Clinical manifestations of intracranial tumor. Intracranial tumor Tumor in the cranial fossa - symptoms

For intracranial tumors Both conventional methods of X-ray examination of the skull (craniography) and artificial contrast methods (encephaloventriculography and angiography) are used. Contrasting methods, despite their significant value, have not yet found wide application. This is explained by the fact that they are quite complex and require mandatory joint work of a neurosurgeon and a radiologist and conduct the entire study in an appropriate clinical setting. In addition, they are not always safe and have a certain mortality rate.

In contrast to this craniography is a relatively simple research method that can be carried out in any X-ray room. According to a number of authors, with the help of craniography, in almost 40% of cases it is possible to establish not only the presence of a tumor process in the brain, but also the location and nature of the tumor. Of course, the radiologist must be well acquainted with the topographic and x-ray anatomy of the skull, and also be able to compare the data obtained from x-rays with the entire clinical picture. The research technique itself must be perfect, because a correct judgment about the nature of pathological processes in the cranial cavity largely depends on the quality of radiographs. In the future, we will not touch on contrast methods, but will focus exclusively on craniography data.

Due to the fact that it is correct comparison Since the clinical picture with craniography data is extremely important for the diagnosis of an intracranial tumor and determining its location, we consider it appropriate to dwell on some ophthalmological symptoms of these tumors.

One of the most important symptoms is a stagnant nipple. Congestive nipples are observed in more than 75% of intracranial tumors. However, they only indicate the presence of increased intracranial pressure, but not at all the nature of the process itself and its localization. Vision with congestive nipples can be preserved for a long time, which, by the way, should be taken into account in the differential diagnosis with optic neuritis. In rare cases, patients note a rapidly transient fogging, sometimes quite frequent (up to 50-100 times a day). This forces patients to consult an eye doctor, who detects congestive nipples and is the first to determine the presence of increased intracranial pressure.

For diagnosis intracranial processes A thorough examination of the visual field is important. The study of visual field defects allows in some cases to quite accurately determine the location of the process. Thus, with complete loss of the visual field in one eye (unilateral amazonosis), the process is located in the area between the optic nerve canal and the chiasm, provided, of course, that the process is not in the orbit. If the process involves the optic nerve and half of the chiasm, then there is a complete loss of the visual field in one eye and loss of the temporal half in the other. When the process is localized in the area of ​​the middle part of the chiasm, loss of the outer halves of the visual field of both eyes is noted (bitemporal hemianopsia).

If there are two symmetrical lesions Binasal hemianopsia is observed in the lateral corners of the chiasm. Such loss of the inner halves of the visual field is extremely rare. However, the possibility cannot be excluded that when the pituitary tumor grows sideways, the chiasm may become compressed in the lateral angles, as a result of which binasal hemianopsia develops. When the process is localized behind the chiasma from the optic tract to the visual centers in the occipital lobe cortex, the same name (homonymous) hemianopsia is noted. But even here, by some signs, it is possible to determine where the process is located that caused a conduction interruption in the visual pathway.

We have provided only a diagram here possible changes in the field of view with intracranial processes, but the radiologist's familiarity with even such a simplified diagram may be valuable for understanding the changes detected on radiographs of the skull.

From ophthalmological signs The state of pupillary reactions also matters. For example, a hemianopic reaction of the pupils indicates that the process is localized in the area of ​​the chiasm or optic tract before the departure of the pupillary fibers to the nuclei of the oculomotor nerve. On the contrary, the pupillary response may be preserved when the process is located behind the nuclei of the oculomotor nerve.

Violation of the innervation of the eye muscles It also has a known diagnostic value. However, it must be borne in mind that paralysis can be caused by both a process in the orbit and an intracranial one. In the latter case, with the so-called basal palsies, paralysis of other cranial nerves is often simultaneously observed.

It should also not be overlooked mind, that exophthalmos can be caused not only by a retrobulbar process in, but also by an intracranial tumor. Unilateral exophthalmos can be observed when a tumor grows from the anterior and middle cranial fossa into the orbit. Severe unilateral exophthalmos is often caused by hyperostosis of the wings of the main bone with the development of meningioma in this area. Some authors believe that compression of the cavernous sinus by a nearby tumor may also cause unilateral proptosis. With increased intracranial pressure, bilateral exophthalmos is sometimes observed, especially in childhood, which is probably due to pressing forward of the walls of the orbits.

