Intracranial pressure, intracranial hypertension: clinical aspects. What are the types of edema in dogs?

Meningioma is the most common brain tumor in dogs. It affects the system of membranes surrounding the brain and spinal cord. This system is called the meninges. The tumor begins to put pressure on adjacent areas, spreading to them. All breeds of dogs are susceptible to meningiomas, however, this disease is most often observed in dogs over seven years of age.

Meningioma in dogs

Meningioma is the most common brain tumor in dogs. It affects the system of membranes surrounding the brain and spinal cord. This system is called the meninges. The tumor begins to put pressure on adjacent areas, spreading to them. All breeds of dogs are susceptible to meningiomas, however, this disease is most often observed in dogs older than seven years.

Symptoms

Symptoms vary depending on the location of the tumor, but some common symptoms include:

Seizures

Visual impairment

Abnormal behavior or mental condition

Impaired coordination of movements

Back or neck pain

Causes

The causes of meningioma have not yet been established.

Diagnostics

The veterinarian will ask you to provide full story your pet's illnesses, describe the symptoms and tell when exactly they began to appear. Then the doctor will examine the animal and prescribe a urine test, general and biochemical analysis s blood. Test results are usually within normal limits. For further testing, your veterinarian will take a sample of your pet's cerebrospinal fluid, which circulates around the brain and spinal cord, protecting and nourishing them.

Magnetic resonance imaging and computed tomography- two most effective methods for determining pathological changes and their locations. Your veterinarian may also do a biopsy to make a full diagnosis.

Treatment

For complete healing it is necessary surgery to remove a tumor, but this is not always possible. Sometimes the tumor is in an inaccessible place or cannot be completely removed due to its invasiveness. In such cases it is recommended radiation therapy. Besides, infusion therapy, special diet and medications will help keep the pathology under control and stabilize the dog’s condition.

The overall prognosis depends on the outcome surgery. Most dogs whose tumors are successfully removed have a good chance of recovery.. However, some animals continue to get sick due to tumor penetration into other tissues or other complications.

You'll have to Take your pet to the vet regularly to monitor the course of the disease and the effect of medications. During the postoperative period, dogs feel unwell. To relieve pain, veterinarians prescribe painkillers that are needed use with extreme caution to avoid overdose. During the recovery period, try to provide the dog with peace and protect it from children and other animals. The dog may need to be crated to limit physical activity.

Cerebral edema is a pathological condition accompanied by the accumulation of fluid in the brain tissue.

Reasons for the development of cerebral edema

• traumatic brain injury;
• brain tumor;
• cerebral stroke (ischemic, hemorrhagic);
• inflammatory processes in the brain and membranes (encephalitis, meningitis);
• somatic diseases(cardiovascular pathology, severe infections, burn disease);
• allergic reaction ( anaphylactic shock);
• intoxication (alcohol, drugs).

• oxygen starvation of the brain;
• increased concentration carbon dioxide in the blood;
• low protein content in blood plasma;
• electrolyte imbalance.

Clinical picture, symptoms of cerebral edema

Cerebral edema can be local and widespread (generalized). Clinical manifestations of cerebral edema are varied and depend on the duration, localization, prevalence, and severity of the pathological process.

With cerebral edema, there are 3 main groups of symptoms:

• symptoms associated with intracranial hypertension;
• focal symptoms;
• stem symptoms.

Increased intracranial pressure is indicated by a bursting headache, nausea, vomiting, decreased level of consciousness.

Intracranial hypertension can lead to the development of seizures.

Focal symptoms are loss of certain functions. When cerebral edema is localized in certain areas, the function of these areas will be disrupted, so those functions for which the affected area is responsible will be lost.

TO focal symptoms include paresis, paralysis, impaired sensitivity, vision, speech disorders.

When the cerebellum is damaged, balance and gait disturbances occur.

The brain stem contains the vital centers for breathing and heartbeat. If cerebral edema affects this area, cardiovascular disorders develop, breathing and thermoregulation are impaired, reflexes fade and the level of consciousness decreases, seizures.

