Hydrocephalus - causes, symptoms, types, diagnosis and treatment for children and adults

Hydrocephalus in adults is a pathological condition that is characterized by excessive accumulation of cerebrospinal fluid in the cerebrospinal fluid spaces of the brain. Hydrocephalus can be an independent disease or a consequence of various pathological processes in the brain. Long-term hydrocephalus can lead to disability or death. Effective treatment of hydrocephalus in adults is carried out by neurologists at the Yusupov Hospital.

Causes

Pathology most often develops in newborns, as well as people of retirement age, although people who have not reached it are also at risk of developing this problem. The maximum chance of signs of hydrocephalus appearing is in those who become ill during fetal development. For every 1000 births there are approximately 1-2 such cases.

Several pathological conditions contribute to an increased volume of cerebrospinal fluid (cerebrospinal fluid):

disruption of outflow due to the formation of traffic jams in the outflow tract;
deterioration of fluid absorption by arachnoid granulations;
too much cerebrospinal fluid production.

So far, all the reasons for the development of pathology have not yet been sufficiently studied. Congenital hydrocephalus is often a consequence of a brain defect, due to which there is a deterioration in the circulation of cerebrospinal fluid for the following reasons:

hemorrhage into the cerebral ventricles of the fetus;
incomplete healing of the spinal column;
intracranial hemorrhage;
infectious diseases;
traumatic brain injury;
congenital genetic pathologies;
central nervous system tumors;
arachnoid cysts.

Acquired hydrocephalus can develop in any person due to certain diseases or mechanical injuries:

intracerebral hemorrhage;
formation of venous blood clots in the brain;
stroke;
meningitis;
traumatic brain injury;
development of a tumor in the brain.

Sometimes the vessels through which cerebrospinal fluid flows are narrowed at birth. This pathology can be compensated thanks to the internal reserves of the body. Then hydrocephalus does not appear in the newborn, causing signs of concern only as the child grows older.

In older people, hydrocephalus is called a normotensive disease. This is caused by the situation that the volume of cerebrospinal fluid increases without causing an increase in its pressure. In this condition, intracranial edema occurs, which impairs the functioning of the brain. Conditions in which the natural absorption of cerebrospinal fluid is disrupted increase the risk of developing pathology, although more often the mechanism of development of the disease is unclear. There is a higher risk of infectious meningitis in people who have suffered a traumatic brain injury.

Symptoms of hydrocephalus

Typically, the manifestations of the problem depend on the age of the patient and the type of hydrocephalus. Newborns have noticeable characteristic appearance features:

increased head diameter;
the skin is thin, the veins are visible;
the fontanel protrudes;
eyes are directed downwards.

Clinically, this pathology manifests itself:

frequent vomiting;
lack of appetite;
excessive irritability;
drowsiness;
decrease or increase in muscle tone of the limbs.

The acquired pathology is manifested by frequent headaches, especially severe after a night's sleep. This is due to the fact that when positioned horizontally, cerebrospinal fluid flows more slowly, it accumulates, bursting the brain tissue. The condition improves after standing up, although this improvement gradually disappears as the disease progresses.

Other manifestations include:

neck pain;
drowsiness;
mental disorders;
memory impairment;
the appearance of a “veil” before the eyes;
lack of coordination;
nausea;
walking disorder;
epilepsy;
urinary incontinence, sometimes involuntary bowel movements.

Normal pressure hydrocephalus is a disease of older people. It is characterized by the following symptoms:

walking disorders;
deterioration of intellectual abilities;
urinary incontinence.

The first thing to break is gait. It becomes difficult to start moving. As the disease progresses, instability becomes more pronounced and a person may suddenly fall when changing direction. Walking disorder is accompanied by urinary incontinence: first there is a frequent urge that requires immediate emptying, then control of this function is completely lost.

The disease also affects thought processes:

reaction worsens;
the patient is not able to quickly respond to changing situations;
a failure occurs when trying to process the received information.

How long do people live with this diagnosis?

When cerebral hydrocephalus is diagnosed in an adult, life expectancy depends on several factors:

age of the patient;
duration of disease development;
intensity of symptoms;
selected treatment methods;
reasons for the development of hydrocephalus of the brain.

Most patients manage to return to a full life after treatment, as timely assistance was provided. Some patients decide to visit a doctor when the symptoms of the disease become intense and difficult to bear, in which case the chances of recovery decrease.

