are detected, treatment should be prescribed immediately. After undergoing complex therapy, positive results are noticeable. This is especially important during the period of child development. Speech improves, progress in psychomotor development is noticeable.

Surgical treatment is also possible. It may be prescribed in the following cases:

Drug treatment is ineffective.
Liquorodynamic crisis.
Occlusive hydrocephalus.

Surgical treatment is considered for each case of the disease separately, taking into account age, characteristics of the body and the course of the disease. In most cases, surgery on the brain is avoided so as not to damage healthy brain tissue, and complex drug treatment is used.

It is known that if the syndrome of liquorodynamic disorders in a child is not treated, the mortality rate is 50% up to 3 years, 20-30% of children survive to adulthood. After surgery, mortality is 5-15% of sick children.

Mortality increases due to late diagnosis.

Prevention of liquorodynamic disorders

Preventive measures include:

Observation of pregnancy in the antenatal clinic. It is very important to register as early as possible.
Timely detection of intrauterine infections and their treatment.

At 18-20 weeks, an ultrasound shows the development of the fetal brain and the state of the unborn child’s cerebrospinal fluid. At this time, it is possible to determine the presence or absence of pathologies.

The right choice of delivery.
Regular monitoring by a pediatrician. Measuring the circumference of the skull, if there is a need to conduct a fundus examination.
If the fontanel does not close in a timely manner, it is necessary to conduct neurosonography and consult a neurosurgeon.
Timely removal of tumors that block the cerebrospinal fluid pathways.
Regular observation by a doctor and carrying out the necessary studies after suffering injuries to the brain and spinal cord.
Timely treatment of infectious diseases.
Prevention and therapy of chronic diseases.
Quit smoking and alcohol.
It is recommended to play sports and lead an active lifestyle.

It is easier to prevent any disease or take all measures to reduce the risk of developing pathology. If liquorodynamic disorders are diagnosed, then the earlier therapy is started, the greater the chance that the child will develop normally.

The brain is a closed system of the body that needs protection from the external environment. The main barrier is the bones of the skull, under which several layers of shells are hidden. Their function is to create a buffer zone between the inside of the skull and the brain itself.

In addition, between the 2nd and 3rd membranes there is a functional cavity - the subarachnoid or subarachnoid space, in which cerebrospinal fluid - cerebrospinal fluid - constantly circulates. With its help, the brain receives the necessary amount of nutrients and hormones, and also removes metabolic products and toxins.

The synthesis and control of the release of cerebrospinal fluid is carried out by the ventricles of the brain, which are an open system of cavities lined from the inside with a layer of functional cells.

Anatomically, the ventricular system of the brain is a collection of cisterns of brain sections through which cerebrospinal fluid circulates through the subarachnoid space and the central spinal canal. This process is carried out due to a thin layer of ependymocytes, which, with the help of cilia, provoke fluid movement and control the filling of the ventricular system. They also produce myelin, which serves as a sheath for the myelinated fibers of white matter.

The ventricles are also responsible for performing secretory and cleansing functions: the ependyma cavity lining them not only produces cerebrospinal fluid, but also filters it from metabolic products, toxic and medicinal substances.

How much cerebrospinal fluid the ventricles secrete and their size are influenced by many factors: the shape of the skull, the volume of the brain, the physical condition of the person and the presence of concomitant diseases of the central nervous system, for example, hydrocephalus or ventriculomegaly.

Experts have calculated that in a healthy person, the volume of cerebrospinal fluid released per hour is approximately 150-160 ml, and it is completely renewed after 7-8 hours. In total, the ventricular system secretes about 400-600 ml of cerebrospinal fluid per day, but this figure may vary depending on the blood pressure and psycho-emotional state of the person.

Modern methods of studying the structure of the brain make it possible to study its internal structures without resorting to direct opening of the skull. If a specialist needs to obtain information about the size of the child’s lateral ventricles, he will give a referral for neurosonography, a method of examining the brain using ultrasound equipment. If an examination is required for an adult, then he is given an MRI or CT scan of the relevant departments.

Table of norms for the size of structures of the ventricular system of an adult when examining the brain using X-ray computed tomography

Also, to assess the condition of the ventricular system of an adult, the condition index of each of its parts is calculated separately.

