If the formation of the circulatory system is disturbed during embryonic development, then a vascular malformation is formed. This is an incorrect connection of veins and arteries, which manifests itself at puberty. It all starts with headaches, migraines and seizures. In severe cases, children have epileptic seizures.
Definition
The structure of blood vessels is different throughout the circulatory system. Some of them are thicker, some have a muscular wall, some have valves, but they are all connected together in a certain sequence. If for some reason the sequence established by nature is violated, then conglomerates of convoluted vessels, called malformations, are formed.
As a rule, this is a congenital pathology, the causes of which are unknown. It occurs in nineteen out of a hundred thousand newborns each year. Malformations can cause steal syndrome, compress the tissues of the spinal cord and brain, form aneurysms and cause strokes and hemorrhages under the meninges. Most often, complications occur inmiddle age, after forty years.
Classification
There are several forms that a vascular malformation can take. For their systematization, the American classification ISSVA adopted in 1996 is used. Its fundamental difference from other classifications is the division of all anomalies into tumors and malformations.
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Vascular tumors:
- infantile hemangioma (appears in childhood);
- congenital hemangioma;
- fascicular hemangioma;
- spindle-shaped hemangioendothelioma;
- kaposiform hemangioendothelioma;- acquired tumors.
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Malformations:
- capillary (telangiectasias, angoikeratomas);
- venous (sporadic, glomangiomas, Mafucci syndrome);
- lymphatic;
- arterial;
- arteriovenous;- combined.
Malformation of venous vessels
Venous malformation is an abnormal development of veins with their subsequent pathological expansion. It is the most common among all types of malformations. This disease is congenital, but it can manifest itself both in childhood and in adulthood. The location of the altered vessels can be anything: the nervous system, internal organs, skin, bones or muscles.
Venous malformations can be located on the surface or lie in the thickness of the organ, be isolated or stretch over several parts of the body. In addition, the closer they are to the surface of the skin, the more saturated the color becomes.
Because ofunusual shape and color, they can be confused with hemangiomas. For differential diagnosis, it is enough to slightly press on the changed area. Malformations are soft and easily change their color. In case of occurrence of abnormal vessels deep in the human body, the pathology may not manifest itself in any way.
Along with the growth of the child, the malformation also increases, but under the influence of trigger factors, such as surgery, trauma, infection, hormonal drugs, childbearing or menopause, there is a rapid expansive growth of blood vessels.
Chiari malformation
This is a vascular malformation characterized by a low location of the cerebellar tonsils. The disease was described at the end of the nineteenth century by the Austrian physician Hans Chiari, after whom the phenomenon was named. He identified several of the most common types of this anomaly. Due to the low location of the tonsils, it is difficult for the outflow of fluid from the brain to the spinal cord, this creates increased intracranial pressure and provokes the development of hydrocephalus.
Chiari type 1 malformation describes the displacement of the tonsils of the cerebellum downward and pushing them through the foramen magnum. This arrangement causes expansion of the spinal canal, which manifests itself clinically during puberty. The most common symptoms are headache, tinnitus, unsteady walking, diplopia, articulation problems, trouble swallowing, and sometimes vomiting. Adolescents are characterized by a decrease in pain and temperature sensitivity in the upper half of the body andlimbs.
Chiari malformation of the second type develops if the size of the foramen magnum is enlarged. In this case, the cerebellar tonsils do not descend, but fall into it. This leads to compression of the spinal cord and cerebellum, respectively. At the same time, symptoms of fluid stagnation in the brain, heart defects, embryogenesis disorders of the digestive canal and genitourinary system are possible.
Spinal cord
Spinal cord malformation is a rare disease that leads to progressive myelopathy. Arteriovenous malformations prefer to be located between the sheets of the hard shell or lie on the surface of the spinal cord in the thoracic or lumbar regions. More often, pathology occurs in adult men.
The disease in terms of symptoms resembles multiple sclerosis and can mislead a neurologist. A sharp deterioration in the condition occurs after rupture of blood vessels and hemorrhages in the subarachnoid space. Patients have disorders of the sensitive and motor spheres, disturbances in the functioning of the pelvic organs. If cortical symptoms join, then the disease becomes more like ALS (amyotrophic lateral sclerosis).
If a patient complains of two different neurological disorders, the doctor must suspect a vascular malformation and conduct a visual examination of the spine. Signs of the presence of altered vessels will be lipomas and areas of increased pigmentation. Such a person should be sent for an MRI or CT scan. This will verifydiagnosis.
Symptoms
A vascular malformation is like a time bomb or a cocked pistol in the hands of a child - no one knows when the disaster will begin. Despite the fact that the disease is a congenital anomaly, it begins to manifest itself much later. There are two types of course of vascular malformation:
- hemorrhagic (in 70% of cases);- torpid (in the remaining 30%).
