Arachnoid cyst
Last reviewed: 23.04.2024
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Arachnoid cyst is a fluid-filled cavity, the walls of which are lined with cells of the arachnoid shell. Such formations are located between the surface of the brain and the arachnoid shell.
Arachnoid cyst can be congenital or acquired. The latter arise as a result of severe diseases, such as inflammation of the membranes of the brain and spinal cord, Marfan's disease, congenital complete or partial absence of the corpus callosum, and also after surgical interventions. The walls of such cysts cover spider webs.
According to statistics, such tumors are more often formed in males. Usually they are located within the liquor spaces containing numerous arachnoid shells and increase them in volume. The most common arachnoid cysts are located in the part of the inner base of the skull formed by the wedge-shaped and temporal bones, outside of the temporal lobes.
The arachnoid cyst of the brain is a hollow, rounded formation filled with a liquid whose walls are made up of cobweb cells. Such formation is formed between the cerebral membranes and at the pressure of the CSF contained inside the tumor, symptoms such as dizziness, headache, ringing in the ears, etc. Can cause on any part of the brain. The larger the size of the cyst, the more pronounced the signs of the disease, up to development of such serious disorders as deterioration of hearing and vision, speech and memory functions, seizures, etc.
To provoke growth of a tumor inflammatory processes, brain traumas, and also increase in quantity of a liquid in a cyst can. Diagnosis of the disease and determine the size and location of the tumor allows the method of magnetic resonance as well as computed tomography.
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Causes
Arachnoid cyst can be a congenital pathology or develop as a result of injuries and severe diseases. Causes of arachnoid cyst of secondary origin may be associated with inflammation of the spinal cord and brain, agenesis of the plexus of brain nerve fibers that unite the right and left hemispheres (corpus callosum), hereditary autosomal dominant connective tissue disease (Marfan's disease), and surgical interventions.
The main reasons for the growth of such formations may consist in increasing the pressure of the intracavitary fluid, in the development of inflammation of the brain envelopes, and may also be associated with traumatization, for example, with concussion of the brain.
Symptoms
Symptoms of the arachnoid cyst, as well as the degree of their severity, depend on the location and size of the lesion. As a rule, the symptomatology of the disease manifests itself in the age of up to twenty years, and this kind of tumors can exist without manifesting any symptoms.
The main symptoms of the formation of the arachnoid cyst include headaches, a feeling of nausea, vomiting, impaired coordination of movements, partial paralysis of the body, hallucinations, seizures, mental disorders.
Retrocerebellar cyst
There are several types of cysts that can form in the brain. The main ones are the retrocerebellar, arachnoid cyst. When this type of tumor is formed, the fluid accumulates between the layers of the meninges, while in the development of the retrocerebellar cyst it forms inside the brain.
The arachnoid cyst is located on the surface of the brain, retrocerebellar cyst is located in its space. As a rule, the arachnoid cyst arises as a result of inflammatory processes in the meninges, hemorrhages and brain injuries.
Retrocerebellar cyst is located on the already affected area of the brain. To prevent damage to the entire brain, it is extremely important to identify in time the causes that led to the withering away of its site. Basically, this is a lack of cerebral blood supply, inflammatory processes of the brain, as well as intracranial surgery.
Arachnoid cyst of temporal lobe
The arachnoid cyst of the temporal lobe on the left may be asymptomatic or manifest as such signs as:
- headache
- feeling of pulsation and squeezing in the head
- the occurrence of noise in the left ear, not accompanied by hearing impairments
- hearing impairment
- nausea
- vomiting reactions
- occurrence of seizures
- problems with coordination of movements
- partial paralysis
- numbness of different parts of the body
- hallucinations
- mental disorders
- fainting
Arachnoid cyst of the spine
The arachnoid cyst of the spine is a globular cavity with liquid contents, the walls of which lining the cobweb cells. The arachnoid cyst of the spine refers to benign formations that can lead to the development of pain in the lower back.