Bilateral exophthalmos can also occur with thrombosis of the cavernous sinus, but a number of other characteristic signs are also noted, as a result of which differential diagnosis with an intracranial tumor does not present any particular difficulties.

Intracranial tumors develop from brain tissue, its membranes and skull bones. Tumors are divided into primary, originating from brain tissue, and secondary, metastatic.

Of the primary tumors, the most common are gliomas that develop from the medulla. They have infiltrating growth, lack clear boundaries, and can occur in all parts of the brain. Tumors called meningiomas (endotheliomas) arise from the meninges. Tumors have a benign course, slow growth, and sometimes reach significant sizes.

Secondary tumors are in most cases metastases of breast or lung cancer.

An intracranial tumor causes compression of local tissues and also affects the blood supply to the brain, compressing the ventricles of the brain, disrupting the outflow of cerebrospinal fluid from the cavities of the skull.

Clinical picture of intracranial tumor

The clinical picture of an intracranial tumor is determined by local and general symptoms. Common symptoms include headache, nausea, vomiting, dizziness, and nipple congestion.

Headache is often the initial symptom. The pain covers the entire head or is localized at the location of the tumor, sometimes reaching extreme intensity. Vomiting is not associated with food intake, it occurs in the morning, on an empty stomach, when the patient moves from a horizontal to a vertical position. At first, vision is not affected, but then, due to atrophy of the optic nerve, complete blindness can occur.

With tumors of the frontal lobes, one of the first symptoms is mental disturbance in the form of foolishness, euphoria, a tendency to flat jokes and inappropriate jokes. When the tumor is localized on the lower surface of the frontal lobe, the olfactory bulb is compressed and therefore the sense of smell is weakened or lost.

The symptoms are most clearly expressed when the tumor is localized in the anterior central gyrus. Active movements in the lower and upper limbs, neck, facial and other muscles are lost, depending on the location of the tumor. Initially, paresis and then paralysis are observed on the side opposite the tumor. Paralysis can affect the entire half of the body (hemiplegia).

When the tumor affects the temporal lobes, auditory hallucinations are observed. Tumors of the occipital region cause loss of visual fields in both eyes and visual hallucinations. Cerebellar tumors are characterized by loss of the ability to produce appropriate muscle contractions during movement and imbalance when walking.

Diagnosis of intracranial tumor

The diagnosis of an intracranial tumor can be made based on the medical history and a thorough neurological examination of the patient.

For a long time, it was believed that metastases account for about 20% of tumors of the central nervous system (CNS), and their incidence is approximately 2 per 100 thousand of the population.

With the advent of modern examination methods and the increase in life expectancy of cancer patients, it became clear that currently the incidence of metastatic (secondary) tumors of the central nervous system is about 14 per 100 thousand population per year, i.e. exceeds the incidence of primary CNS tumors.

However, so far the number of patients with intracranial metastases in neurosurgical clinics does not exceed 20-25%. This is due to the fact that cancer patients in stage IV of the disease, even if they have appropriate symptoms, are usually not referred to neurosurgeons.

However, even in these cases, intracranial metastases may be the most significant cause of the severity of the condition and, ultimately, the death of the patient, and modern neurosurgical treatment can improve the quality and increase life expectancy.

In adults, the most common metastases (in 40% of cases) are lung cancer (usually small cell), breast cancer (10%), renal cell cancer (7%), gastrointestinal cancer (6%) and melanoma (from 3 up to 15% in different countries). The number of metastases in the central nervous system of all other tumors does not exceed 15%.

In children, metastases of neuroblastoma, rhabdomyosarcoma and Wilms tumor (nephroblastoma) are most often observed.

In 50% of cases, brain metastases are single, in 50% - multiple. They can be located in various anatomical structures of the brain: in the medulla, in the dura or pia mater, in the subarachnoid space and ventricles of the brain and spread along the cerebrospinal fluid tract and perivascular spaces.

