Midbrain, cerebral aqueduct, evolution of the midbrain. How to make sense of all these numbers. Middle cerebral artery

During pregnancy, especially in the last trimester, doctors can refer the expectant mother to such a study as dopplerometry.

Dopplerometry of the fetus is a subspecies of ultrasound diagnostics that allows you to evaluate the characteristics of blood flow in the vessels of the child, uterus and placenta. Based on the results of the study, it is possible to judge whether the baby is suffering from a lack of oxygen (hypoxia) and, in the case of a positive answer, to establish exactly where the blood flow disturbance occurred: in the uterus, placenta or umbilical cord.

Oxygen is the most important element, with the participation of which the metabolism in the cell occurs properly. If there is not enough oxygen, then the energy necessary for the growth and functioning of tissues is not enough. As a result, hypoxia is a reason for intensive treatment in stationary conditions.

The method is based on the so-called Doppler effect - the property of an ultrasonic wave to be reflected from moving bodies and change the frequency of its oscillations. In our case, this is a change in the frequency of the reflected ultrasonic signal from an unevenly moving medium - blood in the vessels. Changes in the frequency of the reflected signal are recorded in the form of curves of blood flow velocities (BFR). The first attempt to use dopplerometry in obstetrics was made in 1977 to assess blood flow in the umbilical artery. In subsequent years, the widespread use of dopplerometry made it possible to significantly reduce the percentage of such serious complications as severe forms preeclampsia, fetoplacental insufficiency, delayed prenatal development and intrauterine fetal death. The frequency of complications during childbirth (distress syndrome, fetal asphyxia) has decreased.

There are two types of dopplerometry:

• duplex

  The wave is not sent constantly, but in cycles. As a result, the sensor captures the reflected ultrasound, sends it for processing, and at the same time “gives out” a new “portion” of signals. The result image is displayed in black and white.

• Triplex

  It is based on the same method, only the blood flow velocity in different parts of the vessels is encoded different color. These shades are superimposed on a two-dimensional image. The bloodstream will be colored red and blue. The color does not depend on the type of vessel (vein or artery), but on the direction of blood flow - from the ultrasound sensor or towards it. A color picture gives a clearer image and allows you to see what is unrealistic to see in a two-color image.

According to the sensations for the patient, the procedure does not differ from the standard ultrasound. To prepare for a Doppler study, a pregnant woman does not need to do anything, however, it is advisable not to eat for a couple of hours before visiting the ultrasound room, but to limit yourself to water. A special conductive gel is applied to the surface of the pregnant woman's abdomen, which helps the penetration of the ultrasonic signal, and an ultrasonic sensor is installed, which is smoothly driven over the surface of the abdomen.

The method allows you to determine the diameter and location of the main arteries not only of the fetus, but also of the placenta, umbilical cord, uterus, the speed of blood flow through the vessels. Dopplerometry also helps to identify abnormalities in the functions of the placenta, which can lead to complications during pregnancy and during childbirth.

Dopplerometry is becoming more and more widespread, as it allows using a non-invasive (atraumatic and bloodless) procedure to determine the condition of a pregnant woman and child. Diagnosis does not harm either the mother or the unborn baby. Exposure to ultrasound is of a short duration and exactly complies with safety standards in terms of power and thermal index. Therefore, the heating from ultrasonic waves is not significant and does not affect the embryo.

Indications for dopplerometry

According to the order 572-n of the Ministry of Health of the Russian Federation "On approval of the Procedure for the provision of medical care in the profile" obstetrics and gynecology (excluding the use of assisted reproductive technologies) "" in the third trimester, each expectant mother will have to undergo a screening ultrasound of the fetus for a period of 30-34 weeks with dopplerometry .

However, fetal dopplerometry can be prescribed repeatedly as a planned procedure for the following indications:

• Pregnancy disease:
  - preeclampsia;
  - hypertonic disease;
  - kidney disease;
  - collagen vascular diseases;
  - diabetes;
  - Rh sensitization.
• Diseases and congenital malformations of the fetus
  - IUGR (intrauterine growth retardation);
  - discrepancy between the size of the fetus and the gestational age;
  - unexplained oligohydramnios;
  - premature ripening placenta;
  - non-immune dropsy of the fetus;
  - dissociated type of fetal development in multiple pregnancy (a situation where one fetus in the womb develops in accordance with age and duration, and the second is significantly behind);
  - birth defects hearts;
  - other fetal malformations;
• Other factors
  - pathological types cardiotocogram
  Cardiotocography (CTG) - registration of the heart rate (HR) of the fetus and uterine tone with a graphical representation of the signals. Registration of heart rate is performed by an ultrasonic sensor based on the Doppler effect already described by us;
  Cardiac activity most accurately characterizes the functional state of the fetus, therefore, CTG is timely diagnosis various kinds of violations. CTG allows you to choose the tactics of therapeutic measures, as well as optimal time and method of delivery.
  - fetal distress and stillbirth in previous pregnancies
  - maternal age over 35 or under 20 (early or late pregnancy)
  - prolongation of pregnancy;
  - entanglement of the neck of the fetus with the umbilical cord;
  - Injury to the abdomen of a woman.