Table of indices of the IV ventricle, bodies and anterior horns of the lateral ventricles

How many ventricles does a person have, their structure and functions

The ventricular system of the brain consists of 4 cavities through which cerebrospinal fluid is produced and circulates between the structures of the central nervous system. Sometimes specialists, when examining the structures of the central nervous system, discover the 5th ventricle, which is not one - it is a slit-like hypoechoic expansion located in the midline of the brain. Such an abnormal structure of the ventricular system requires attention from doctors: often patients with a 5th ventricle are at increased risk of developing mental disorders.
Anatomically, the first and second ventricles are located in the lower part of the left and right hemispheres, respectively. Each of them is a C-shaped cavity located below the corpus callosum and encircling the posterior part of the cluster of nerve ganglia of the subcortical structures of the brain. Normally, the volume and, accordingly, the size of the lateral ventricle of an adult should not exceed 25 ml. These cavities do not communicate with each other, but each has a channel through which the cerebrospinal fluid enters the third ventricle.

The third ventricle has the shape of a ring, the walls of which are the thalamus and hypothalamus. In the brain, it is located between the optic thalamus, and in its center is the intermediate mass of the visual thalamus. Through the aqueduct of Sylvius it communicates with the cavity of the 4th ventricle, and through the interventricular foramina with the 1st and 2nd ventricles.

Topographically, the 4th ventricle is located between the structures of the posterior section and the so-called rhomboid fossa, the posteroinferior angle of which opens into the central canal of the spinal cord.

The structure of the internal layer of the structures of the ventricular system is also heterogeneous: in the first and second ventricles it is a single-layer ependymal membrane, and in the third and fourth there may be several layers of it.

The cytological composition of the ependyma is uniform throughout: it consists of specific neuroglial cells - ependymocytes. They are cylindrical cells, the free end of which is covered with cilia. With the help of vibration of the cilia, the flow of cerebrospinal fluid through the structures of the central nervous system is carried out.

Not so long ago, at the bottom of the third ventricle, experts discovered another type of ependymocyte - tanycytes, which differ from the previous ones in the absence of cilia and the ability to transmit data on the chemical composition of the cerebrospinal fluid to the capillaries of the pituitary portal system.

Lateral ventricles 1 and 2

Anatomically, the lateral or lateral ventricles of the brain consist of a body, anterior, posterior and inferior horn.

The central part of the lateral ventricle looks like a horizontal slit. Its upper wall is formed by the corpus callosum, and in the lower part there is the caudate nucleus, the dorsum of the thalamus and the posterior peduncle of the fornix. Inside the cavity of the lateral ventricles there is a choroid plexus, through which cerebrospinal fluid is synthesized.

Outwardly, it resembles a strip of dark red color 4 mm wide. From the central part, the choroid plexus is directed to the posterior horn, the upper wall of which is formed by the fibers of the large forceps of the corpus callosum, and the rest is the white matter of the occipital part of the telencephalon.

The inferior horn of the lateral ventricle is located in the temporal lobe and is directed downward, anterior and medial to the central line. On the side and above it is limited by the white matter of the temporal lobe; the medial wall and part of the lower one forms the hippocampus.

Anatomically, the anterior horn is a continuation of the body of the lateral cavity. It is directed laterally forward relative to the central cavity of the ventricle, and on the medial side it is limited by the wall of the transparent septum, and on the side by the head of the caudate nucleus. The remaining sides of the anterior horn form the fibers of the corpus callosum.

In addition to the main functions - synthesis and circulation of cerebrospinal fluid, the lateral ventricles are involved in the restoration of brain structures. Until recently, it was believed that nerve cells are not capable of renewal, but this is not entirely true: between the lateral ventricle and the olfactory bulb of one hemisphere there is a channel, inside which scientists have discovered an accumulation of stem cells. They are able to migrate inside the olfactory bulb and take part in restoring the number of neurons.

Physiometric indicators of the lateral ventricles (namely their size) can be taken in several ways. Thus, in children of the first year of life, examination is carried out using neurosonography (NSG), and in adults - using MRI or CT. Then the obtained data is processed and compared with standard indicators.

The lateral ventricles of the brain are normal in a child:

These indicators are taken into account when diagnosing brain pathologies, for example, hydrocephalus or hydrocephalus of the medulla - a disease that is characterized by increased secretion of cerebrospinal fluid and disruption of its outflow, which leads to increased pressure on the walls of the ventricles and expansion of their cavities.