Carcinomas and sarcomas more often metastasize to the brain; metastases in leukemia predominantly affect the soft meninges; breast carcinomas tend to metastasize to the dura mater with spread to the brain tissue. Prostate carcinomas most often metastasize to the skull and spine, and less often to the brain and spinal cord.

Most metastases affect the cerebral hemispheres, usually the white matter. Metastases to the brain stem and spinal cord are rare. Lung cancer metastases may be accompanied by suppuration.

Intracerebral metastases are often round in shape and usually delimited from the medulla. In many cases, there is swelling of the tissue around the tumor node. Sometimes swelling can be very pronounced even with small metastases.

Intracerebral metastases often have a low degree of differentiation and do not fully display the morphological characteristics of the primary tumor. This makes diagnosis difficult, especially with metastases from an undetected primary site.

Cytological examination of the cerebrospinal fluid may be advisable only if the tumor has spread through the cerebrospinal fluid spaces; therefore, in other cases, a spinal puncture is usually not performed before surgery.

Clinical picture

The basis for suspicion of metastatic brain damage in a cancer patient may be the appearance of neurological symptoms, although in approximately 30% of cases metastases in the central nervous system may not appear. When symptoms appear, they gradually increase in severity.

Diagnostics

The presence of metastases in the central nervous system is confirmed using magnetic resonance imaging (MRI) with contrasting with a special preparation. Typically, metastases appear as areas of increased signal.

The presence of a single lesion identified by MRI or computed tomography(CT) in patients with advanced cancer is not a clear sign of metastatic brain damage.

If a ring-shaped lesion is detected, it should be differentiated from an abscess (suppuration), hematoma (hemorrhage) in the resorption stage, malignant glioma, granuloma, or radiation necrosis.

In doubtful cases, it is carried out stereotactic biopsy lesion in order to clarify the histological diagnosis.

In 15% of cases, intracranial metastases are the first manifestation of cancer. Therefore, with an unknown primary lesion, taking into account the most likely sources of metastasis in the central nervous system, a detailed examination is necessary to identify the primary tumor.

All patients are recommended to be examined by an oncologist, including radiography and (with negative X-ray results) CT of the chest organs, mammography (in women), radioisotope scanning bones, fecal occult blood test. Sometimes histological examination of a removed tumor in the brain helps to identify the source of metastasis.

Treatment

Surgery is an effective method for many types of metastases and is especially indicated for the treatment of tumors that are not sensitive to radiation.

To decide on indications for surgery, the patient’s general condition, the technical feasibility of removing metastases, and the prospects for combined treatment in the presence of metastatic lesions of other organs and systems are assessed.

Modern technical capabilities make it possible to diagnose and operate metastases at an early stage and small sizes.

The use of modern ultrasound diagnostic methods makes it possible to accurately localize the tumor, determine the direction of access and avoid damage to functionally significant areas of the brain.

Removal of metastatic tumors, especially large ones and located in functionally important areas, is usually carried out according to the same principles as other CNS tumors, i.e. fragmentation.

The likelihood of complete destruction of the tumor after surgery can be increased by irradiating the tumor bed with a laser beam. Experimental work is underway on the use of photodynamic therapy during surgery.

RADIATION THERAPY

For metastatic tumors of the central nervous system, irradiation of the entire brain is necessary in most cases. For this purpose, lateral opposite fields are used.

They should cover the space from the vault to the base of the skull and from the upper edge of the orbit to the mastoid process. If the tumor is located in the lower part of the frontal or temporal lobe, the radiation field should cover the lower edge of the orbit and the external auditory canal. In this case, blocks are installed on the lens and base of the skull.

The usual dose is 20 Gy in 4-5 fractions or 30 Gy in 10-12 fractions.

Considering the long-term side effects (dementia) at a dose of 30 Gy in 10 fractions, it has recently been recommended to carry out irradiation in fractions of 1.8-2 Gy, but the effectiveness of treatment in this case decreases.

When treating single metastases, local irradiation of the lesion is added to a total dose of 50 Gy. In the presence of deeply located and (or) multiple small metastases, radiosurgical treatment is indicated.

Prophylactic irradiation of the brain after removal of small cell lung cancer reduces the number of intracranial metastases, but does not affect survival rates.

