Doppler ultrasound - what is it in simple words?
What is it - Doppler ultrasound? Today, ultrasound diagnostic methods are becoming increasingly common in practical medicine. This popularity is due to the high degree of information content of this type of research. It also attracts physicians and the absolute safety of the procedure carried out for the organism of both a healthy person and a pregnant woman. There are quite a few options for ultrasound, developed for each individual system and structure of our body, which are available to the sensor apparatus.
Where does it apply?
Most of all, however, the use of ultrasound is characteristic of the pediatric and obstetric areas. This is due to the fact that only proven and safe research methods should be used in these areas. Reflected from internal structures, radiation from ultrasound does not harm the patient. Doplerometry or USDG are also based on these operating principles.It allows you to evaluate graphically the direction and speed of blood flow in the vessels. This method is used during pregnancy to check the blood circulation of the mother, fetus and placenta. What is it - Doppler ultrasound, it is interesting to many.
Some women, having received a referral to this type of research, are frightened, because doctors do not give explanations about how the Doppler ultrasound is performed and what is its essence. The reality is that the Doppler ultrasound is no different from conventional ultrasound in terms of the procedure itself. The main difference in the parameters to which the doctor draws attention during the study.
Before considering the varieties of Doppler ultrasound, it makes sense to understand the principles of its operation. The basis of doplerometry is radiation from ultrasound, but it differs from conventional ultrasound in how the reverse signal is perceived. This phenomenon in physics is called the Doppler effect, which gave the name to the technique. The mechanisms of action of ultrasound Doppler vessels and its difference from conventional ultrasound are as follows:
1. Standard ultrasound generates wave radiation with equal intervals of time and, according to the same principle, perceives its reflection.With its help, it is convenient to investigate relatively stationary organs and structures that remain virtually unchanged with time. Ultrasound doppler neck is now very widespread.
2. It will not be possible to investigate the blood flow in this way, since it is intrinsic to the blood that is constantly in motion in the cavity of the vessel. As a result, the usual ultrasonic emitter is not able to fix the speed of blood flow.
3. The principle of operation of the doplerometer is similar to radar. It is able to record and record separately taken oscillations, making measurements of indicators by means of reflected radiation.
4. The Doppler transducer, thus, directs ultrasound waves at a certain speed, and takes back with another. Evaluation of such data became the basis of the methodology. That is, the quality of the blood circulation of the vessel depends on how fast the ultrasound wave returns.
The first study based on Doppler ultrasound (what we are, we explained) was spectral flux doplerometry. It gives an estimate of the indicators in the M-echo mode. The results obtained were verified by means of a diagram that changed in the presence of pathology.In the future, the study was supplemented by visualization and was called "Doppler echocardiography" and "color mapping". These techniques are used to identify developmental pathologies in the fetus.
This method is unique and indispensable. This is the only study that provides an opportunity to assess the state of the blood flow of the uterus, placenta and fetus during pregnancy. It should be borne in mind that Doppler is carried out only if there are certain indications. In other cases, the usual three screenings in the amount of three pieces.
If there are complications during pregnancy, the appointment of an Doppler ultrasound can be done from the 20th week onwards. However, the vast majority of research is conducted after the 30th week. This is the period of the planned ultrasound, and it is convenient to combine it with the ultrasound Doppler of the vessels.
Not only the speed of blood movement through the vessels of the uterus and placenta is checked, but also individual fetal arteries, including the umbilical cord. Such a thorough study is due to the fact that the speed of blood flow is quite rarely broken at the same time in several vessels.
All indicators are recorded in the M-echo mode. The screen displays a diagram showing the oscillations of the back radiation. Three-dimensional image of this type of research does not, only the waves that correspond to the movement of blood in the arteries. In addition to this, a sound image of vibrations is also obtained. It enables the sound specialist to identify a change that is invisible in the diagram. Ultrasound with Doppler vessels of the neck is very informative.
The heart is the basis of the circulatory system, so checking its work is also an integral part of the diagnosis. The widespread use of echocardiographic techniques made it possible to use them during pregnancy to assess the state of the heart in a child. However, at the initial stage there were no sensors capable of detecting changes in such a tiny organ.
What features does he have?
Modern devices, in particular, Doppler, are equipped with a three-dimensional image firing mode. The combination of echocardiography with Doppler allowed to improve both methods, which made the following possible:
1.Such visualization makes it possible not only to assess the direction and speed of blood movement in the vessels, but also to check their structure and position. Thus, the modern method supplanted the previous ones and became the leading and most common. Ultrasound Doppler of the lower extremities is required for thrombosis.
2. The study of vessels has ceased to be superficial. Now not only blood flow in the aorta, the umbilical cord and the middle cerebral artery is studied. A high degree of visualization allows you to see the vessels in individual organs of the fetus.
3. The final stage of the study becomes a heart test. The dimensions of the organ cavities, the state of its individual structures are measured. It has become possible in the early stages to diagnose heart defects.