Doppler Principles and Measurement Indices

Dopplerometry is possible not earlier than the 20th week of pregnancy, that is, after the final formation of the placenta, and it is most informative during the period of intensive fetal growth, which occurs from the 27th to the 34th week of pregnancy.

The most accessible and convenient vessels for research are the fetal umbilical cord arteries and uterine arteries. The study of the uterine arteries allows you to assess the state of the vascular system of the uterus, placenta, intervillous space. Blood circulation in the uterus of a woman is carried out with the participation of the ovarian and uterine arteries. Even during the formation of the placenta, changes occur in the walls of these arteries, which subsequently lead to their growth and expansion in parallel with the growth of the placenta. Due to this, the uteroplacental blood flow is formed to the full formation of the placenta and increases 10 times. When complications arise during pregnancy, some arteries do not dilate and grow during the growth of the placenta. Thus, they become unable to provide a sufficient degree of blood circulation and blood supply to the placenta, which can lead to a violation of its function, which entails a deficiency nutrients and oxygen in the fetus. This can lead to placental abruption, premature birth or death of the fetus.

AT special occasions blood flow can also be measured in other vessels: the aorta or the baby's middle cerebral artery. The most informative study of the middle cerebral artery. The study of the vessel is possible only with the use of color Doppler mapping (CDM), which allows you to clearly visualize the vessels of the circle of Willis. This analysis is more sensitive to the risks of adverse perinatal outcome than similar measures of blood flow in the umbilical artery. Blood flow disorders in the aorta are detected, as a rule, only from 22-24 weeks.

Indications for these types of studies may be:

• Rh conflict in the case of an Rh-positive fetus and an Rh-negative mother
  The penetration of fetal (fetal) Rh-positive erythrocytes into the mother's bloodstream causes her immune response with the production of antibodies that freely enter the fetal bloodstream through the placenta and cause the destruction of its blood cells. The child develops severe anemia, which triggers the development of a severe form of hemolytic disease up to the death of the fetus.
• suspected intrauterine growth retardation (IUGR)
• non-immune dropsy of the fetus,
• congenital malformations of the fetus,
• anomalies of the vessels of the umbilical cord,
• pathological types of cardiotocograms

Dimension indexes

Doppler ultrasound results are evaluated by an obstetrician who observes the woman's pregnancy. This is done based on several indicators:

• resistive index, or resistance index (RI): the ratio of the difference between the systolic and minimum (diastolic) blood flow velocities and its maximum value
• pulsation index (PI): the ratio of the difference between the maximum and diastolic blood flow velocities in this vessel to the average value of the velocity, the ratio of the velocity of blood flow through the vessel in systole and diastole
• Systolodiastolic ratio S/D, where
  C - maximum systolic blood flow velocity;
  D - end diastolic blood flow velocity;
  avg. - average blood flow velocity (calculated automatically).
  LMS and IR essentially characterize the same thing.

High index values ​​characterize increased resistance to blood flow, low values reflect a decrease in resistance to blood flow. If the indices do not correspond to the norm, this may indicate the development of pathology of the placenta and a violation of the condition of the fetus.

Degrees of blood flow disturbance and indications for additional dopplerometry

The results of dopplerometry, analyzed by an experienced specialist, allow you to find out important information about the state of health of the fetus and give a prognosis regarding the further course of pregnancy. Do not forget that you need to interpret the data taking into account the rest of the analyzes of the pregnant woman and her medical history.

Deviations from the norm are observed with impaired intrauterine circulation, which has three degrees:

1 degree:

A - violation of the uteroplacental blood flow with preserved fetal-placental blood flow (increased IR in the uterine artery, and in the umbilical artery is normal);

B - violation of the fetal-placental blood flow with preserved utero-placental blood flow (increased IR in the umbilical artery, and in the uterine arteries is normal;

2 degree : simultaneous violation of the uteroplacental and fetal-placental blood flow (impaired blood flow in both the uterine arteries and the umbilical cord), not reaching critical changes (end diastolic blood flow is preserved);

3 degree : critical disorders of fetal-placental blood flow (lack of blood flow or reverse diastolic blood flow) with preserved or impaired uteroplacental blood flow.