CHEMOTHERAPY

The choice of chemotherapy regimen depends on the nature of the primary source of metastasis.

SYMPTOMATIC TREATMENT

The goal of treatment of patients with single or multiple metastases in the first stages is to stabilize acute neurological symptoms caused by increased intracranial pressure or convulsive syndrome. The decongestant effect of steroid drugs (dexamethasone at a dose of at least 8 mg per day) contributes to the reverse development of hypertension and neurological symptoms.

Generalized or partial (partial) seizures are observed in patients with metastases to the central nervous system in 20% of cases, more often when the node is located near the cerebral cortex. Prescription of anticonvulsants (usually barbiturates or carbamazepine, depending on the characteristics of the attacks) leads to a decrease in the severity of symptoms.

Thus, the following treatment can be recommended for patients with metastases to the central nervous system. If a single metastasis is detected in the brain or spinal cord, its removal followed by radiation and (if necessary) chemotherapy is indicated. The presence of metastases to other organs is not an absolute contraindication for surgery. When making a decision, the severity of the patient’s condition and the availability of further treatment are taken into account. An alternative method of therapy can be radiosurgery (a gamma knife or a linear accelerator is more often used).

Pathological anatomy and pathological physiology. Brain tumors are divided into primary, originating from brain tissue, blood vessels or meninges and peripheral cranial nerve fibers adjacent to the brain; and secondary, metastatic.

Of the primary tumors, the most common are gliomas, which are observed in all parts of the brain and begin from the medulla. Gliomas usually exhibit infiltrating growth and therefore lack clear boundaries. Sometimes glioma is soft, grows quickly and is prone to bleeding into the tumor tissue, sometimes it grows more slowly, prone to decay and the formation of cysts. Histologically, gliomas are divided into astrocytomas, consisting of stellate cells and having a relatively benign course, oligodendrocytes, glioblastomas, consisting of polymorphic cells, and rapidly growing medulloblastomas, consisting of small round cells, and other, rarer forms.

The second most common type of brain tumor is meningiomas (endotheliomas) arising from the meninges. Most meningiomas are benign, usually solitary, slow-growing tumors composed of endothelial cells and significant amounts of connective tissue. Often meningiomas reach a significant size and are deeply pressed into the brain, pushing its convolutions apart (Fig. 20). Calcareous salts are sometimes deposited in meningiomas, and then they are called psammomas. Meningiomas may not produce any clinical symptoms for a long time. Next come adenomas originating from the appendage of the brain.

Other rarer tumors include ependymomas starting from the ependyma of the ventricles, papillomas originating from the choroid plexus, neuromas, angiomas, and dermoids.

Secondary brain tumors are metastases from other areas of the body, usually breast cancer or lung cancer. Metastases of tumors to the brain are mostly multiple. Cases of successful removal of single metastases have been described.

Tumors arising from the bones of the skull and growing into the cranial cavity are osteomas of the ethmoid-frontal region and osteosarcomas of the vault. Often occurring metastatic tumors of the skull bones do not produce symptoms of brain compression.

The clinical picture of a brain tumor can also be given by limited accumulations of fluid located between the dura and arachnoid mater and representing the consequences of meningitis - and rachnoid cysts.

Based on their location, they distinguish between extradural (extradural) and intradural (intradura) tumors, which in turn are divided into extracerebral (extracerebral) and intracerebral (intracerebral). Intracerebral tumors are divided into cortical and subcortical.

An intracranial tumor affects the contents of the skull in three ways: locally, by direct pressure on an adjacent area of ​​the brain, on a separate area of ​​the brain, and on the entire brain (compression of blood vessels and disruption of the circulation of cerebrospinal fluid).

Compression of the blood vessels by the tumor is reflected primarily in the compliant veins, which results in swelling of the supplied part of the brain, and this part can be very significant. Compression of the artery causes ischemia. A circulatory disorder is accompanied by impaired function of swollen or anemic areas of the brain, which causes the appearance of additional brain symptoms that make it difficult to recognize.

Disruption of the normal circulation of cerebrospinal fluid has even more important consequences. The tumor, displacing the ventricle, often disrupts the normal flow of cerebrospinal fluid from the lateral ventricles of the brain through the third and fourth ventricles into the foramina of Magendie and Luschka, and from there into the cistern magna and beyond.