Although this technique is highly informative, not every specialist diagnostician can do it. In addition, it is quite expensive. Nevertheless, anyone can do an ultrasound with a Doppler.
This is a new version of the study, which allows you to correctly and thoroughly check the venous and arterial blood flow in different modes. This study makes it possible to describe several indicators of the circulatory system simultaneously.It can be both the external structure of the vessel, and indicators of individual blood flow. Thus, it turns out not only to assess the speed of blood flow, but also to exclude its incorrect movement.
The study has several features:
1. Mapping in the color version makes it possible to record the direction of blood flow in the vessels, digitize the obtained indicators and create a three-dimensional picture simultaneously. Carry out an ultrasound of the kidneys with Doppler.
2. The speed and direction of the vessels are indicated on the screen in different colors. This provides the possibility of simultaneous examination of the venous and arterial vessels.
3. The study is applied in structures where several vessels are closely spaced. This is what makes it convenient for checking blood flow in the veins and arteries of the fetus and placenta.
In the normal course of pregnancy, the doppler of the vessels of the placenta, fetus and uterus is not prescribed. In this case, regular scheduled ultrasound examinations are sufficient. Doppler may be needed in a situation where there is a potential or pronounced risk of complications during pregnancy.Indications for Doppler ultrasound can be a variety of diseases not only for a pregnant woman, but also for a child:
Multiple pregnancy. Doppler is prescribed to avoid twisting or compressing the umbilical cord when twins are moving in the uterus. In this case, even in the normal course of pregnancy, the doctor will prescribe a Doppler study.
Diabetes and other endocrine diseases, pathologies of the urinary and cardiovascular systems, arterial hypertension and other somatic illnesses.
Preeclampsia during pregnancy. Eclampsia is considered to be the critical state of a woman, in which spontaneous miscarriage and fetal death is possible.
Changes in the membranes of the fetus, revealed by ultrasound. Also lack of water or polyhydramnios, pathologies in the structure and position of the umbilical cord, early maturation of the placenta.
Delay in fetal development.
Incompatibility of the Rh factors of the child and the mother. This is especially true of re-pregnancy.
Preparation for the study
When a woman is prescribed Doppler ultrasound, she is asked to prepare for this type of research.It should be understood that the Doppler is just a kind of ultrasound, therefore, no specific preparation will be required for it.
The most standard recommendations on this are:
1. Most often, disposable sheets and napkins are used in hospitals, but you can take a clean cloth with you just in case.
2. After the procedure, you will also need several paper napkins to erase the gel.
3. You can not eat tight and drink a lot before the procedure. This is due to the fact that pressing the sensor can cause discomfort in the stomach.
4. Clothing should be loose so that it is easy to take off before the procedure.
The duration of the procedure depends on the diagnostic option and is up to 30 minutes.
According to the external characteristics of the study with the Doppler does not actually differ from the standard ultrasound. Most often they are performed on the same device with switching modes and using different sensors. The main difference is the very essence of the procedure. The study is conducted as follows:
1. The primordial position of a woman is horizontal on the back.Closer to childbirth, a woman is recommended to turn slightly to the left to relieve tension from the uterus.
2. A specialist using a special sensor identifies the arteries of the uterus and their branches, as well as umbilical cord vessels. Next is a description of the quality of blood flow in the uterus and placenta.
3. Calculations are made on the basis of comparison and the ratio of blood flow in each heart rhythm.
4. For each group of vessels, several indicators are calculated. They are the pulsation index, blood flow rate, systolodiastolic ratio and resistance index.
5. The obtained indicators are compared with the norm, then a conclusion is made. What is the rate of Doppler ultrasound?
To determine the further strategy of monitoring and management of patients with deviations in doplerometry, the division into three severity of blood flow disorders is used. It should be borne in mind that entering into one of the categories occurs regardless of the numbers received, since the localization of the detected deviations is important.
1. Degree 1A. Blood flow rate is reduced only in the placenta and uterus.At the same time, the vessels that bind the fetus and the placenta are unchanged and there are no signs of abnormalities in the fetal development of the child. Decoding ultrasound with Doppler should be carried out only by a highly qualified specialist.
2. Degree 1B. With it, the blood flow between the uterus and the placenta is not disturbed, while in the placental-fetal there is a decrease in performance. In this case, there are first signs of intrauterine growth retardation.
3. The second degree is characterized by impaired blood flow in both directions, that is, both between the uterine and placental, and between the vessels of the fetus. However, it is still possible to preserve the life of the fetus.
4. The third degree is a sign of critical and irreversible changes in the bloodstream. This condition can lead to death of the fetus.
The first degrees suggest enhanced control over the condition of the pregnant woman. If a third degree of severity of blood flow disorders was initially detected, this is a signal for emergency delivery.
Where do dozler ultrasound?
You can perform this procedure in a large medical diagnostic center.For example, in Moscow you can sign up at the Alexandra Med center, visit the On He Clinic international center. The cost of the study - from 1800 rubles.
We considered what it is Doppler ultrasound.