To reduce the risk of developing pathology, the first examination of the child’s brain is carried out during his intrauterine development during screening examinations. This makes it possible to identify central nervous system diseases at an early stage. For example, during such a study, asymmetry of the lateral ventricles of the embryo may be detected. This approach allows specialists to prepare and immediately begin carrying out therapeutic measures immediately after the birth of the child.

3rd ventricle of the brain

Topographically, the third ventricle of the brain is located at the level of the intermediate section, between the visual thalamus, surrounding the intermediate mass of the visual thalamus with a ring. Has 6 walls:

Roof. It is formed by a strip of epithelium and a vascular tegmentum, which is a continuation of the pia mater, which serves as the basis of the choroid plexus of the 3rd ventricle. This structure penetrates the lateral cisterns through the interventricular foramina in the upper part, forming its own choroid plexus in them.
The surface of the visual tuberosities serves as the lateral walls, while the inner part of the ventricle is formed due to the germination of the intermediate mass.
The anterior upper wall is formed by the columns of the fornix of the brain and its white anterior commissure, and the lower wall is formed by the terminal gray plate, which is located between the columns of the fornix.
From the back, the third ventricle is limited by a commissure located above the opening of the entrance to the Sylvian aqueduct. At the same time, the rear part on top is formed by a pineal-shaped depression and a soldering of wires.
The bottom of the third ventricle is the base of the brain in the area of the posterior perforated substance, mastoid bodies, gray tubercle and optic chiasm.

The physiological significance of the third ventricle is that it is a cavity whose walls contain autonomic centers. For this reason, an increase in its volume and abnormal structure can cause deviations in the processes of excitation and inhibition of the autonomic nervous system, which is responsible for the physical condition of a person. For example, if the third ventricle of the brain is dilated, this affects the functioning of the structures of the circulatory, respiratory and endocrine systems.

Standards for the size of the third ventricle in a child:

4th ventricle of the brain

Anatomically, the fourth ventricle is located between the cerebellum, the posterior surface of the pons and the medulla oblongata, in the so-called rhomboid fossa. At the embryonic stage of child development, it is formed from the remains of the hindbrain vesicle, and therefore serves as a common cavity for all parts of the hindbrain.

Visually, the IV ventricle resembles a triangle, the bottom of which is the structures of the medulla oblongata and the pons, and the roof is the upper and lower velum. The superior velum is a thin membrane stretched between the superior cerebellar peduncles, and the inferior velum is adjacent to the peduncles of the cerebellum and is complemented by a plate of soft membrane, which forms the choroid plexus.

The functional purpose of the IV ventricle, in addition to producing and storing cerebrospinal fluid, is to redistribute its flow between the subarachnoid space and the central canal of the spinal cord. In addition, in the thickness of its bottom are located the nuclei of the V-XII cranial nerves, which are responsible for the work of the muscles of the corresponding muscles of the head, for example, oculomotor, facial, swallowing, etc.

5th ventricle of the brain

Sometimes in medical practice there are patients who have a V ventricle. Its presence is considered a structural feature of the ventricular system of an individual and is more of a pathology than a variant of the norm.

The walls of the fifth ventricle are formed by fusion of the internal parts of the membranes of the cerebral hemispheres, while its cavity does not communicate with other structures of the ventricular system. For this reason, it would be more correct to call the resulting niche the cavity of a “transparent partition”. Although the fifth ventricle does not have a choroid plexus, it is filled with cerebrospinal fluid, which enters through the pores of the septa.

The size of the V ventricle is strictly individual for each patient. In some, it is a closed and autonomous cavity, and sometimes in its upper part there is a gap up to 4.5 cm long.

Despite the fact that the existence of a cavity of the septum pellucidum is an anomaly in the structure of the adult brain, its presence is obligatory at the embryonic stage of fetal development. Moreover, in 85% of clinical cases it heals by the age of six months.

What diseases can affect the ventricles

Diseases of the ventricular system of the brain can be either congenital or acquired. Experts include hydrocephalus (water on the brain) and ventriculomegaly to the first type. These diseases are often the result of improper development of the child’s brain structures during the embryonic period due to a previous chromosomal malfunction or infection of the fetus with infections.

Hydrocephalus

Dropsy of the brain is characterized by improper functioning of the ventricular system of the head - excessive secretion of cerebrospinal fluid and its insufficient absorption into the bloodstream by the structures of the occipital-parietal zone. As a result, all cavities and the subarachnoid space are filled and, accordingly, put pressure on other structures, causing encephalopathic destruction of the brain.

