Magnetic resonance imaging (MRI) is one of the most informative methods for diagnosing diseases. It acquires special diagnostic value in neurological practice. After all, it is with the help of MRI of the vessels of the brain and neck that it is possible to diagnose pathologies of the organs of the central nervous system (CNS) already in the early stages. Read more about this survey method in the article.
The essence of the procedure
With the help of MRI angiography of the vessels of the brain and neck, you can see the structure of the arteries of the central nervous system, their shape, location, and so on.
This is possible due to the existence of the principle of magnetic nuclear resonance. Its essence lies in the fact that the magnetic field inside the tomograph causes the oscillation of hydrogen ions. The energy that is generated in this case is captured by sensors, which leads to the formation of a clear image oncomputer monitor.
Even more informative method - MRI of the vessels of the brain and neck with contrast. It involves the intravenous administration of a contrast agent based on gadolinium. This makes the vessels visible even better.
What diseases are diagnosed by MRI?
What does an MRI of the vessels of the head and neck show? Using this research method, it is possible to establish the exact localization of circulatory disorders in the brain and cervical spine.
If you do an MRI without contrast, which is a more economical method, you can determine the following pathologies:
- artery aneurysm - a sac-like protrusion of a thinned vessel wall;
- vasculitis - inflammation in the vascular wall;
- the place of blockage of the vessel by a thrombus or embolus, which leads to circulatory disorders of distal obstruction (ischemia);
- cysts of the brain and spinal cord;
- neoplasms of the brain and spinal cord;
- impaired blood flow in the carotid artery - the main artery that supplies blood to the head and brain, in particular.
Contrast-enhanced MRI of the vessels of the head and neck improves the diagnostic value of the method. With the help of this examination, it becomes possible to accurately determine the location and size of the tumor, the intensity of its blood supply. And this, in turn, makes it possible to judge its malignancy. Malignant tumors are more intensively supplied with blood.
Also, the introduction of contrast makes it possibleestablish the degree of slowing down or acceleration of blood flow in the vessels. Contrast MRI is done before surgery. This is necessary to evaluate the effectiveness of the operation.
Indications for the procedure
MRI angiography of the vessels of the head and neck is done according to strict indications. These include:
- suspected cerebral atherosclerosis - accumulation of fat on the inner walls of cerebral vessels;
- suspicion of the development of a stroke - an acute violation of blood flow in the vessels of the brain;
- suspicion of the presence of vascular malformations - congenital disorders of the structure of blood vessels;
- accidental stenoses of cervical vessels detected by ultrasound;
- dyscirculatory encephalopathy - a chronic disorder of cerebral circulation;
- as a control of the effectiveness of surgery on the cerebral vessels or arteries of the neck;
- suspicion of neoplasms of the neck or brain.
Contraindications
Contraindications to MRI are divided into absolute and relative. In the presence of absolute contraindications, this procedure is strictly prohibited. In the second case, an MRI of the vessels of the head and neck remains acceptable if the expected benefit outweighs the possible negative consequences.
Absolute contraindication is the presence of any metal objects on the human body or inside the body:
- pacemaker;
- prosthetic joints;
- insulin pump;
- metal clips on vessels;
- dentures and more.
The presence of metal not only spoils the quality of the image, but can also lead to damage to the scanner.
Relative contraindications include the following conditions:
- pregnancy and breastfeeding;
- under 7;
- mental illness;
- claustrophobia;
- serious kidney dysfunction;
- a serious condition of the patient, in which there are difficulties in transporting him to the MRI room.
- hyperkinetic disorders are a group of neurological diseases that are manifested by involuntary movements of the limbs or torso.
Preparing for the procedure
MRI without contrast does not require specific preparation. But if a decision is made to do an MRI of the vessels of the brain and neck with contrast, you should follow a few rules:
- Do not eat 8 - 10 hours before the examination, as nausea or vomiting may occur during the administration of the contrast.