Dopplerometry is prescribed more often than once or twice if there are risks of fetal developmental pathology or pregnancy complications, and also if the condition of the uterus and placenta requires it. If a blood flow disorder is detected, after appropriate treatment, a control Doppler examination is prescribed to assess the effectiveness of the therapy in 7-14 days.

With 1 degree of violations, if there is a suspicion of a deterioration in the condition of the fetus, dopplerometry is performed again after 2-3 weeks, in the gestation period after 32 weeks, it is imperative to conduct repeated monitoring of CTG.

At grade 2, hospitalization is required. Doppler control is necessary every 3-4 days, CTG every 2-3 days, sometimes daily.

At grade 3, the question is raised about conducting an emergency delivery by caesarean section. With a very premature pregnancy and an unfavorable prognosis for the fetus, a council is assembled and a decision is made on further management tactics, taking into account the desire of the woman.

Doppler norms by week

For each period of pregnancy, certain normative values ​​of blood flow indices correspond. If the values ​​obtained correspond to them, then the blood flow is normal.

Do not despair if the study revealed some deviations. The results obtained will allow the doctor to correct the further course of pregnancy and prevent possible problems.

The norms of dopplerometry during pregnancy are presented in the table:

Every expectant mother should know that normal Doppler measurements during pregnancy are an important indicator for assessing the course of pregnancy. The blood circulation of the fetus requires careful monitoring, because the health and happy future of your baby depends on it!

Doppler utero-placental-fetal blood flow

INTRODUCTION

The Doppler effect is based on the change in the frequency of a sound wave depending on the speed of the observed emitter. In our case, it is a change in the frequency of the reflected ultrasonic signal from an unevenly moving medium - blood in the vessels. Changes in the frequency of the reflected signal are recorded in the form of curves of blood flow velocities (BFR).

Hemodynamic disturbances in the functional system "mother-placenta-fetus" are the leading pathogenetic mechanism of violation of the state and development of the fetus in various complications of pregnancy. At the same time, in the vast majority of observations, hemodynamic disorders are characterized by the universality and uniformity of changes, regardless of the state of the fetus and the etiopathogenetic factor.

A change in the normal parameters of CSC is a non-specific manifestation of many pathological conditions of the fetus, and in many cases preceding the appearance of clinical symptoms, it is important that this also applies to the main pathological conditions during pregnancy - FGR, fetal hypoxia, preeclampsia, etc. With a period of 18-19 to 25-26 weeks Doppler is the method of choice, because the biophysical profile of the fetus is informative from 26 weeks, and cardiotocography is not yet indicative.

The Doppler technique involves obtaining curves of blood flow velocities in the vessels of the utero-placental-fetal blood flow, calculation of vascular resistance indices (VR), and analysis of the results obtained.

INDICATIONS FOR DOPPLEROMETRY

V.V. Mitkov (1)

1. Disease of a pregnant woman:

Hypertonic disease;

kidney disease;

Collagen vascular diseases;

Rh sensitization.

2. Diseases and congenital malformations of the fetus

Mismatch between the size of the fetus and the gestational age;

Unexplained oligohydramnios;

Premature maturation of the placenta;

Non-immune dropsy;

Dissociated type of fetal development in multiple pregnancies;

Congenital heart defects;

Pathological types of cardiotocograms;

umbilical cord anomalies;

Chromosomal pathology.

3. Complicated obstetric history (FGR, gestosis, fetal distress and stillbirth in previous pregnancies).

INDICES OF VASCULAR RESISTANCE (VR)

To assess the curves of blood flow velocities (BSCs), the indices of vascular resistance are proposed:

2. Pulsation index (PI, Gosling R., 1975),

(S-D)/avg.

3. Systodiastolic ratio (LMS, Stuart B., 1980),

C - maximum systolic blood flow velocity;

D - end diastolic blood flow velocity;

avg. - average blood flow velocity (calculated automatically)

LMS and IR are essentially the same thing.

In the formula for calculating PI, the average value of the blood flow velocity is used, which makes it possible to more accurately assess the shape of the blood flow curve and quantitatively analyze the CSC at zero diastolic blood flow, when LMS and IR lose their mathematical meaning. However, given that in this case (for choosing the tactics of managing pregnancy and childbirth), it is important in itself to have a qualitative change, rather than quantitative nuances, and that most of the printed research papers on doplerometry in obstetrics were carried out with the calculation of LMS, then in this moment in practical work it is more expedient to use LMS.