None of the options can be called attractive for a person with this diagnosis. In the case of a hemorrhagic course, the patient has high blood pressure, and the vascular node itself is small and is located in the back of the head. Half of people with a hemorrhagic type of malformation have a stroke, which leads to disability or death. The risk of hemorrhage increases with age, and for women, pregnancy and childbirth is an additional factor.
If a person successfully had the first stroke, then with a probability of 1:3 there will be a second hemorrhage within a year. And then the third. Unfortunately, after three episodes, few survive. Approximately half of patients have complex forms of hemorrhage with the formation of intracranial, intrathecal or mixed hematomas and tamponade of the cerebral ventricles.
The second variant of the course is caused by a large vascular malformation lying deep in the cerebral cortex. Its symptoms are quite characteristic:
- convulsive readiness or presence of epileptiform seizures;
- severe headaches;- presence of deficientbrain tumor-like symptoms.
Syncope
Practically all people with vascular malformations located in the brain sooner or later develop syncope (that is, fainting). This is due to a temporary decrease in the volume of cerebral circulation. During syncope, the patient is pale, covered in a cold sweat, his hands and feet are cold, his pulse is weak, and his breathing is shallow. The attack lasts about twenty seconds, and at the end of the attack, the patient does not remember anything.
Every year there are more than half a million new cases of syncope, and only a small fraction of them have a clear causal relationship. Syncope can be caused by excessive irritation of the carotid sinus, trigeminal or glossopharyngeal neuralgia, dysregulation of the autonomic nervous system, cardiac arrhythmias, and, of course, vascular malformations. Abnormal arteries and veins provide shunting of blood and acceleration of its blood flow. Due to this, the brain does not receive enough nutrition, which is manifested by impaired consciousness.
Complications
Even before the malformation manifests itself clinically, a person will secretly develop irreversible pathomorphological phenomena. This is due to hypoxia of the brain tissue, its degeneration and death. Depending on the location of the affected area, characteristic focal symptoms are observed (disturbances in speech, gait, voluntary movements, intelligenceetc.), there may be epileptic seizures.
Severe complications begin already in adulthood. Abnormal vessels have a thin wall and are more prone to rupture, so ischemic strokes are more common in patients with malformations. Large conglomerates of arteries and veins compress the tissues around them, causing hydrocephalus. The most dangerous is hemorrhage as a result of rupture of several vessels at once. This can either have lethal consequences or end with almost no consequences. It all depends on the amount of blood shed. Hemorrhagic stroke has a much less promising prognosis and may recur over time.
Diagnosis
Initial neurological examination may not reveal any abnormalities in people with vascular malformations. As a rule, a targeted and very thorough examination is required to identify violations. If a patient complains of frequent severe headaches, tremors, intermittent disturbances in consciousness, and impaired vision or gait, then this is a reason to send him for neuroimaging. Simply put, on a computer or magnetic resonance imaging of the brain.
Contrast angiography shows the most detailed and accurate structure of the vessels. To do this, the patient is injected into the common carotid artery with a radiopaque fluid and a series of images is taken. This method has a number of complications and side effects, so it is used only in case of difficulty in making a diagnosis.
To view speed, direction and levelblood flow in the altered area, Doppler ultrasound is used. This method allows you to see the shunt of blood between arteries and veins, determine the type of vessels, determine the presence of aneurysms and other complications.
Treatment
Can a vascular malformation be corrected? Treatment methods depend on the type of anomaly, its location, the size of the focus and the presence of a history of strokes.
There are three main methods of therapy:
- open surgery;
- minimally invasive embolization;- non-invasive radiosurgical treatment.
For each of them there are indications, contraindications and a list of possible complications.
The most traumatic is an open operation. In order to get to the focus, the skull is opened, the vessels are clipped and crossed. This option is possible if the malformation is located on the surface of the brain and is small. Attempts to reach a deep-seated focus can result in damage to vital centers and death.
What can be done if the patient has a deep malformation? Treatment consists of endovascular embolization. This is a rather gentle procedure, during which a thin catheter is inserted into a large vessel that feeds the abnormal conglomerate and, under X-ray control, the doctor gets to the malformation. Then a hypoallergenic drug is injected into the lumen of the vessels, which fills all the available space and coversblood flow in this area. Unfortunately, this technique does not give an absolute guarantee that the vessel is completely obliterated. Therefore, it is most often used as an additional treatment.
The most advanced method of treating vascular malformations is considered to be cyber-knife surgery (radiosurgery). The essence of the method is to process the anomalous focus from different points with narrow radioactive beams. This allows you to quickly destroy the altered vessels without damaging he althy tissues. The process of sclerosis of blood vessels on average takes several months. The advantage is the complete absence of complications from the nervous system. But there are limitations for using this method:
1. The total diameter of the vessels should not exceed three centimeters.2. There should be no history of strokes or other hemorrhages. Since the thin wall may not withstand and break in the interval between the procedure and the final sclerosis of the malformation.