In addition, due to increased intracranial pressure, the bones of the skull are displaced, which is visually expressed in an increase in head circumference. The strength of the manifestations of the symptomatic signs of hydrocephalus depends on how strong the deviation is in the system of production and absorption of cerebrospinal fluid: the more pronounced this discrepancy, the stronger the manifestations of the disease and the destruction of brain matter.

Sometimes, if untreated, the head grows so quickly that the patient cannot cope with its severity and remains bedridden for the rest of his life.

A person can get hydrocele at any age, but most often it occurs in children, being a congenital disease. In the adult population, pathology usually occurs due to a violation of the outflow of cerebrospinal fluid due to head trauma, infection of the meninges, the occurrence of a tumor and toxic poisoning of the body.

Clinical manifestations of hydrocephalus include the development of neurological disorders of varying severity in the patient and a change in the volume of the cranium, which is noticeable to the naked eye:

Since the bones of the head of a child in the first year of life are plastic, an increase in the amount of cerebrospinal fluid deforms it, which is visually expressed not only in an increase in the volume of the head due to the divergence of the seams of the bones of the cranial vault, but also in the enlargement of the frontal bone.

A child with hydrocephalus usually experiences swelling and bulging of the fontanelles due to increased intracranial pressure.

There are also other external signs of hydrocephalus:

lack of appetite;
pronounced vascular network on the bridge of the nose;
hand tremors;
premature extinction of the sucking and swallowing reflex;
profuse and frequent regurgitation;
swelling and protrusion of the fontanelles.

Neurological disorders manifest themselves in the development of strabismus, nystagmus of the eyeballs, deterioration in clarity of vision, hearing, headaches, weakness of the muscles of the limbs in combination with hypertonicity.

In adults and children over 2 years of age, the development of dropsy is signaled by the appearance of morning headaches, vomiting, severe swelling of the optic discs, paresis and other disturbances in coordination of movements.

Hydrocephalus is diagnosed using modern neuroimaging methods. Typically, enlargement of the cerebral ventricles in the fetus is noticed during a screening ultrasound and then confirmed after birth by neurosonography.

In adults, the diagnosis is made during an examination of brain structures using MRI or CT, and in this case, the X-ray examination method will be more informative, since it allows, if necessary, to identify the place of bleeding in the cavity of the ventricles, due to damage or rupture of the blood vessels of the ventricular wall.

Treatment tactics for dropsy of the brain depend on the severity. For small to moderate accumulations of cerebrospinal fluid, specialists carry out drug therapy aimed at reducing the amount of fluid in the brain by taking diuretics.

The work of the nerve centers is also stimulated using physiotherapeutic procedures. Severe pathology requires immediate surgical intervention, which is aimed at reducing intracranial pressure and draining excess fluid from brain structures

Ventriculomegaly

Ventriculomegaly or pathological expansion of the lateral ventricles of the brain is a congenital disease, the true causes of which are still unknown. However, it is believed that the risk of having a child with this disorder increases in women over 35 years of age.

The impetus for the development of pathology can be intrauterine infection of the fetus, trauma to the abdomen of a pregnant woman and uterine bleeding, due to which the child ceases to receive the required amount of nutrients. Often, pathological enlargement of the ventricles of the brain in the fetus is a concomitant disease of other defects of the child’s central nervous system.

Clinically, the expansion (dilatation) of the lateral ventricles manifests itself in the development of neurological abnormalities, since the increased volume of cerebrospinal fluid constrains and puts pressure on the internal structures of the brain. The patient may also experience psycho-emotional disorders, schizophrenia and bipolar disorder.

Ventriculomegaly can be unilateral or bilateral, while a symmetrical and slight increase in the lateral cisterns can be a normal variant and be a feature of the structure of the child’s brain. For newborns, this diagnosis is made only when the dimensions of the diagonal sections of the ventricles at the level of the foramen of Monroe exceed 0.5 cm from the accepted norms.

Pronounced asymmetry of the ventricles requires close attention from specialists - after all, an enlarged cistern on one side upsets the balance of cerebrospinal fluid production. Typically, a child with ventriculomegaly lags behind in development: he begins to speak and walk later, has poor fine motor skills, and also experiences constant headaches. The volume of the skull also grows, and the difference between it and the chest can be more than 3 cm.