Brain tumor may compress the lateral ventricle, close the foramen of Monro and cause partial fluid retention (Fig. 21). A tumor located in the pituitary region or in the region of the third ventricle can compress the third ventricle and cause hydrocephalus, spreading to both ventricles. Tumors of the posterior cranial fossa, regardless of their location, cause retention and accumulation of cerebrospinal fluid in the aqueduct of Sylvius and in the first three ventricles of the brain. An adjacent tumor the size of a cherry is sufficient to compress the aqueduct of Sylvius. The accumulation of cerebrospinal fluid (hydrocephalus), due to delayed outflow, plays a more significant role in the cause of increased intracranial pressure than the tumor itself.

Clinical picture. Symptoms accompanying intracranial tumors can be divided into general, depending on the increase in intracranial pressure, and local, depending on the direct effect of the tumor on a specific area of ​​the brain.

Common symptoms include headache, vomiting, dizziness, congestive nipple, etc.

Headache is often the initial symptom. The pain spreads throughout the head or may be localized. In the latter case, it occasionally corresponds to the location of the tumor. The pain is intense, sometimes reaches extreme strength and often ends with vomiting.

Vomiting of cerebral origin is not associated with food intake, it occurs on an empty stomach, in the morning, when moving from a horizontal to a vertical position, it occurs immediately and occurs without effort.

With intracranial tumors, the psyche changes, irritability and forgetfulness appear, and attention is focused on the manifestations of the disease. Toward the end of the disease, hibernation often occurs. The face becomes indifferent, mask-like.

An extremely common (up to 80%) and important symptom is a stagnant nipple. A stagnant nipple can exist for several weeks or months without weakening of vision, then optic nerve atrophy and complete blindness occur. A congested nipple is a consequence of cerebral edema spreading to the optic nerve, or a consequence of difficulty in the outflow of blood through the veins of the eye. In cases of brain tumors, especially large brain tumors, nipple congestion may be absent.

There is a slowdown, less often an increase in the pulse, dizziness (which, with the participation of the vestibular apparatus, can also be a local symptom); epileptic seizures, often occurring in the form of Jacksonian epilepsy; progressive increase in cranial volume, determined by systematic measurement, divergence of cranial sutures, especially in children; diffuse thinning of the cranial bones; local thinning of the bones of the vault due to increased pressure of pachion granulations, expressed as spotting on the radiograph; flattening of the sella turcica

Local, or focal, symptoms depend on the location of the tumor.

With tumors of the frontal lobes, the initial symptom is often a mental disorder in the form of mental dullness, weakening of memory, or in the form of euphoria, foolishness, a tendency to make witticisms and funny jokes. When the tumor is located in the area of ​​the third (left) frontal gyrus, where the cortical part of the speech system is located, motor aphasia occurs, i.e., the inability to pronounce words while maintaining the motor ability of the corresponding muscles. When the tumor is located on the lower surface of the frontal lobe, the olfactory bulb is compressed, as a result, the sense of smell on the same side is weakened or lost. There is also a balance disorder.

With tumors in the area of ​​the anterior central gyrus, focal symptoms are especially pronounced. Here, in the upper part of the central gyrus, the motor volitional centers are located. Here the highest analysis and synthesis of motor acts takes place. Compression or germination of the upper part of the gyrus by a tumor leads to the loss of volitional movements of the lower limb, compression or germination of the middle part leads to loss of movements of the upper limb, lower - movements of the cervical, facial, masticatory, pharyngeal and tongue muscles.

The initial stage of tumor development is accompanied by irritation phenomena, namely, seizures, usually in the form of Jacksonian epilepsy. The phenomena of irritation are subsequently replaced by phenomena of oppression, initially in the form of paresis, and then paralysis on the opposite side, individual limbs (monoplegia) or half of the body (hemiplogia) are subject to paresis or paralysis.

When the tumor presses on the posterior central gyrus, in the cortex of which part of the sensitive system of the face and limbs is located, during the period of irritation unpleasant, partly painful sensations (paresthesia) arise; during the period of oppression, sensitivity is lost (anesthesia) on the face, on individual limbs or on the entire half body (hemianesthesia).