A.N. Strizhakov and co-authors proposed a placental coefficient (PC), which allows to simultaneously take into account changes in both uteroplacental and fetal-placental blood flow, reveals a minimal deviation from the normative values ​​of blood circulation parameters in the “mother-placenta-fetus” functional system.

PC=1/(LMS ma + LMS up)

PC - placental coefficient;

SDO ma, SDO ap - systole-diastolic relations in the uterine artery and umbilical artery.

CLASSIFICATION OF BLOOD CIRCULATION

V.V. Mitkov (1).

1st degree:

A - violation of uteroplacental blood flow with preserved fetal-placental blood flow;

B - violation of the fetal-placental blood flow with preserved utero-placental blood flow;

Grade 2: simultaneous violation of uteroplacental and fetal-placental blood flow, not reaching critical changes (end diastolic blood flow is preserved).

Grade 3: Critical disorders of fetal-placental blood flow (lack of blood flow or reverse diastolic blood flow) with preserved or impaired uteroplacental blood flow.

During dynamic observation, there is no normalization or improvement in hemodynamic parameters with 1A, 2 and 3 degrees of impaired uteroplacental-fetal blood flow. Normalization of fetal-placental blood flow was noted only at grade 1B, usually in pregnant women with the threat of interruption.

CLASSIFICATION OF FETUS HEMODYNAMIC DISTURBANCES

A.N. Strizhakov et al. (2).

1st DEGREE - a violation of the fetal-placental blood flow, not reaching critical values ​​​​and a satisfactory state of the fetal hemodynamics (impaired blood flow only in the umbilical artery). LMS in the thoracic aorta - 5.52 ± 0.14, in the internal carotid artery - 3.50 ± 1.3. There is a compensatory decrease in the diastolic function index of both ventricles of the fetal heart in 58.3% of cases, an increase in the maximum blood flow velocity through all heart valves in 33.3%.

2 DEGREE - compensated violation of the hemodynamics of the fetus (violation of the actual hemodynamics of the fetus). Centralization of the fetal circulation. Reducing the maximum blood flow velocity through all valves of the fetal heart in 50% of cases, for the left sections - to a lesser extent. Further decrease in diastolic ventricular function (E/A). Prevalence of the right parts of the fetal heart remains. Pathological spectrum of blood flow in the aorta and / or internal carotid artery of the fetus. Aorta - a violation of blood circulation by the type of violations in the artery of the umbilical cord. In the internal carotid artery, an increase in the level of diastolic blood flow is a decrease in the resistance of the microvascular bed of the fetal cerebral hemispheres. In 100% of cases, circulatory disorders in these vessels are secondary to changes in the umbilical artery. The secondary nature of changes in the internal carotid artery to changes in the fetal aorta has not been established. The primary change in the blood circulation of the cerebral vessels is much less common (non-placental type of fetal hypoxia).

2 degree is not long, quickly passes into 3 degree.

3 DEGREE - a critical state of fetal hemodynamics.

The functional predominance of the left parts of the heart over the right ones is a deeper restructuring of intracardiac hemodynamics associated with the centralization of blood circulation. Increased fetal hypoxia - a decrease in transvalvular blood flow by 10.3% for the valves of the left sections and by 23.3% for the right ones. Functional insufficiency of the tricuspid valve in 66.7% of cases (flows of regurgitation). Aorta - decrease in diastolic blood flow to its absence (69.6%). Decreased resistance of the internal carotid artery in 57.1% of cases. The combination of simultaneous violations in the aorta and in the internal carotid artery more often than in the 2nd degree of violation (14.3% and 42.3%, respectively).

Stages of violations.

1 degree goes to the second after an average of 3 weeks; 2 to 3 in 1.3 weeks. It is possible to compensate for violations in various stages, more in the first stage, less in the second. In stage 3 - decompensation of fetal hemodynamics.

Perinatal losses: 1st degree of fetal hemodynamic disorders - 6.1% of cases, 2nd degree - 26.7%, 3rd degree - 39.3%.

Intensive care of newborns: 1st degree - 35.5%, 2nd degree - 45.5%, 3rd degree - 88.2%.

DOPPLEROMETRY OF THE UMBILICAL ARTERY

(normative indicators)

Registration of CSC in the umbilical artery after 18 weeks is possible in 100% of cases.

V.S. Demidov (3).