At the stage of formation, the disease is asymptomatic. The first signs appear, as a rule, at the age of up to twenty years. Since the arachnoid cysts of the spine differ in size and location, it is often necessary to carry out differential diagnosis in order to fully verify the presence of a cyst. In some cases, tumors resemble the symptoms of a herniated intervertebral disc.
Arachnoid cyst of posterior cranial fossa
The arachnoid cyst of the posterior cranial fossa is similar to the cyst produced by the anomaly of the cerebellum development and the liquor spaces around it. The cerebellum occupies almost the entire posterior cranial fossa. When performing differential diagnosis, the structure of the cerebellum is analyzed and, in the case of a defect in its worm, the arachnoid cyst of the posterior cranial fossa is excluded.
[18], [19], [20], [21], [22], [23]
An arachnoid cyst and cyst of a cerebellum
The arachnoid cyst and the cerebellar cyst differ in structure and place of localization.
The cerebellum cyst refers to tumors that form inside the brain and is a fluid accumulation at the site of the affected area of the brain. To prevent further brain damage, the causes of this pathology must be identified. Most often intracerebral cysts occur as a result of violations of the blood circulation of the brain, strokes, injuries, inflammatory processes, as well as surgical interventions inside the skull.
Unlike an intracerebral cystic tumor, the arachnoid cyst is always localized on the surface of the brain, in the region of its membranes.
Perineural arachnoid cyst
The perineural arachnoid cyst is localized in the spinal canal and is characterized by fluid accumulation in the spine cord root region.
Most often the perineural cyst is located in the lumbar region and the sacrum. The main reasons for the appearance of such formations include inflammatory processes, as well as trauma. There are also cases of spontaneous appearance of perineural cysts.
Cystic education up to 1.5 cm in size can not be accompanied by any symptoms and its detection is possible only during preventive examination. With an increase in tumor volumes, it exerts pressure on the root of the spinal cord around which it is localized. Symptoms such as pain in the lumbar region and sacrum, lower extremities, a feeling of crawling, and irregularities in the operation of the pelvic organs and the urinary system appear.
Differential diagnostics with suspicion of perineural cyst formation can be carried out with such diseases as intestinal colic, appendicitis, inflammation of the uterine appendages, osteochondrosis.
The most accurate diagnosis of the perineural cyst allows such methods of investigation as computer and magnetic resonance imaging. When carrying out an X-ray examination, such tumors are not determined.
Treatment of a small perineural cyst can be conservative (requiring no surgical intervention). The operation is indicated for a severe course of the disease, which has a negative effect on the functioning of any organs. However, it should be noted that during surgery, there are risks such as trauma to the spinal cord, the formation of adhesions, the development of postoperative meningitis and the re-emergence of the tumor. The expediency of the operation is determined by the attending physician on the basis of a general examination and accompanying symptoms.
Arachnoid cyst of the Sylvian fissure
The arachnoid cyst of the sylvium crack is classified according to a number of characteristic features and can be of several types:
- small sizes, as a rule, bilateral, communicating with the subarachnoid space
- rectangular shape, communicating with the subarachnoid space in part
- Damage to the entire Sylvian gap, not connected with the subarachnoid space
Symptoms of the cyst of the sylvium gap include increased intracranial pressure, bulging of the cranial bones, epileptic seizures, hydrocephalus due to compression of the ventricles of the brain, visual disturbances.
[27], [28], [29], [30], [31], [32], [33]
Arachnoid cyst
The arachnoid cyst is formed in the shell of the brain and is a round cavity filled with liquid contents (cerebrospinal fluid). According to statistics, such neoplasms are more often found in males. Diagnosis of the disease, usually in adulthood, because in the earlier period, the symptomatology is not sufficiently expressed.
The arachnoidal cyst can be congenital or acquired. The congenital form of this nosology is formed as a result of violations during embryogeny (embryonic development). The presumed cause of this formation is the injury of the fetus during the development of the meninges. Such formation can be detected during an ultrasound examination.
Acquired arachnoid cyst is the result of an inflammatory process in the membranes of the brain, trauma or hemorrhage to the brain.