Tumors of the posterior parietal region are accompanied by a picture of astereognosia (inability to determine the shape of an object by touch), apraxia (loss of the ability to make appropriate movements) and alexia (loss of the ability to read while maintaining vision), etc.

Encephalography and ventriculography for tumors in the area of ​​the central gyri and parietal lobe gives a picture of collapse of the cavity of the lateral ventricle located on the side of the tumor and displacement to the opposite side of the other lateral and third ventricle (Fig. 21).

The temporal lobes are responsible for the cortical control of the auditory system. Since the cortex of the right and left lobes has a connection with the hearing aids of both sides, if one side is affected, hearing loss does not occur. Auditory hallucinations are sometimes observed.

With tumors located in the left temporal lobe, right-handers experience sensory aphasia (the inability to understand the meaning of words while maintaining hearing).

Tumors in the occipital region, in the cortex of which the analysis and synthesis of visual perceptions occur, cause the same name hemianopia - loss (for example, of the right) halves of the visual fields of both eyes. In the initial stage, visual hallucinations are observed.

Tumors of the posterior cranial fossa are located in the cerebellar hemispheres, in the vermis, in the fourth cerebral ventricle or in the cerebellopontine angle.

Cerebellar tumors are characterized by asynergia and ataxia. Asynergia is the loss of the ability to produce coordinated, appropriate contractions of the muscles of the trunk, limbs and head, for example, when walking, when throwing the leg forward, the body tilts back instead of the usual bending forward. Ataxia is expressed in trunk instability, a tendency to fall forward or backward, and an unsteady gait, reminiscent of a drunken gait. In addition, symptoms of cerebellar tumors are: muscle hypotonia; nystagmus, which appears when turning the head to the side and depends on dysfunction of the vestibular apparatus; congestive nipple; dizziness and vomiting when turning the head, especially when throwing it back; headache concentrated in the occipital region, less often symptoms of damage to some cranial nerves (especially often V, VI, VII and VIII pairs) on the side of the tumor and sometimes symptoms from the pyramidal tracts. In the initial period of development, cerebellar tumors can only manifest themselves as symptoms of increased intracranial pressure.

Tumors of the cerebellopontine angle(the angle between the pons and the cerebellum) are clinically manifested by symptoms from the auditory nerve (from which the tumor often originates, representing a neuroma developed from the fibers of this nerve - tumor acousticus), initially tinnitus, dizziness, then decreased and finally loss of hearing in one ear. Symptoms of irritation and compression of neighboring cranial nerves - auditory, trigeminal, facial and, finally, the cerebellar symptoms described above and symptoms from the pyramidal tracts gradually join.

Pituitary tumors (hypophysis cerebri) are manifested by headache felt in the depths of the orbits, bilateral temporal hemianopsia due to tumor pressure on the chiasm of the optic nerves, expansion and deepening of the sella turcica (as seen on the radiograph), symptoms of compression of the third ventricle (diabetes insipidus or diabetes mellitus). Other symptoms vary depending on the nature of the tumor.

Chromophobic pituitary adenomas, in addition, are accompanied by symptoms of pituitary insufficiency, i.e., infantilism if the disease began in childhood, weakening of sexual functions in the form of cessation of regulation in women and sexual weakness in men if the disease began after puberty in adults, in addition, obesity or, conversely, emaciation and a decrease in basal metabolism.

Chromophilic adenomas are characterized by gigantism, if the disease began in childhood, and acromegaly, which is an enlargement of the distal parts of the limbs, nose, and chin. In adults, the tumor manifests itself as weakened sexual function and general weakness. Less commonly observed are symptoms from the optic nerve that appear in the late stage of the disease.

Tumors of the pituitary tract, occurring predominantly in childhood and adolescence, are manifested by symptoms of increased intracranial pressure, congestive nipples, hypo- and hyperthermia, polyuria, pituitary insufficiency, and compression of the chiasm. X-ray shows flattening of the sella turcica, destruction of the posterior wedge-shaped processes, and deposits of calcareous salts above the sella.