- If you are allergic to the contrast, you should tell your doctor about it.
- You should also warn the doctor about kidney disease, if any. Severe renal dysfunction impairs the excretion of contrast from the body.
Immediately before the examination, an allergic test is performed. This is done by subcutaneous injection of a small amount of contrast. After that, the nurse observes the reaction of the skin. The presence of redness, itching, burning or rash indicatesincreased sensitivity of the body to contrast. In such cases, it will have to be abandoned.
Carrying out the procedure
Tomograph consists of a large round machine and a table. The patient is placed on the tomography table in the supine position. Hands and feet are tied, and the head is fixed. This is a necessary measure to keep the patient still.
The table slides into the scanner, and it starts to read the image. During operation, the device produces an unpleasant grinding or tapping, so the patient is often given earplugs.
The doctor is constantly in the next room, which is separated by a glass partition. During the entire procedure, he maintains contact with the patient. So don't worry.
If there is a need for contrast, it is injected even before the table is pushed into the scanner.
On average, a classic tomogram lasts up to 40 minutes, and with the introduction of a contrast agent - up to an hour and a half.
Interpretation of results
After examining the images by the diagnostician, he makes a detailed description of everything he saw in the picture. The doctor characterizes the structure and shape of the arteries, characterizes the blood flow, the ratio of blood vessels to surrounding tissues. The structures of the brain or neck are also described.
Next, a preliminary diagnosis is made. But the final clinical diagnosis is made by the attending physician. For this, an integrated approach is used. The doctor evaluates not only the conclusion of the MRI of the vessels of the brain and neck, but alsoclinical data, results of additional examination methods.
Afterward, the specialist makes recommendations to the patient and prescribes the appropriate treatment.
Treatment of identified diseases
Treatment of brain and neck vascular diseases detected on MRI directly depends on their type. All therapy can be divided into two groups: medical and surgical.
Drug treatment is aimed at improving blood flow in the cerebral vessels and preventing cerebral edema. So, in acute and chronic disorders of cerebral circulation, the following groups of drugs are prescribed:
- diuretics - Furosemide, Torsid;
- decongestants - "L-lysine aescinate";
- anticoagulants and antiaggregants - "Aspirin", "Heparin", "Warfarin" - to prevent blood clots;
- nootropics - "Cerebrolysin", "Piracetam" - to improve metabolism in brain cells.
Inflammatory diseases of the walls of blood vessels (vasculitis) are most often autoimmune in nature. Therefore, treatment is aimed at suppressing the immune response. For this, corticosteroids "Prednisolone", "Methylprednisolone", cytostatics "Azathioprine", "Cyclophosphamide" are used.
In congenital disorders of the structure of the vascular wall (malformations), treatment is aimed at surgical elimination of the problem. In this case, the operation can be performed as a neurosurgeon (withmalformations of cerebral vessels), and a vascular surgeon (with anomalies in the structure of the vessels of the neck).
MRI or ultrasound?
Doppler ultrasound (USDG) is a method of studying blood vessels using ultrasonic waves. Using this method, you can also see the blood flow in the vessels of the head and neck. What is better - MRI or ultrasound of the vessels of the head and neck?
Although MRI is considered the most informative way of making a diagnosis, it has a number of limitations that ultrasound does not:
- need to be stationary for a long time;
- the patient must be free of any metallic objects in the body;
- may develop an allergic reaction to the contrast agent;
- results are not visible immediately, but after a few hours, and the ultrasound picture can be observed on the monitor in real time;
- high cost of procedure (3-4 times more expensive than ultrasound).
MRI and ultrasound of the vessels of the head and neck in most cases complement each other. An MRI is often done to confirm ultrasound findings.
It can be concluded that MRI is the method of choice for disorders of blood flow in the vessels of the head and neck. But if there are contraindications to this method or there are monetary restrictions, ultrasound can also be informative.