Diagnosis of cerebral edema is based on the patient’s complaints (if the patient is conscious), examination data, assessment of the neurological status, results additional methods examinations.

During a neurological examination of the patient, attention is paid to unconditioned reflexes, loss of functions, disorders various fields.

When examining the fundus of the eye, which is carried out by an ophthalmologist, it is possible to determine swelling of the optic nerve nipples - one of the symptoms of cerebral edema.

To assess concomitant pathology affecting the course of cerebral edema, it is necessary to conduct laboratory methods research. Need to carry out general analysis blood, determine the level of protein, electrolytes (potassium, sodium, magnesium, chlorine) in the blood plasma.

If cerebral edema is suspected, a spinal puncture, angiography of cerebral vessels, and computed tomography or magnetic resonance imaging of the brain are performed.

Computed tomography or magnetic resonance imaging of the brain will help determine the size and location of cerebral edema.

The list of additional research methods performed can be expanded depending on the leading cause of cerebral edema.

To eliminate hypoxia, it is necessary to carry out oxygen therapy - the artificial introduction of oxygen into the body through the respiratory tract.

For cerebral edema, local hypothermia is a simple and effective treatment. To do this, cover your head with ice packs or other sources of cold.

Helps drain excess fluid from brain tissue intravenous administration hyperbaric solutions (10% sodium chloride solution, 40% glucose solution).

The use of medications that have a diuretic effect helps eliminate cerebral edema. Furosemide, Lasix, magnesium sulfate, urea, mannitol are prescribed.

To reduce vascular permeability and prevent further progression of edema, glucocorticosteroids (prednisolone, dexamethasone) are prescribed.

If the swelling has spread to the trunk area, maintenance is necessary normal temperature body and vital functions - breathing and heartbeat.

In some cases the only way saving the patient's life is surgery- craniotomy.

Complications and consequences of cerebral edema

The most dangerous complication of cerebral edema is death due to damage to vital centers located in the brain stem.

IN long term swelling of the brain can cause dementia (dementia).

Brain edema, like other organic brain pathologies, can become the basis for the development of depression.

In the presence of pathologies that can lead to cerebral edema, diuretics (furosemide, magnesium sulfate) are prescribed. These medicines prevent the accumulation of excess fluid in the brain tissue and prevent the development of cerebral edema.

Swelling is abnormal excessive accumulation fluids in the tissues that surround the body's cells.

There are two types of edema in dogs:

1. peripheral (edema subcutaneous tissue and skin),
2. internal (edema of the brain, lungs, etc.)

Peripheral edema is noticeable to the naked eye. It can occur in one place or spread throughout the body. Internal swelling can only be recognized by certain symptoms. Edema itself is not a disease, but a symptom of some disease.

It indicates that excess fluid has come out of the vessels. Therefore for successful treatment it is necessary to look for the cause of the swelling.

Causes of edema in dogs

Local asymmetrical swelling in different parts of the body can occur due to local inflammation due to infection, an allergic reaction, injection of large amounts of fluid, compression of a limb, bites of poisonous animals, or as a reaction to medicinal substances.

In older dogs, they can occur as a result of arthrosis of the limbs, which worsens with increasing physical activity. Angioedema may occur on the neck and face as a reaction to food or chemical intoxication, as well as to a reptile or insect bite. This is very dangerous condition, as a result of which the dog is urgently needed.

Symmetrical edema indicates a deterioration in venous outflow as a result of heart failure and increased hydrostatic venous pressure. They occur when the oncotic pressure of the blood decreases as a result of protein loss due to kidney disease (glomerulonephritis, amyloidosis, nephrotic syndrome), prolonged bleeding, enteropathies.

The reason may also be a decrease in protein formation during fasting and liver disease (cirrhosis), an increase in capillary permeability during intoxication, infections, etc.