Treatment tactics for a child with ventriculomegaly depend on the severity of the disease. Thus, with a mild deviation, the child remains under the supervision of the attending physician; a moderate degree of pathology requires drug treatment and physiotherapeutic procedures aimed at compensating and correcting the neurological manifestations of the disease.

To normalize brain function, the child is prescribed nootropic drugs that improve brain activity, diuretics that reduce intracranial pressure, antihypoxants, potassium-sparing drugs and vitamin complexes.

In case of severe ventriculomegaly, the child requires surgical treatment, which consists of inserting a drainage tube into the ventricles of the brain.

Other causes of pathology of the ventricles of the brain

Dilatation of the cavities of the ventricular system can be caused by damage to brain structures by tumor-like neoplasms or inflammation of its individual parts.

For example, adequate outflow of cerebrospinal fluid may be impaired due to inflammation of part of the soft membrane due to brain damage from meningococcal infection. The basis for damage to the central nervous system by this disease is first the poisoning of the brain vessels with toxins that are released by the infectious agent.

Against this background, tissue edema develops, while bacteria penetrate into all structures of the brain, causing its purulent inflammation. As a result, the membranes of the medulla swell, the convolutions become flattened, and blood clots form inside the vessels, which block the flow of blood, causing multiple cerebral bleeding.

And although this disease is fatal, timely treatment can stop the process of destruction of white matter by infectious agents. Unfortunately, even after a person has completely recovered, there is a risk of developing cerebral hydrocele and, accordingly, enlargement of the cavities of the ventricles of the brain.

One of the complications of meningococcal infection is the development of ependymatitis, or inflammation of the inner lining of the ventricles. It can occur at any stage of the infectious-inflammatory process, regardless of the stage of treatment.

In this case, the clinical course of the disease is no different from the manifestations of meningoencephalitis: the patient experiences drowsiness, prostration, stoppage, or falls into a coma. He also has muscle hypertonicity, tremors of the limbs, convulsions, and vomiting.

In young children, the accumulation of cerebrospinal fluid causes increased intracranial pressure and secondary hydrocephalus of the brain. To make an accurate diagnosis and identify the pathogen, specialists take a puncture of the contents of the ventricles, and in children this procedure is carried out through the fontanelle, and in adults they perform craniotomy

The cerebrospinal fluid puncture specimen for ependymitis is yellow, it contains a large number of pathogenic bacteria, proteins and polynuclear cells. If in the future the disease cannot be treated, then due to the accumulation of a large amount of fluid, all structures and autonomic centers of the brain are subject to compression, which can lead to respiratory paralysis and death of the patient.

The appearance of tumors in the structures of the brain can also cause disruption of the secretion of cerebrospinal fluid and abnormalities in the functioning of the ventricles of the brain. Thus, on the inside of the cisterns and along the outflow pathways of cerebrospinal fluid, ependymoma may appear - a malignant tumor of the central nervous system, which is formed from atypical cells of the ependymal layer. The situation is complicated by the fact that this type of neoplasm can metastasize to other parts of the brain through the cerebrospinal fluid circulation channels.

The clinical picture of the disease depends on where the tumor is located. So, if it is in the lateral tanks, then this manifests itself in increased intracranial pressure, apathy, excessive drowsiness, etc.

As the situation worsens, the patient becomes disoriented, memory impairment, mental disorders, and hallucinations occur. If the tumor is located close to the interventricular foramen or covers it, then the patient may develop unilateral hydrocele of the brain, since the affected ventricle ceases to participate in the circulation of cerebrospinal fluid.

When the fourth ventricle is affected by ependymoma, the patient experiences pronounced neurological abnormalities, since the resulting tumor puts pressure on the cranial nuclei located in its bottom. Visually, this manifests itself in eye nystagmus, paralysis of the facial muscles and impaired swallowing. The patient also experiences headache, vomiting, tonic convulsions or decerebrate rigidity.

In older people, disruption of the ventricular system can be caused by atherosclerotic changes, since as a result of the formation of cholesterol plaques and thinning of the vessel walls, there is a risk of developing cerebral bleeding, including in the ventricular cavity.

In this case, a burst vessel provokes the penetration of blood into the cerebrospinal fluid, which will cause a violation of its chemical composition. Excessive intraventricular hemorrhage can provoke the development of cerebral edema in the sick person with all the ensuing consequences: increasing headache, nausea, vomiting, decreased visual acuity and the appearance of a veil before the eyes.