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Arachnoid cyst parietal region
The arachnoid cyst of the parietal region is a benign volumetric neoplasm with a cavity filled with a fluid like cerebrospinal fluid. This type of tumor can be a consequence of the development of inflammatory processes of the brain, as well as injuries. The consequence of this neoplasm in untimely treatment can be serious impairment of mental functions, memory, speech, as well as hearing and sight.
Depending on the indications, the arachnoid cyst of the parietal region can be removed by the endoscopic method or surgically. As a rule, indications for the removal of such education are the rapid growth and increase in the size of the tumor, the development of severe symptoms, the pressure of the tumor on the brain areas.
Diagnosis of the arachnoid cyst of the parietal region is performed using computer or MR-tomography techniques.
Convexual arachnoid cyst
A convective arachnoid cyst is formed on the surface of the cerebral hemispheres and is a hollow, rounded formation with liquid contents, the walls of which consist of cells of the arachnoid shell.
At small sizes of a cyst and absence of the expressed symptomatology treatment in most cases do not spend. However, with an increase in the amount of intracavitary fluid, the tumor can exert pressure on the brain regions, thus causing a number of characteristic symptoms, such as: headaches and dizziness, vomiting and nausea, hallucinations, noise or ringing in the ears, disorders of various body functions,
In such cases, the tumor can be removed surgically or endoscopically, as well as by shunting.
Arachnoid cyst of the Turkish saddle
The Turkish saddle is located in the projection of the wedge-shaped cranial bone and represents a small depression, resembling a saddle in appearance.
The arachnoid cyst of the Turkish saddle is a tumor-like formation having a cavity consisting of cells of the arachnoid shell and liquid contents. To diagnose such pathology it is possible by means of methods of computer or MR-tomography. Treatment is appointed based on the size and progression of the neoplasm and can be carried out using endoscopic or surgical methods, as well as by shunting.
Arachnoid cyst of lumbar region
The arachnoid cyst of the lumbar region is formed in the lumen of the spinal canal and can exert pressure on the nerve endings of the spinal cord, thus provoking the development of the pain syndrome. In most cases, such formations are detected accidentally during the examination of the lumbar spine.
Lead to the development of the arachnoid cyst of the lumbar spine may be osteochondrosis, inflammatory processes of the lumbar spine, as a result of which the rootlet of the nerve endings of the spinal cord and its filling with a liquor substance are expanded.
To provoke this kind of tumor can also traumatize this area. In some cases, the occurrence of such formations does not have well-defined causes.
Arachnoid cyst of sacral region
The arachnoid cyst of the sacrum is filled with cerebrospinal fluid, and its walls are lined with cells of the arachnoid membrane.
This kind of tumor can be a congenital education. With a small tumor size, the symptomatology is usually not expressed. With an increase in the size of the tumor, it can put pressure on the nerve endings that come out of the spinal cord and cause moderate or severe pain.
In this case, pain can be felt both in the process of motor activity and at rest, for example, while in a sitting position. Pain can irradiate into the buttocks, lumbar region, be felt in the abdomen and be accompanied by disorders of stool and urination. In the lower extremities, there may be a feeling of crawling, a weakening of the muscles.
Congenital arachnoid cyst
A congenital arachnoid cyst (true, or primary) occurs during embryonic development and can be triggered by trauma or some developmental abnormality. Presumably, the emergence of primary arachnoid cysts is associated with a disruption in the formation of the arachnoid or sub-abdominal space in embryogenesis. The exact causes of congenital arachnoid cysts have not been fully investigated. A congenital arachnoid cyst can be combined with a more severe CNS pathology. Its detection can be accidental in the diagnosis of other diseases, since such cysts can exist asymptomatically. However, with the progression of the tumor, the symptoms become quite pronounced, headaches, noise or ringing in the ears, convulsions, hearing and visual impairment, as well as other serious symptoms that require immediate medical attention.