Treatment of edema can only be symptomatic, aimed at quickly alleviating the animal’s condition. It depends on the nature of the edema, so it is very important to recognize its cause and treat the underlying disease. If swelling is the result of injury or local inflammation, then antiseptics and antibiotics are most often used.

Chronic joint damage (arthrosis) can lead to swelling of the tissues of the joint and paw under significant load. If swelling occurs at the site of the insect bite, but the general condition of the animal has not worsened, it is enough to treat the bite site with an antiseptic. Angioedema on the face or neck is a symptom of allergies. Antihistamines such as suprastin and diphenhydramine are rarely effective for dogs.

First aid is to restore patency respiratory tract with the help of adrenaline. Steroid hormones (dexamethasone or prednisolone) are also used, which suppress allergic reactions at all stages. For symptoms of angioedema (sudden swelling of the muzzle, redness or blanching of the mucous membranes oral cavity, rapid breathing, ) it is especially important not to experiment with drugs, but to take the animal to the clinic as quickly as possible.

Edema due to low blood albumin levels is diagnosed by measuring the level total protein and albumin (biochemical blood test). Low albumin levels can be corrected with proper nutrition and intravenous administration. human albumin. This type of peripheral edema is only a symptom and if there are no additional symptoms that indicate protein loss in the body (and malnutrition), then research is necessary internal organs(kidneys, liver): ultrasound, biochemical blood test, general urine test.

In the fight against peripheral edema, transfusion of colloidal solutions (infucol, refortan) and careful use diuretics. For edema associated with impaired renal function, diuretics (aminophylline, furosemide), as well as glucocorticoids and a salt-free diet are prescribed.

Introduction

Malignant brain tumors (MBTs) have a number of features that distinguish them from tumors of other locations.

Firstly, most AMCs are characterized by the absence of lymphogenous and hematogenous metastasis beyond the central nervous system. The spread of the tumor occurs mainly along the meninges, liquor pathways of the brain and perivascular spaces.

Secondly, OGM is characterized by special severity clinical symptoms. The relatively small volume of the animal’s skull, the spread of the tumor in the vital important structures brain lead to the rapid development of a rather complex clinical picture, aggravated by hypertension syndrome due to cerebral edema and occlusion of the ventricular system.

Thirdly, the development of certain symptoms of the disease is largely determined by the localization of the primary tumor, the direction of its growth, the nature of its involvement in pathological process adjacent brain structures.

Treatment of malignant GMOs is complicated by a number of factors. These include the resistance of most tumors to drugs traditional therapy, infiltrative spread into the brain parenchyma, limited penetration medicines into tumor tissue through the blood-brain barrier. Tumors of a high degree of malignancy, as a rule, have high proliferative activity.

Diagnostics

The objects of the proposed study were dogs and cats with brain tumors, patients of the veterinary clinic of neurology, traumatology and intensive care (St. Petersburg) from 2004 to 2009. These are: 64 dogs from 6 months to 15 years and 9 cats from 5 to 13 years. Animals with possible metastases of mammary gland tumors (MG) and other neoplasms were not taken into account. All patients were examined according to standard clinical methods, including taking anamnesis, neurological examination and X-ray, ophthalmological, electroencephalographic and echoencephaloscopic studies (in dwarf dogs). Then, to decide on surgical intervention, the patients underwent magnetic resonance imaging ( MRI) of the brain, since this particular research method is the most preferable for making a diagnosis and clarifying the localization of a tumor, and is currently an important component of preoperative assessment and diagnosis in patients with brain tumors (Herzog RJ., Guyer RD., Graham- Smith A., Simmons ED Jr., 1995; Hilterhaus F., Draf W., Hoererhalt, Liang L., Korogi Y., Sugahara T., 2002). Additional diagnostic procedures, if necessary, included computed tomography to assess changes in the skull bones and cerebral angiography.

Based on the results of the studies, it was found that the most common brain tumors in dogs are astrocytoma, oligodendroglioma, meningioma, glioma, and ependymoma. Meningioma, astrocytoma, and glioma were most often diagnosed in cats.

