Ultrasound of the brain – in which cases this study may be prescribed
- 1 Characteristic
- 2 Indications
- 3 Dopplerography
- 4 Duplex scanning
- 5 Triplex scanning
- 6 Transcranial
- 7 Neurosonography
- 8 Fetal ultrasound
- 9 How to prepare for ultrasound of the brain
- 10 Ultrasound
- 11 Features of the children
- 12 Decryption
- 13 Contraindications
Devices for ultrasound diagnosis are now in every clinic and medical center, and therefore this type of examination is available for many patients.
Ultrasound examination of cerebral vessels is one of the most common diagnostic methods today. The basis is the reflection of the ultrasound wave from the area under study. It is used to detect anatomical pathologies of the vertebral, basilar, carotid arteries, anterior and internal jugular veins, subclavian artery and vein, facial vein. Ultrasound of cerebral vessels shows the diameter of the lumen, internal formations, the state of the surrounding tissues.
The procedure, supplemented by Doppler, allows you to detect areas of blood vessels with impaired blood flow due to their narrowing, blockage, tumors. With its help, the functioning of the circulating paths of the blood flow is checked, and the treatment carried out and the results of the surgical intervention are monitored.
Today, the doctor, giving direction to ultrasound diagnostics, separately indicates the type of study: ultrasound, Doppler, duplex, triplex or transcranial. In most cases, simple ultrasound does not, and combine it with Doppler in order to obtain a complete anatomical and functional picture.
The advantages of ultrasound diagnostics include safety, non-invasiveness, painlessness, good quality of the information received, breadth of use, low price. It is also important that the study does not need to introduce a contrast agent and irradiate the patient. In addition, the USDG gives a picture in real time.
There are research and drawbacks: it is easy to learn about the state of large vessels with it, but small branches can be hidden behind the bones of the skull. This prevents you from getting the full picture. The deposition of calcium salts in atherosclerosis also makes it difficult to obtain accurate information. Difficulties arise when carrying out the procedure in obese people. When conducting transcranial triplex scanning of cerebral vessels, the quality of the information received may deteriorate due to the specific equipment.
Ultrasound scans are scheduled and performed on a regular basis by people over 40, patients who have a sedentary lifestyle, are prone to strong emotional stress, depression, and often under stress. The regularity of the examination is also important for those who have undergone an operation, and who the following diseases are suspected or already diagnosed:
- circulatory problems in the brain;
- head injuries;
- cervical osteochondrosis;
- arterial hypertension;
- neoplasms in the head or cervical spine;
- previous diseases associated with inflammatory processes;
An indication for ultrasound diagnosis is the appearance of such disorders as persistent headaches, dizziness, darkening of the eyes, tinnitus, weakness, tingling, numbness in the hands and feet. Among other important reasons: loss of consciousness, which happened even once, impaired speech, vision and hearing, attention, performance, memory. Necessarily ultrasound is performed before surgery on the brain or heart.
This study performs only one function – determining the flow rate of blood and its direction. On the monitor there is a graph with the results of the study. There are no vessels for visualization.
Directly Doppler of the brain allows to obtain the following information about the vessels:
- elasticity of the walls;
- characteristic of the internal cavity;
- violation of the integrity of the walls;
- education inside the lumen;
- change of course;
- branch branches in the wrong place.
Duplex scanning of cerebral vessels is an ultrasound examination that combines a two-dimensional picture – the anatomical structure of the vessels, the tissues around them and the speed of blood flow. With this method, atherosclerotic plaques, blood clots in arteries and veins are found, and the state and integrity of the vascular wall is checked.
An extracranial study aimed at checking the main arteries and scanning that studies intracranial vessels located in the skull are identified. During the procedure, the common carotid arteries are examined along the entire length, the internal carotid arteries before entering the skull, and the partially external carotid and vertebral arteries.
Duplex scanning of the head and neck vessels allows diagnosing the disease at an early stage of development.
The results of intracranial and extracranial triplex scanning of arteries and cerebral veins reflect their anatomical structure. The blood flow is presented in color, depending on the speed at a particular site. Depending on the subject of study – a vein or artery, the image is colored blue and red.
This is not a separate method of research, but an extended duplex scanning of cerebral vessels with an additional function. Vessels are viewed in two longitudinal and one transverse planes.
Transcranial dopplerography of cerebral vessels is a type of duplex research. Its main purpose is to study the speed and direction of blood flow in intracranial vessels. The goal is to identify hematomas, large lesions and control of previously detected disorders. Inspect the walls of blood vessels located in the skull, it is impossible. Information about the structure and lumen of the artery is available only in color mode, the change of which depends on the speed of blood flow.
In transcranial duplex scanning, cerebral vessels can be seen in two planes.
TCD of cerebral vessels is indicated in the following cases:
- Found indirect signs of damage to the arteries in the skull.
- Identified symptoms of cerebral ischemia, the causes of which are unknown.
- A duplex scan of brain vessels showed signs of stenosis and blockage.