Pathogenesis

The disease provokes expansion of the cerebral ventricles for various reasons. The main provocateur is a violation of the outflow of cerebrospinal fluid.

The process of cerebrospinal fluid circulation

The choroid plexuses produce approximately 600–700 ml of cerebrospinal fluid per day. It enters the central canal through special openings, washing the brain and then the spinal cord. Reabsorption occurs through the cerebral hemispheres through the venous sinuses.

Brain damage process

Excessive pressure of the cerebrospinal fluid provokes its leakage into the surrounding substance, which causes the development of edema. The dilated ventricles begin to compress the brain tissue.

The white matter takes the brunt of the attack, causing destruction of the myelin sheaths that transmit nerve impulses to the body.

Up to a certain point, such changes are reversible—after timely surgery, it is possible to almost completely restore neurological functions. Otherwise, atrophy of the brain substance develops, causing spastic paralysis, and the person ceases to control the functioning of the pelvic organs.

In infants, under the influence of such excess pressure, there is a rupture of adhesions inside the subarachnoid space, which opens the way for the outflow of cerebrospinal fluid and self-healing. In advanced situations, brain tissue ruptures. Timely treatment can prevent the development of neurological disorders.

Classification

Based on the openness of the cerebrospinal fluid outflow pathways, hydrocephalus occurs:

closed;
communicating;
substitutive.

According to the characteristics of the deformation of the outflow tract:

internal;
external;
mixed.

By type of cerebrospinal fluid pressure:

hypotensive;
hypertensive;
normotensive.

By etiology:

congenital;
after the inflammatory process;
tumor;
vascular;
idiopathic.

Other types of classification:

with the flow;
by compensation phase;
by activity;
according to the speed of development.

Complications

Excess cerebrospinal fluid dilates the ventricles, compresses the medulla - swelling occurs. A closed cranial cavity provokes the development of irreversible changes in blood vessels - in the absence of the necessary treatment, this condition is life-threatening.

Children who develop hydrocephalus are mentally behind their peers. With complications, mental disorders, mental retardation, personality disorders, and inhibited reactions are likely. Irritability, attacks of euphoria or anger appear. Due to brain damage, speech problems, vision or hearing problems occur.

Adult patients complain of a bursting headache and nausea. Only vomiting sometimes alleviates the condition. The organs of vision experience internal pressure, and there is a feeling as if sand has gotten into the eyes. As pressure increases, drowsiness occurs.

Chronic hydrocephalus provokes an increase in intracranial pressure. The pathology develops slowly, appearing several months after the onset of the disease. Its main symptoms:

cognitive disorders;
walking disorders.

Flow

According to the severity of symptoms, dropsy of the head can be acute, subacute and chronic. In acute hydrocephalus, signs of the disease rapidly increase. This process takes from one day to several days. Subacute “dropsy” of the head develops within a few weeks or a month, and with chronic hydrocephalus, the stage of decompensation occurs within six months.

The prognosis largely depends on how quickly the disease progresses. With compensated hydrocephalus, intracranial pressure remains normal, neurological symptoms do not increase. With a progressive form of the pathology, the patient's condition gradually worsens due to increased intracranial pressure. The disease does not respond well to conservative treatment, and due to constant compression, atrophy of brain tissue develops.

Diagnosis of hydrocephalus

Signs of the disease are often detected while the fetus is still in the womb during ultrasound. Then the disease is diagnosed by a doctor after the baby is born. The main indicator for determining pathology is the large diameter of the skull. In older children, as in adults, the doctor evaluates the patient’s thinking, his gait, the presence of signs of urinary incontinence, and the condition of the ventricles using MRI images.

To verify the presence of congenital hydrocephalus, CT or MRI are used, which allow:

assess the state of the brain;
identify excess cerebrospinal fluid volume;
detect increased cerebrospinal fluid pressure;
see structural changes in brain tissue.

Normal pressure hydrocephalus is more difficult to identify because its symptoms are largely similar to neurodegenerative processes. This variant of pathology is diagnosed according to the following signs:

walking disorder;
mental disorders;
urinary incontinence;
excess volume of cerebrospinal fluid.

With any variant of the disease, it is important to make an accurate diagnosis in a timely manner so as not to be late with surgical intervention that will eliminate the severity of symptoms or reduce their intensity.