In the absence of medical care, the patient's condition quickly deteriorates, convulsions appear, and he falls into a coma.

Features of the third ventricle

The 3rd ventricle of the brain is the connecting link between the lateral cisterns and the lower part of the human ventricular system. The cytological composition of its walls is no different from the structure of similar brain structures.

However, its functioning is of particular concern to doctors, since the walls of this cavity contain a large number of autonomic nerve nodes, the functioning of which determines the functioning of all internal systems of the human body, be it breathing or blood circulation. They also maintain the state of the body’s internal environment and participate in shaping the body’s response to external stimuli.

If a neurologist suspects the development of a pathology of the third ventricle, he will refer the patient for a detailed examination of the brain. In children, this process will take place as part of a neurosonological study, and in adults, with the help of more accurate neuroimaging methods - MRI or CT scan of the brain.

Normally, the width of the third ventricle at the level of the aqueduct of Sylvius in an adult should not exceed 4-6 mm, and in a newborn – 3-5 mm. If the subject exceeds this value, then experts note an increase or expansion of the ventricular cavity.

Depending on the severity of the pathology, the patient is prescribed treatment, which may consist of medicinal attenuation of the neurological manifestations of the pathology or the use of surgical treatment methods - shunting the cavity in order to restore the outflow of cerebrospinal fluid.

Video: GM liquor system

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EDUCATION,PATHWAYS OF CIRCULATION AND OUTFLOW OF cerebrospinal fluid

The main route for the formation of cerebrospinal fluid is its production by the choroid plexuses using the active transport mechanism. The vascularization of the choroid plexuses of the lateral ventricles involves the branches of the anterior villous and lateral posterior villous arteries, the third ventricle - the medial posterior villous arteries, the fourth ventricle - the anterior and posterior inferior cerebellar arteries. At present, there is no doubt that, in addition to the vascular system, other brain structures also take part in the production of cerebrospinal fluid: neurons, glia. The formation of the composition of the CSF occurs with the active participation of the structures of the blood-cerebrospinal fluid barrier (CLB). A person produces about 500 ml of CSF per day, that is, the turnover rate is 0.36 ml per minute. The amount of cerebrospinal fluid production is related to its resorption, pressure in the cerebrospinal fluid system and other factors. It undergoes significant changes in conditions of pathology of the nervous system.

The amount of cerebrospinal fluid in an adult is from 130 to 150 ml; of which in the lateral ventricles - 20-30 ml, in the III and IV - 5 ml, cranial subarachnoid space - 30 ml, spinal - 75-90 ml.

The paths of circulation of the cerebrospinal fluid are determined by the location of the main production of fluid and the anatomy of the cerebrospinal fluid tract. As the lateral ventricles form in the choroid plexuses, the cerebrospinal fluid enters the third ventricle through the paired interventricular foramina (Monroe), mixing with the cerebrospinal fluid. produced by the choroid plexus of the latter, flows further through the cerebral aqueduct into the fourth ventricle, where it mixes with the cerebrospinal fluid produced by the choroid plexuses of this ventricle. Diffusion of fluid from the brain substance through the ependyma, which is the morphological substrate of the cerebrospinal fluid-brain barrier (CLB), is also possible into the ventricular system. There is also a reverse flow of fluid through the ependyma and intercellular spaces to the surface of the brain.

Through the paired lateral apertures of the fourth ventricle, the cerebrospinal fluid leaves the ventricular system and enters the subarachnoid space of the brain, where it sequentially passes through systems of cisterns that communicate with each other depending on their location, liquor-carrying canals and subarachnoid cells. Some of the cerebrospinal fluid enters the spinal subarachnoid space. The caudal direction of movement of the cerebrospinal fluid to the openings of the fourth ventricle is created, obviously, due to the speed of its production and the formation of maximum pressure in the lateral ventricles.

The forward movement of cerebrospinal fluid in the subarachnoid space of the brain is carried out through the cerebrospinal fluid channels. Research by M.A. Baron and N.A. Mayorova showed that the subarachnoid space of the brain is a system of liquor-carrying channels, which are the main pathways for the circulation of cerebrospinal fluid, and subarachnoid cells (Fig. 5-2). These microcavities communicate freely with each other through holes in the walls of the channels and cells.