- Constant headaches.
- The patient has a complex vascular disease leading to impaired cerebral circulation.
- With the pathology of the brain, which leads to deformation of blood vessels and impaired blood flow.
TKDS is carried out only after duplex. The sensor is located on the temple, neck or eye socket.
A separate type of ultrasound, aimed at checking the pathologies of the brain of the newborn, is neurosonography. Recently, in many maternity hospitals, this examination is carried out before the baby is discharged, and the pediatrician or neuropathologist prescribes it when the baby is 1 month old or if indicated.
Be sure to spend it if the child was born prematurely, at birth received on the Apgar scale less than 7/7 points, there are suspicions of hydrocephalus, cerebral palsy, defects or developmental delay, intrauterine infections, genetic pathologies or diseases of the nervous system.
Another group of indications for neurosonography is prolonged or, conversely, fast delivery, birth trauma, rhesus conflict, and tracking the dynamics of treatment of the baby.
Currently there are 4 types of research:
- Excessive NSG is carried out through a large spring. This technique provides a complete examination of the brain cavity, and therefore is the most common. However, they spend it only up to a year – by this time the spring is usually closed. The most informative examination is immediately at birth or within the first few months.
- When conducting a transcranial USG data is obtained through the temporal, and sometimes the parietal bones.
- The combined method includes examination through the fontanel and bones of the skull.
- USG is carried out through bone defects.
It is not necessary to prepare a child for examination. The procedure is carried out without anesthesia and sedatives.
NSG allows you to set signs of increased intracranial pressure. An increase in the size of the ventricles of the brain indicates the accumulation of cerebrospinal fluid in them and the development of hydrocephalus. The detected ischemic focus indicates probable oxygen starvation. Detection of hemorrhage is an indication for urgent hospitalization.
Various cysts can be found in the research process. Subependymal cysts resemble fluid-filled cavities, located near the ventricles of the brain. Such formations require treatment. Appear due to lack of oxygen or hemorrhage.
Vascular cysts are like small bubbles with liquid, are in the place of discharge of the cerebrospinal fluid. Formed during childbirth or in the prenatal period. Usually do not require treatment.
Arachnoid cysts result from infections, hemorrhages, and injuries; they can be located in any part of the head. Their rapid growth leads to squeezing of nearby tissues. Treatment is required.
The signs of some diseases diagnosed in infancy can be detected even in the perinatal period. During pregnancy, 3 ultrasound examinations are performed, each of which reveals signs of brain pathology.
Screening for the first trimester is conducted at 12-14 weeks. It allows to detect acrania, anencephaly, exencephaly, cranial hernia, as well as signs of certain chromosomal abnormalities, for example, Down syndrome.
With acrania, there are no bones of the skull. Anencephaly is characterized by the absence of not only the bones of the skull, but also the brain. There is no bone tissue in the case of exencephaly, but the brain tissue is partially present. Cerebral hernia is diagnosed with protrusion through fragments of the dura mater through bone defects.
When screening the second trimester check the features of the formation of the brain and face. By this time all the anatomical structures and organs were formed. Great attention is paid to the head circumference and its shape, calculated as the ratio of biparietal and fronto-occipital sizes. Lemon-shaped, strawberry-shaped. Look at the size of the head – small or disproportionately large. The lateral ventricles are measured. Their increase indicates hydrocephalus.
Of particular importance is the study of the cerebellum – determine the size of the hemispheres and the degree of development of the cerebellar worm. His underdevelopment leads to inability to keep balance, muscle inconsistency, sharpness of movements, trembling of limbs. They study the visual mounds, the corpus callosum, the horns of the lateral ventricles, and many other areas of the brain.
Attention is paid to the facial skeleton. Often the shape of the nose, cleft lips are a symptom of chromosomal diseases.
The purpose of the third screening is to confirm or eliminate the defects found in the first two studies. At the same time, CTG is carried out – registration and analysis of the fetal heart rate. This study shows signs of oxygen starvation, which can have a negative impact on brain development.
How to prepare for ultrasound of the brain
Ultrasound of brain vessels is usually prescribed by a neuropathologist or therapist. Upon receipt of the referral, it is necessary to discuss the reception of vasoconstrictor or vasodilator drugs with a specialist. Probably, the doctor will ask to temporarily stop taking them.
The day before the procedure, it is recommended to exclude from the diet foods that can affect the tone of the walls: alcohol, pickles, caffeinated beverages and foods, including coffee, tea, chocolate, energy. Drinks with ginger and ginseng are also contraindicated.
Last time you need to eat for 4-5 hours before the survey. Two hours before the ultrasound is not recommended to take a hot bath. Also, do not need to smoke – smoked cigarette leads to a narrowing of the arteries and veins.
Immediately before the procedure, you should remove all the jewelry from the head and neck, and fix the hair in the tail. For examination of the cervical region it will need to be released from the clothes.