To find out how effective the operation will be, some additional measures are necessary:

Lumbar puncture. A small amount of cerebrospinal fluid is removed through a puncture made in the lower back. The cerebrospinal fluid pressure is then measured. The procedure allows you to slightly reduce it in the cerebral ventricles in order to neutralize severe symptoms.
Lumbar drainage. It is necessary when the previous procedure was ineffective. A catheter is installed between the lumbar vertebrae, through which the cerebrospinal fluid comes out for several days. All this time the patient is observed in the hospital. Antibiotics are administered to prevent infection.
Infusion test. This is a stress diagnostic option that helps assess how much the brain is able to absorb cerebrospinal fluid.
ICP measurement. To perform the procedure, a hole is drilled into the skull bone. A sensor in the form of a fiber-optic cable is installed through it. The event is carried out while the patient is in the hospital for at least 24 hours. The sensor detects surges in intracranial pressure, sending values to a recording device.

When an event involves the need to measure ICP, various sensor options are used:

Intraventricular catheter. This is the most accurate way to measure. The device is brought to the lateral cerebral ventricle through a hole drilled in the skull bone. The instrument helps to simultaneously ensure the drainage of excess fluid.
Subdural sensor. The device is attached under the dura mater of the brain. It is used if there is an urgent need to check ICP. The method allows you to quickly identify changes in ICP.
Epidural sensor. The instrument is attached between the dura mater of the brain and the cranial bone, having previously drilled a hole in it. The procedure is less traumatic than others, but has a significant drawback - excess cerebrospinal fluid cannot be drained during the procedure.

When installing sensors, local anesthesia is required. It is also sometimes necessary to additionally inject the patient with sedative medications in order to reduce anxiety and relax the patient as much as possible.

Typically, sensors used to measure ICP are administered to people in intensive care, often in the most critical condition. The necessary indications for such an event are severe trauma to the skull, pathologies of the brain that cause swelling and depression of consciousness up to a coma. In patients who have undergone brain surgery, such a monitoring sensor helps detect increasing swelling.

Drainage of cerebrospinal fluid also helps to reduce high ICP. It is performed by installing a ventricular catheter, intravenous injection of certain medications, and changing the method of ventilation (in a situation where the patient breathes through a tube inserted into the trachea). Normal ICP is 1–20.

Installing sensors is a risky undertaking, as it can cause the following complications if done incorrectly:

bleeding;
irreversible damage in a situation with prohibitive ICP values;
“herniation” of the brain;
damage to brain tissue during catheter insertion;
infectious complications;
inability to accurately determine the location of the ventricle in order to place a catheter to it;
other risks present during general anesthesia of the patient.

Diagnosis of dropsy of the brain

Clinical manifestations are so specific that they allow a neurology specialist to suspect hydrocephalus already during the initial examination of the patient. Despite this, the diagnosis of pathology always involves differentiating hydrocephalic syndrome from other possible diseases that have similar symptoms.

To differentiate, as well as establish the localization, degree and form of hydrocephalus, the etiological factor of its development, according to the doctor’s decision, the leading visual diagnostic tools are prescribed in a certain combination:

magnetic resonance imaging (the most informative);
conventional or multislice CT;
echoencephalography (shows the level of ICP);
neurosonography (done on infants through an open large fontanel to determine ICP);
radiography (more of a backup method, sometimes recommended for assessing the condition of the skull bones).

If cerebral vascular pathology is suspected, the patient is examined using MR angiography. Dropsy of infectious origin additionally involves performing a PCR analysis to identify the type of infection. All patients are prescribed ophthalmological examinations, including examination of the fundus with an ophthalmoscope, eye perimetry, and visometry.

Treatment of hydrocephalus

The option of surgical intervention for hydrocephalus is quite effective. Two types of operations are used: neuroendoscopy or liquor shunting. They are performed by a neurosurgeon, a specialist who can correct problems in the brain or spinal cord, as well as the peripheral nerve ending system.

Bypass surgery

In this type of surgery, a thin tube is inserted into the brain ventricle. Excess cerebrospinal fluid flows through it to another anatomical zone of the body. If the second end of the drainage system is placed in the peritoneum, the shunt is called ventriculoperitoneal. Then the excess cerebrospinal fluid is absorbed by the abdominal cavity and then enters the blood.

When the draining end is directed into the cardiac chamber, the shunt is called ventriculoatrial. This option is practiced during surgery for children, because their increase in height does not affect the functioning of the organ as much, so the drainage does not have to be changed as often as the ventriculoperitoneal system.