[53], [54], [55], [56], [57], [58], [59], [60]
Arachnoid cyst in children
The arachnoid cyst in children can be formed due to inflammatory processes, which were transferred during the intrauterine period. Also, the cause of the appearance of such a neoplasm can be trauma in the process of childbirth, violations in the development of the fetus during the formation of the embryo, a disease of meningitis.
The tumor requires constant monitoring of the doctor. With rapid progression and severe symptoms of the disease, a decision can be made to remove the tumor. The method of ultrasound can be used to diagnose an arachnoid cyst.
Arachnoid cyst in a newborn
The arachnoid cyst in a newborn can be the result of transferred meningitis or other inflammatory processes, as well as brain trauma. Causes may also be associated with congenital pathology.
To diagnose an arachnoid cyst in a newborn, the ultrasound method is used. Since this kind of tumor does not dissolve on its own, it requires constant monitoring of the doctor. Decision-making on the appropriateness of surgical intervention depends on such factors as the progression of the tumor and the severity of the symptoms of the disease.
What is dangerous arachnoid cyst?
When forming an arachnoid cyst, the patient should be under the supervision of a doctor and monitor the progress of the disease. Undoubtedly, in patients with this diagnosis, the question arises: "What is dangerous arachnoid cyst?".
First of all, it should be noted that in the absence of timely treatment and the rapid progression of formation within the tumor, fluid that pressures the brain regions can continue to accumulate. As a result, the symptoms of the disease increase, various disorders of the visual, auditory organs, as well as memory and speech functions develop.
In the event of rupture of the arachnoid cyst, as well as in severe forms of the disease, the lack of proper treatment, the consequences can lead to the death of the patient.
Effects
The consequences of an arachnoid cyst with untimely treatment of the disease can lead to accumulation of fluid inside the neoplasm and increase pressure on the brain areas. As a result, the symptomatology of the disease increases, and various serious disturbances of visual, auditory, speech functions, memory can occur. With the rupture of the arachnoid cyst, as well as with the advanced stage of the disease, the consequences can be irreversible, including death.
Diagnostics
Diagnosis of the arachnoid cyst is performed using methods of magnetic resonance imaging or computed tomography. In rare cases, with damage to the posterior cranial fossa or the formation of median suprasellar cysts, an X-ray examination can be performed after the introduction of a contrast agent into the subarachnoidal cisterns or ventricles of the brain.
Treatment
Treatment of an arachnoid cyst in the absence of symptoms and the progression of the disease, as a rule, is not carried out. The patient should be under the supervision of a doctor with a view to timely detecting an unfavorable course of the disease.
With a rapid increase in the size of the tumor, the appearance of severe symptoms of the disease can be prescribed surgical treatment.
Methods used to remove neoplasms include radical surgical interventions, in which trepanation of the skull and subsequent removal of the tumor is carried out. It should be noted that when using this method of treatment of arachnoid cyst, there is a risk of traumatization.
Removal of the tumor can be carried out by shunting, in which the drainage tube provides an outflow of its contents. When using this method, there is a possibility of infection.
Endoscopic removal is performed by piercing the neoplasm and pumping out the intracavitary fluid. Traumatization using this method is minimal, but for some types of formations it is not used.
Removal of the arachnoid cyst
The removal of the arachnoid cyst can be performed using the following methods:
- Shunting - ensuring the outflow of its contents into a slot-like space between the hard and arachnoid shells of the brain.
- The method of fenestration, in which the tumor is excised by trepanation of the skull.
- Drainage by pumping out the contents with a needle.
Prevention
Prevention of arachnoid cyst can consist of early diagnosis and timely treatment of inflammatory processes of the brain, various infections and craniocerebral trauma.
Forecast
The prognosis of the arachnoid cyst with timely detection of neoplasm and qualified treatment is favorable. The main risks in the formation of this kind of tumor are associated with an increase in its size and an increase in pressure on the brain areas, as well as the possibility of rupture of the tumor. The prognosis of the disease in such cases may include the development of rather serious complications that can lead to disruption of various functions - memory, speech, hearing, vision. With the advanced form of the disease, the arachnoid cyst of the brain can lead to the development of hydrocephalus, brain hernia or death.
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