Suggested treatment

Treatment tactics depend on the degree of malignancy of the tumor. One of the dominant Lately approaches available in veterinary clinic, is surgery combined with chemotherapy. In some cases, only drug treatment is used.

Main view surgical intervention is a craniotomy aimed at removing the tumor and providing intracranial decompression. The extent of surgical resection is mainly influenced by the location of the tumor. For example, tumors of the frontal lobe can be removed almost completely, and meningiomas, which are usually located outside the brain (while tumors of other locations spread to subcortical structures brain), are not subject to radical removal. The results of surgical treatment of dogs with gliomas are especially unsatisfactory. III-IV degrees anaplasia. Taking into account the infiltrative growth of the majority of brain tumors and the involvement of functionally and vitally important parts of the brain in the tumor process, the use of exclusively surgical method treatment. The latter circumstance is aggravated by the fact that surgical intervention in some cases can cause complications that lead to death.

Modern technologies can significantly improve the safety and effectiveness of neurosurgical interventions. These are methods of preoperative and intraoperative visualization. Unfortunately, most brain tumors differ little from brain tissue, and therefore it is necessary to ultrasound examination at the time of the operation in order to determine the localization and radicality of the operation performed. The maximum possible surgical removal of the tumor in an adequate functionally acceptable volume significantly improves the quality of life of patients in this category and allows increasing the time reserve for therapy. It should be noted that surgery is, of course, an important component of the treatment of brain tumors, providing an immediate and significant reduction in the mass effect. In most cases, achieve any significant therapeutic effect without carrying out surgical removal tumors is impossible.

To summarize, it should be stated that the problem of treatment malignant tumors brain, despite the achievements of modern veterinary medicine, has not yet been resolved. Increasing the radicality of surgical interventions, the use of pre- and intraoperative visualization improves results surgical treatment, but do not lead to the final recovery of patients. (Cheremisin V.M. et al., 1995; Cherenkov V.G. et al., 1998; Loshakov V.A., 2003).

Of the 64 dogs examined at the clinic, 15 animals were operated on. Of these, one patient died during the operation, and five animals died in the early postoperative period. Less than six months Five dogs survived after surgery (in two, the cause of death was not directly related to a brain tumor: one died four months later from pneumonia, the other was euthanized at the request of the owners). Two patients lived more than six months after surgery. Two more patients continue treatment.

Diagnostics and surgery brain tumors is one of the pressing problems of modern veterinary neurosurgery and requires further research. To do this, we need to create an association or society of veterinary neurologists in our country. It is also necessary to recognize veterinary neurology as a separate science or discipline and introduce its teaching in Russian universities.

Clinical examples of brain tumors

Clinical example of a brain tumor in a dachshund

A 7-year-old dachshund was admitted to the clinic with symptoms of seizure ataxia. The diagnosis was made on the basis of MRI. An operation was performed to remove the tumor.

Clinical example of a brain tumor in a boxer dog

Boxer, male, 6 years old, was admitted in a state of status epilepticus. Electroencephalography (EEG) and MRI were performed for diagnostic purposes. An operation was performed to remove the tumor (according to the histology results - oligodendroglioma).

Patient: boxer. Brain tumor before surgery.

Date of examination: 07/30/2009

Mounting: Monopolar 8

Background recording

The alpha rhythm is not registered over both hemispheres.

Over both hemispheres there is a low-frequency beta rhythm with a frequency of 14-20 Hz with an amplitude of up to 27 µV on the left (up to 21 µV on the right).

A high-frequency beta rhythm with a frequency of 20-35 Hz with an amplitude of up to 45 μV on the left (up to 31 μV on the right) is observed over both hemispheres.

The beta rhythm dominates in the central (C3A1, C4A2) leads.

The predominance of delta rhythm in the frontal leads.

Beta rhythm asymmetry.