Brain stem tumors when located in the cerebral peduncle, they are accompanied by paralysis of the III and IV pairs of cranial nerves; when the tumor is located in the pons, they are accompanied by paralysis of the V, VI and VII pairs. These nerves are paralyzed on the side of the tumor. At the same time, paralysis of the limbs occurs on the opposite side ( paralysis alternans).

The location of the tumor in the medulla oblongata causes paralysis of the IX, X and XII pairs of cranial nerves on the same side. When the tumor is localized in the fourth ventricle, severe dizziness and vomiting are observed as a result of increased intracranial pressure (hydrocephalus due to overflow of the cerebral ventricular system).

Pineal tumors (gl. pinalis) in children three and four years of age are accompanied by the onset of premature puberty.

The course of intracranial tumors is different and depends on the histological structure of the tumor and its location. Meningiomas, pituitary adenomas, neuromas ( tumor acousticus) and tumors of the cerebral hemispheres progress much more slowly than, for example, glioblastomas and tumors of the posterior cranial fossa. The usually progressive course of intracranial tumors sometimes ends in unexpected death due to respiratory arrest, due to pressure on the respiratory center of the medulla oblongata, especially with tumors of the posterior cranial fossa.

To make a diagnosis of an intracranial tumor, in addition to a neurological examination, a number of additional studies are required, most of which are mandatory.

Radiography makes it possible to recognize tumors emanating from the cranial bones, to see calcareous deposits in psammomas, and thinning of bones in the area of ​​digital impressions ( impressiones digitatae) in the skull (which is expressed by a spotty pattern), dilated veins diploe due to stagnation, divergence of cranial sutures, which is observed in a sharp form in children. The last three signs provide indirect evidence of increased intracranial pressure.

Ophthalmoscopy is mandatory to determine the presence of congestive nipples and optic nerve atrophy.

A lumbar puncture makes it possible to determine intracranial pressure and obtain cerebrospinal fluid for examination. With free communication of the cranial subarachnoid space and the ventricular system with the spinal subarachnoid space, the pressure in the latter with the patient in a horizontal position is equal to the pressure in the former. With intracranial tumors, the pressure in the spinal subarachnoid space is usually increased, sometimes quite significantly. In some cases it remains normal; sometimes lowered. A decrease in pressure is observed when the tumor interrupts or obstructs the communication between the system of the cerebral ventricles and the cranial subarachnoid space, on the one hand, and the spinal subarachnoid space, on the other. A frequent reason for the interruption of communication is the depression of the brain into the foramen magnum in tumors of the posterior cranial fossa. Under these conditions, the cerebrospinal fluid undergoes significant changes. Characterized by an increased protein content with a small amount of formed elements and a yellowish color of the liquid (xanthochromia). These changes are more pronounced, the more difficult the communication between the cranial and spinal spaces is.

Lumbar puncture is contraindicated for tumors of the posterior cranial fossa and for tumors of uncertain location. The removal of fluid from the spinal subarachnoid space, lowering the pressure in it, increases the usual penetration of the brain into the foramen magnum in tumors of the posterior cranial fossa, which can cause death.

For intracranial tumors, a lumbar puncture is made with the patient in a supine position. The liquid is removed slowly, in small quantities.

Encephalography and ventriculography make it extremely easy to determine the location of the tumor. Guided by the bilateral or unilateral filling of the lateral ventricles with air, changes in shape and displacement under the influence of the tumor, it is often possible to make an unmistakable conclusion about the side and location of the lesion. For example, with a tumor located in the right cerebral hemisphere of the brain, the compressed right lateral ventricle is displaced to the left, while the left one is filled with air (Fig. 21).

Encephalography is contraindicated for tumors of the posterior cranial fossa and brain tumors of undetermined location. Ventriculography is contraindicated on the side of the cerebral hemisphere tumor and when the ventricle is displaced by the tumor.

When diagnosing a brain tumor, it is differentiated from a number of diseases: gumma, chronic brain abscess, late post-traumatic hematoma, sclerosis of the cerebral arteries, meningitis.

Treatment. The main treatment method for patients with brain tumors is surgery. Under certain conditions, the radiation method is also used. Each of these methods has its own indications. Due to the steadily progressing course of the disease and the threat of vision loss, surgery should be performed as soon as possible, as soon as the diagnosis is made. To perform the operation, it is necessary to know the localization of the Tumor, the possibility of access to it (depth, position), and the possibility of removal (size, spread). In addition, a satisfactory general condition of the patient is required. The operation does not eliminate decreased vision or existing blindness.