Occasionally, lumboperitoneal shunts are also used. With the help of such drainage, cerebrospinal fluid is drained from the lumbar region into the peritoneal cavity.

Any drainage system contains a valve that is set to a certain capacity. It is selected for a specific patient, taking into account the patient’s cerebrospinal fluid pressure. The doctor performing the surgery determines these values in advance by installing a suitable valve, which then looks like a “bump” protruding under the skin on the head.

Currently, neurosurgeons have two types of valves for drainage systems:

With predefined characteristics that define a specific throughput.
Adjustable magnetic fixtures. When choosing them, the doctor remotely, using special equipment, without performing additional incisions, changes the pressure in the device to achieve an optimal result. Thanks to this, it is possible to neutralize adverse side effects in the form of insufficient or excessive cerebrospinal fluid pressure.

Bypass surgery is performed under general anesthesia. The procedure lasts 1–2 hours and after it the patient is kept in the hospital for several days. If the outflow through the shunt is disrupted or the patient becomes infected, a repeat procedure is sometimes performed.

Neuroendoscopy

This operation is an excellent alternative to bypass surgery. Without taking steps to install drainage, the neurosurgeon forms a hole directly in the wall of the cerebral ventricle, after which he creates a bypass path from the vessel through which cerebrospinal fluid flows freely to the surface. There it is absorbed by the brain tissue without obstacles.

This procedure is not universal - it cannot be done on all patients, although this method is often used if the natural cerebrospinal fluid pathways are blocked. In this case, the cerebrospinal fluid flows through the created hole, successfully bypassing all blocked vessels.

The endoscopic procedure is done under general anesthesia. First, the neurosurgeon makes a burr hole with a diameter of 1 cm on the skull. Then, using an endoscope, he examines the inside of the cerebral ventricles. Through the internal channel of the instrument, surgical instruments are inserted, which are used to perform an operation inside the brain. When the endoscope reaches the third ventricle, the doctor creates a hole in its lower wall through which the cerebrospinal fluid penetrates into the subarachnoid cavity. After removing the device, first the aponeurosis is sutured, and then the skin on the skull. The duration of the operation is approximately an hour.

The risk of infection with such an intervention is significantly lower than with cerebrospinal fluid bypass. Neuroendoscopy does not have significant advantages over drainage surgery over long periods of patient observation. After such an intervention, hydrocephalus can also develop again after a few years.

Actions for normal pressure hydrocephalus

When normal pressure hydrocephalus (a common occurrence in older people) is diagnosed, the patient's condition can be improved by performing a cerebrospinal fluid shunt. Although surgery is not effective for every patient. Due to the considerable risks that accompany all operations, certain tests are required to assess how much the potential benefit outweighs the risk of negative consequences.

Almost 80% of patients diagnosed with normal pressure hydrocephalus experienced significant improvement after preliminary testing, so ventriculoperitoneal shunting was recommended for them. Significant clinical postoperative improvement occurs after a few weeks, sometimes even months. Only a timely correct diagnosis guarantees successful recovery even with many years of development of hydrocephalus.

Liquor shunt interventions

CSF shunting is the installation of elastic silicone implant systems to remove cerebrospinal fluid outside the central nervous system. The systems are equipped with catheters in the form of flexible hollow tubes, as well as valves with an anti-siphon (reverse) mechanism and with fixed or adjustable opening pressure.

The operation can be performed in various ways. But surgeons consider ventriculoperitoneal (the most commonly used method) or ventriculoatrial shunting to be the most successful in terms of safety. Interventions are performed under endotracheal anesthesia, manipulations are controlled by intraoperative fluoroscopy, CT, and ECG.

Ventriculo-peritoneal shunt. The principle of the procedure is based on the implantation of silicone catheters, through which an excess of CBF goes into the intra-abdominal cavity, where it is resorbed between the intestinal loops.

A ventricular catheter is introduced through the created access, its end is placed in the lateral ventricle of the brain.
The valve element is implanted in the area of the auricle (at the back or slightly above). The ventricular (ventricular) and distal catheter (DC) are fixed to it.
Next, the neurosurgeon places a distal catheter into the abdominal cavity through a specially formed subcutaneous channel.
Upon reaching the desired abdominal area, the specialist makes a small incision (no more than 10 mm) and inserts the end of the DC into the abdominal cavity.
The procedure ends with thorough disinfection of the surgical field, followed by closing the wound areas with antiseptic dressings (sutures are applied if necessary).