A - spectrum amplitude, μV/s; S - spectrum power, μV^2/s^2; F - frequency, Hz; Rhythm index -%

The electroencephalography method can help in making a diagnosis, and can also serve as a method for monitoring treatment and a prognostic method before and after surgery.

Ultrasound diagnostics during surgery modern conditions veterinary operating room is one of the few possible methods visualization of the tumor during surgery. Allows you to reliably distinguish brain tissue from tumor tissue and control the completeness of tumor removal.

Clinical example of removal of a cerebellar tumor from the wall of the fourth ventricle

Dog, 7 years old, Staffordshire Bull Terrier breed. Neurological diagnosis: bulbar palsy, ataxia, nystagmus. According to MRI, there is a neoplasm of the cerebellum.

In cases where, according to MRI, the neoplasm borders on the ventricles of the brain, especially the 4th ventricle, ventriculoscopy can be performed to visualize the tumor in more detail.

Clinical example of removal of meningioma in the cerebellar region of a cat

Cat, 7 years old, with symptoms of ataxia and nystagmus. When conducting conservative treatment with the use of mannitol and dexamethasone, a temporary decrease in neurological symptoms was observed.

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Sotnikov V.V.

Veterinary clinic of neurology, traumatology and intensive therapy, Russian Federation, Saint-Petersburg.

Intracranial brain tumors occupy a fairly small place in the structure of all neoplasias of small domestic animals. But despite the low incidence of this group of diseases, it is necessary to take into account the possibility of tumor damage to the brain in animals with neurological disorders and deficits.

Epidemiology

Classification

Table No. 1. Classification of intracranial tumors.

Tumors from surrounding tissues

Clinical signs

Table No. 2. Possible clinical signs of intracranial tumors in
depending on location.

Diagnostics

1. Routine hematological and biochemical research to exclude extracranial causes (uremia, etc.), concomitant diseases.
2. X-ray of the skull to detect osteolysis or hyperostosis of the skull bones, which is typical for meningioma in cats, a primary neoplasm of the nasal cavity and paranasal sinuses, or a neoplasm of the skull bones.
3. Survey radiography chest and abdominal cavity to identify primary neoplasms and related diseases.
4. Ultrasound of the chest and abdominal cavity to detect the primary tumor and diagnose concomitant diseases.
5. Analysis of cerebrospinal fluid for diagnostic purposes inflammatory diseases brain, which is very important for differential diagnosis. Precipitation methods are preferred. In some cases, this allows you to detect atypical cells. This method can also be used to diagnose neuroleukemia. Spinal tap in such animals should be carried out with extreme caution. With increased intracranial pressure there is a danger of brain wedging in case of sharp fall pressure. Possible measures to prevent such a complication are slow drainage of cerebrospinal fluid, pre-infusion of mannitol, and hyperventilation.
6. Electroencephalography. This diagnostic method for tumor lesions of the brain is based on the fact that, as a rule, tumor tissue is electrically neutral. Such changes in the electroencephalogram may provide grounds for further diagnostics in the direction of searching for brain neoplasia.
7. Magnetic resonance imaging (MRI) to determine the size, shape and exact location of the tumor and suggest the type of tumor (Table 3). MRI has significant advantages over computed tomography(CT): better visualization of intracranial soft tissues, the ability to differentiate more subtle changes in tissues (edema, vascular changes, hemorrhages and necrosis).
8. Biopsy. Intravital biopsy is quite complex and not feasible in all cases. For a biopsy, it is necessary to know the exact location of the tumor, so a biopsy is performed only after an MRI. The possibility of performing a biopsy depends on the location of the tumor and the general status of the animal. Often a biopsy is performed only postmortem.

Table No. 3. Presumptive diagnosis of brain tumors by
MRI data.

Supportive and symptomatic treatment includes anticonvulsant therapy (phenobarbital 2-4 mg/kg orally every 12 hours) and corticosteroid therapy (methylprednisolone 10-15 mg/kg).

Forecast

conclusions

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