Rice. 5-2. Diagram of the structure of the leptomeninges of the cerebral hemispheres. 1 - liquor-carrying channels; 2 - cerebral arteries; 3 stabilizing structures of cerebral arteries; 4 - subarachpoid cells; 5 - veins; 6 - vascular (soft) membrane; 7 arachnoid membrane; 8 - arachnoid membrane of the excretory canal; 9 - brain (M.A. Baron, N.A. Mayorova, 1982)

The pathways for the outflow of cerebrospinal fluid outside the subarachnoid space have been studied for a long time and carefully. Currently, the prevailing opinion is that the outflow of cerebrospinal fluid from the subarachnoid space of the brain occurs primarily through the arachnoid membrane of the excretory canal region and derivatives of the arachnoid membrane (subdural, intradural and intrasinus arachnoid granulations). Through the circulatory system of the dura mater and the blood capillaries of the choroid (soft) membrane, the cerebrospinal fluid enters the basin of the superior sagittal sinus, from where, through the system of veins (internal jugular - subclavian - brachiocephalic - superior vena cava), the cerebrospinal fluid with venous blood reaches the right atrium.

The outflow of cerebrospinal fluid into the blood can also occur in the area of the intrathecal space of the spinal cord through its arachnoid membrane and the blood capillaries of the dura mater. CSF resorption also partially occurs in the brain parenchyma (mainly in the periventricular region), in the veins of the choroid plexuses and perineural clefts.

The degree of CSF resorption depends on the difference in blood pressure in the sagittal sinus and cerebrospinal fluid in the subarachnoid space. One of the compensatory devices for the outflow of cerebrospinal fluid with increased cerebrospinal fluid pressure is spontaneously appearing holes in the arachnoid membrane above the cerebrospinal fluid channels.

Thus, we can talk about the existence of a single circle of hemocerebrospinal fluid circulation, within which the liquor circulation system operates, combining three main links: 1 - liquor production; 2 - liquor circulation; 3 - liquor resorption.

PATHOGENESISPOST-TRAUMATIC cerebrospinal fluid rhea

Anterior craniobasal and frontobasal injuries involve the paranasal sinuses; with lateral craniobasal and laterobasal - pyramids of the temporal bones and paranasal sinuses of the ear. The nature of the fracture depends on the applied force, its direction, structural features of the skull, and each type of skull deformation corresponds to a characteristic fracture of its base. Shifting bone fragments can damage the meninges.

H.Powiertowski identified three mechanisms of these injuries: entrapment by bone fragments, violation of the integrity of the membranes by free bone fragments, and extensive ruptures and defects without signs of regeneration at the edges of the defect. The meninges prolapse into the bone defect formed as a result of the injury, preventing its healing and, in fact, can lead to the formation of a hernia at the fracture site, consisting of dura mater, arachnoid membrane and medulla.

Due to the heterogeneous structure of the bones forming the base of the skull (there is no separate outer, inner plate and diploic layer between them; the presence of air cavities and numerous openings for the passage of cranial nerves and vessels), the discrepancy between their elasticity and resilience in the parabasal and basal parts of the skull is a tight fit of the dura mater , small ruptures of the arachnoid membrane can occur even with minor head trauma, causing displacement of the intracranial contents in relation to the base. These changes lead to early liquorrhea, which begins within 48 hours after injury in 55% of cases, and in 70% during the first week.

With partial tamponade of an area of damage to the dura mater or tissue interposition, liquorrhea may appear after lysis of a blood clot or damaged brain tissue, as well as as a result of regression of cerebral edema and an increase in liquor pressure during stress, coughing, sneezing, etc. The cause of liquorrhea may be meningitis suffered after an injury , as a result of which the connective tissue scars formed in the third week in the area of the bone defect undergo lysis.

Cases of similar occurrence of liquorrhea have been described 22 years after a head injury and even 35 years later. In such cases, the appearance of liquorrhea is not always associated with a history of TBI.

Early rhinorrhea stops spontaneously within the first week in 85% of patients, and otorrhea in almost all cases.

A persistent course is observed with insufficient juxtaposition of bone tissue (displaced fracture), impaired regeneration at the edges of the dura mater defect in combination with fluctuations in cerebrospinal fluid pressure.

Okhlopkov V.A., Potapov A.A., Kravchuk A.D., Likhterman L.B.