Ventriculoatrial shunting. The essence of this operation is to divert cerebrospinal fluid through installed shunts from the ventricle of the brain into the right atrium.

Dissection of tissue in the neck along the anterior sternocleidomastoid muscle is performed to open the common facial or internal jugular vein.
The atrial catheter is removed into one of the indicated veins, fixing it with specially designed ligatures.
The shunt is directed through the catheterized vein to the right atrium. The end of the atrial shunt is generally located in the superior vena cava.
For the installation area of the distal end of the vascular catheter, yes, the superior vena cava is often preferred. Here the blood flow is turbulent, and this reduces the likelihood of thrombosis of the drainage system by blood clots.
The cranial part of the intervention, when the ventricular element of the system is implanted, a valve and two catheters are connected to it, is identical to VP shunting.

For adults, shunts are permanently implanted. In childhood, they are periodically replaced with elongated models. We emphasize that patients after surgery with shunt implantation are shunt-dependent people.

Prognosis and prevention

It is quite difficult to predict anything in those who suffer from hydrocephalus, although there is a certain connection between the outcome of the disease and the reasons that caused it. Several factors influence the likelihood of pathology:

presence of concomitant diseases;
the period between the appearance of the first signs and the establishment of an accurate diagnosis;
adequacy of the treatment.

Until now, experts have not been able to figure out by what amount it is necessary to reduce ICP during surgery in order to minimize complications or prevent brain damage. Patients, together with their relatives, must understand that pathology harms both mental and physical development. Although after rehabilitation treatment, most children can be brought to a state where they are able to study educational programs and have a minimum of restrictions regarding the quality of life.

The treatment process, which involves doctors of various specialties, and then effective rehabilitation measures coupled with classes conducted by teachers, are extremely important for achieving a positive result. However, you must always remember that the lack of treatment contributes to the progression of hydrocephalus, which is why the disease can be fatal. Only early diagnosis and then adequate treatment guarantee the child’s recovery.

Signs of hydrocephalus, where the cerebrospinal fluid has normal pressure, often progress with age if not properly treated. But sometimes patients suddenly experience unexpected improvements. The effectiveness of organizing liquor shunting measures is not always guaranteed: it depends on the severity of the pathology, the age of the patient, and the reasons that provoked the development of the disease.

Sometimes, thanks to a complex of timely treatment, it is possible to achieve complete restoration of lost neurological functions. Therefore, the prognosis of how the pathology will proceed further when a shunt system is installed depends only on the patient’s body’s perception of such intervention. The main complications are blockage, infection or disconnection of the system:

The first complication develops due to the entry of body particles into the drains. Blockage can also be caused by a malfunction of the valve device. Typically, liquor shunt systems operate for 5–10 years. If a blockage occurs, a complete replacement of the drainage is required.
Infection develops when bacteria enter the tubes. Such a complication is likely during surgery, at the time of installation of the system, and also due to the migration of pathogenic microorganisms. Liqueur bypass systems are made of silicone. This material itself is foreign to the body, which makes it impossible to cure the infection with antibiotics. If such a complication is detected, immediate removal of the shunt system and a further course of therapy are required. Only after complete recovery is a new system implanted. To reduce the risk, it is recommended to use silver-impregnated equipment.
Disconnection can occur when the seal in the tubes is broken. The cause is the movement of the shunt inside the patient's body, which often occurs in children due to natural growth. When system disconnection occurs, it is necessary to organize immediate surgical intervention, which involves checking the functionality of the shunt system and correcting areas that have lost their tightness.

Complications such as cerebral hemorrhage occur much less frequently (they are likely at the time of catheter installation), as well as disconnection of the catheter, after which it moves into the cavity of the cerebral ventricle. When such an event occurs, it is not always possible to remove the foreign object, so the associated infection becomes the cause of epilepsy or convulsive seizures.

Most patients who have undergone surgery for such an unpleasant reason lead an almost comfortable lifestyle. Almost 10% of them get rid of foreign implanted systems over time.

Nowadays, prevention of pathologies that can provoke hydrocephalus is carried out everywhere. To prevent meningococcal infection, which leads to infectious meningitis, active vaccination is used, and antibacterial agents are prescribed to those who have been in contact with an infected person to minimize the risk of infection. To prevent the possibility of rupture of identified arterial aneurysms in the brain, which cause subarachnoid hemorrhage, surgical interventions are organized to help exclude the aneurysm from the general blood flow.