As diagnostic methods developed and surgical techniques improved, new, deeply located parts of the brain became accessible, such as the third or fourth ventricle, quadrigeminal region, and pineal gland.

Brain tumor removal surgery very serious. Its production requires high technology, strict asepsis and special tools.

To determine the projection onto the surface of the skull of certain parts of the cerebral cortex, the location of the two most important cerebral sulci is established: Rolandic and Sylvian. The position of these grooves also determines the position of individual centers of the cerebral cortex. Usually they use the Krenlein scheme (Fig. 22).

To access tumors of the cerebral hemispheres, a fairly large hinged osteocutaneous flap is created. The hole in the skull must be large both to avoid damage to the brain when squeezing it and for ease of examination of adjacent areas. The hole is closed osteoplastically.

For tumors of the posterior cranial fossa, the part of the occipital bone adjacent to the foramen magnum and covering the cerebellum is completely removed (Fig. 23).

The path to pituitary tumors is made either from the nasal cavity or from the side of the calvarium, opening the cranium and lifting the frontal lobe of the brain, which provides sufficient access to the chiasm of the optic nerves and the tumor. Now the second method is preferred, since the first is often complicated by meningitis.

The operation is performed under local anesthesia, which allows the surgeon to work slowly, punctually fulfilling all technical requirements.

Strict asepsis and careful control of bleeding are necessary. Wax is used to stop bleeding from the diploe. From cerebral vessels - hemostatic mosquito clamps, electrocoagulation. Careful handling of the brain mass and especially the brain centers is of great importance. If there is significant blood loss, blood is transfused. In the postoperative period, bleeding with the formation of a hematoma and cerebral edema, causing an increase in intracranial pressure, is dangerous. The hematoma is emptied, and a hypertonic sodium chloride solution is administered intravenously to reduce intracranial pressure. Hyperthermia (up to 40-42°C) sometimes observed in the first two days in the absence of infection depends on irritation of the temperature-regulating nerve centers.

Postoperative mortality ranges from 10 to 25% and depends on the location of the tumor. It is less in tumors of the cerebral hemispheres and greater in tumors of the posterior cranial fossa and pituitary tumors.

As for long-term results, some of those operated on recover completely or with partial defects (vision); a significant proportion experience relapses. The best long-term results are obtained from operations for meningiomas that can be completely removed. As a rule, gliomas that do not have clear boundaries recur.

In case of inoperable brain tumors, to reduce the increased intracranial pressure, which causes great suffering to the patient, a palliative operation is performed - decompressive trephination. For large brain tumors, for decompression, either a large piece of the calvarial bone is removed according to the location of the tumor, or a small hole is created in the temporal bone, thereby opening the dura mater. A decrease in intracranial pressure is also achieved by puncture of the lateral ventricle. For tumors of the posterior cranial fossa, the posterior arch of the atlas is removed to relieve pressure from the medulla oblongata.

X-ray therapy is used for tumors of the brain stem that are inaccessible to surgery, as an additional method of treatment after surgery for unremovable gliomas and especially for tumors of the brain appendage. The most effective effect of radiotherapy (preferably in combination with radiotherapy) is on chromophilic pituitary adenomas.

A brain tumor- intracranial solid neoplasm, a tumor formed as a result of abnormal growth of cells in the brain or in the central spinal canal.

Brain tumors include all tumors inside the skull or in the central spinal canal. They are formed as a result of abnormal and uncontrolled cell division, usually not only in the brain itself, but also in the lymphatic tissues, blood vessels, cranial nerves, meninges, skull bones, pituitary gland and pineal gland (epiphysis). Cells involved in tumor formation are neurons and glial cells, including astrocytes, oligodendrocytes and ependymal cells. Brain tumors can also be transmitted from a cancer located in another organ (metastatic tumors).

Primary (true) brain tumors are usually located in the posterior fossa in children and in the anterior two-thirds of the cerebral hemispheres in adults, although they can affect any part of the brain.