The survey is conducted in a special room. The patient is placed on a couch so that the head is located next to the ultrasound machine. A gel or a special ointment is applied to the location of the sensor to improve skin contact. Ultrasonic waves pass through a blood vessel and are reflected differently from it. The difference in the reflection depends on the speed and volume of blood flow. The reflected waves are converted into electrical impulses and transmitted to the monitor screen.
When conducting a conventional ultrasound diagnosis visualized the brain, its departments, vascular pattern.
Doppler scanning, both duplex and triplex, begins with the carotid arteries. In order to access the neck, the doctor asks the patient to turn his head to the other side of himself and checks the lower part of the artery. Following, moving up the neck, explores the direction and depth of the vessel, as well as the place where the artery is divided into branches. If triplex scanning of the main arteries of the head and their branches is used, the sonologist turns on the color mode. Highlighting shows areas of obstructed blood flow and impaired vascular wall structure.
Further vertebral arteries are studied. The sensor remains in the neck – the vessels are located near and between the cervical vertebrae.
For TCD of cerebral vessels, the gel is applied above the eyes, on the temples, the back of the head, the junction of the spine with the occipital bone. Through the orbit, it is possible to determine the characteristics of the blood flow in the arteries that pass through the superfrontal and ocular zones. On the temples check the direct sine, veins of Rosenthal, Galen, anterior, middle, posterior branches of the artery. With the help of a sensor placed on the back of the head, the state of the main and vertebral arteries, the direct sinus, the vein of Galen is determined.
Upon completion of the procedure, the patient removes the gel from the points of application. The time is 20-30 minutes.
Ultrasound with functional tests
For a more accurate diagnosis of blood flow using ultrasound of the brain and neck vessels with functional tests:
- Hyperventilation. The patient is asked to breathe several times. At this time, what is happening with the vessels and the bloodstream is observed.
- Finger pressing. The sample is aimed at the study of the roundabout path of blood flow.
- Nitroglycerine. This drug has vasodilating properties. The patient is given it under the tongue and is monitored for changes in blood flow velocity.
- Change in body position.
Features of the children
Children under one year old conduct neurosonography. The indications for ultrasound in children, including brain Doppler, are speech delay, restlessness, behavioral problems, fatigue, decreased attention, memory impairment.
In general, the preparation and sequence of actions for the procedure itself is the same as in adults. However, if adults are asked not to eat adults 4-5 hours before the procedure, then babies and children of preschool age should be fed an hour before the examination. It’s okay if babies sleep during the procedure.
Another difference is the difficulty to keep children, especially younger ones, in place, so during the study you must be prepared to calm them down. It may be enough to follow the picture that appears on the monitor. In some cases it is better to take a toy or a book with you.
Usually a few minutes after the completion of the examination, the diagnostician issues a statement and a snapshot to the patient’s hands. In decoding, the obtained figures are compared with normal ones. The results of brain ultrasound describe:
- The structure and size of the ventricles of the brain.
- The distance between the pools filled with liquor.
- The state of the walls of blood vessels, their pathological changes, features of blood flow in different phases of the contraction of the heart, resistance index and pulsation.
Doppler vein provides descriptive information about their shape, structure, patency, diameter, formations in the lumen, the rate of outflow of blood. Digital values are practically not used. The results of USDG of arterial vessels, in contrast, are presented in the form of digital analysis and comparison with normal values.
Indicators that are oriented when deciphering the results of ultrasound: no signs of deformation, compression of blood vessels, turbulence at the branch of small arteries. Arteries and veins should have sufficient clearance for the movement of blood, vertebral arteries have the same structure. Normal wall thickness is 0.9-1 mm.
Based on the characteristics obtained during the procedure, they may describe suspicions of such pathologies as:
- Stenosis is a narrowing of the vascular walls with restricted passage of blood through them.
- Atherosclerosis – cholesterol plaques appear on the walls, thickening of the vascular tissue is characteristic, echogenicity is changed.
- Aneurysm – protrusion of the vessel wall due to thinning.
- Turbulent flow – the formation of turbulence along the bloodstream.
- Occlusion – vascular obstruction.
- Vasculitis – the vascular wall is thickened, markedly impaired differentiation of its layers, echogenicity is changed.
- Arteriovenous malformation – the vascular wall between the channel of the artery and vein.
For ultrasound, there are no contraindications, it is safe and can be performed several times in a row. Restriction – damage, wounds, exacerbation of dermatitis, psoriasis, eczema. They make it impossible to apply the gel to the scalp and attach the sensor.
Difficulties may arise if the vessel is closed with bone tissue or is under a thick layer of subcutaneous fat. Difficult to study in patients with cardiac abnormalities, in particular, arrhythmia and slow blood flow.
Ultrasound diagnosis of the brain is an accurate, safe way to obtain information about the status of this organ, its divisions and blood vessels. He is appointed in case of suspicion of various pathologies associated with changes in the vascular pattern, the appearance of plaques, tumors, impaired blood flow, before preparation for operations and in the postoperative period. Usually, according to the results of this study, the doctor may prescribe a drug therapy and speed up recovery.