Up to 22 weeks, the determination of blood flow in the umbilical artery is not informative, since there is no normal diastolic component (a sign of placental insufficiency). A.N. Strizhakov recommends starting the study at 16 weeks.

PI decreases with increasing gestational age:

10-11 weeks - 1.92±0.47 (no diastolic component);

29-30 weeks - 1.15±0.21.

A.N. Strizhakov (12).

The threshold value of LMS during pregnancy 28-40 weeks is 3.0.

S. Gudmundsson (6).

In North America, it is proposed to use the numerical value of LMS - 3.0 as the upper limit of normal until late pregnancy.

Nomograms of the systole-diastolic ratio (S/D) during the second half of pregnancy.

V.V. Mitkov (1).

Normative indicators of the DM ratio for the umbilical arteries in the second half of pregnancy.

Normative parameters of PI of the umbilical cord arteries in the second half of pregnancy.

S.A. Kalashnikov (7).

Umbilical artery in the third trimester of pregnancy: the average blood flow velocity is 32-39 cm/sec; PI - 0.64-0.89.

L.V. Logvinenko (5).

The values ​​of blood flow indicators in the umbilical artery in the 3rd trimester of pregnancy:

SDO - 2.6±0.7; IR - 0.62±0.19.

DOPPLEROMETRY OF UTERINE ARTERIES

(normative indicators)

Registration of CSC in the uterine artery may present some technical difficulties when using black and white Doppler, since the uterine artery is not visualized and is determined "by touch" by the characteristic appearance of the CSC. The study time can take up to 30-60 minutes. When using an ultrasonic device with color Doppler mapping of the "Acuson" type, the examination time is reduced to 5-7 minutes.

M.V. Medvedev (9).

Registration of CSC in the uterine arteries is possible: in the left in 99% of cases; in the right - in 97%. Difficulties in determining occur in the first trimester of pregnancy. Indices of vascular resistance (VR) - averaged data of five cardiocycles. In the first trimester, high ISS, in the 2-3 trimesters of uncomplicated pregnancy - a high diastolic component (low peripheral resistance).

In the 2nd half of pregnancy, the numerical values ​​of the ASC of the uterine artery are stable, slightly decreasing towards the end of pregnancy.

Pathological SDO CSC in the third trimester of pregnancy - more than 2.4-2.6.

ASCs in different uterine arteries are significantly different in the third trimester of pregnancy with a lateral location of the placenta. ISS from the placenta is lower by 12-30%.

Pathological CSCs: decrease in the diastolic component of blood flow, dicrotic notch in the early diastole phase.

V.V. Mitkov (1).

Dicrotic recess - deeper violations. It is recorded when its peak reaches or is below the end diastolic velocity level.

Violation of blood flow more often in one artery (more than 70% of cases), i.e. Both arteries must be examined.

B.E. Rosenfeld (10)

IR average - 0.482+0.052.

After 29 weeks, the threshold value of LMS (at least on one side) is 2.4, IR is 0.583.

V.V. Mitkov (1).

Normative indices of IR of uterine arteries in the second half of pregnancy.

Normative indicators of PI of the uterine arteries in the second half of pregnancy.

L.V. Logvinenko (5).

Arcuate arteries of the uterus in the third trimester of pregnancy.

ISS: LMS - 2.5± 1.2; IR - 0.6 ± 0.3.

S.A. Kalashnikov (7).

Third trimester of pregnancy. Average speed - 60-72 cm/sec, PI - 0.41-0.65.

A.N. Strizhakov (12).

The threshold value of LMS during pregnancy 28-40 weeks is 2.4.

DOPPLEROMETRY OF FETUS VESSELS

(normative indicators)

V.V. Mitkov (1).

Possibility of registration:

16-19 weeks - in 50% of cases;

20-22 weeks - in 96%;

23 weeks - in 100%, 36-41 weeks - in 86%.

In the first half of pregnancy, the ASC does not change significantly.

The mean blood flow velocity increases from 20 cm/sec at 20 weeks to 30 cm/sec at 40 weeks.

Of practical interest in the study of CSC is after 22-24 weeks, because. early violations, as a rule, are not detected due to the large compensatory possibilities of fetal hemodynamics.

Cerebral vessels of the fetus.

The most informative study of the middle cerebral artery. The study of the vessel is possible only with the use of color Doppler mapping (CDM), which allows you to clearly visualize the vessels of the velius circle. CSC in the cerebral arteries have the form characteristic of the vascular system of medium resistance - without negative values ​​of diastolic blood flow.

With CDC registration of the middle cerebral artery in 95% of cases.

Blood flow velocity increases from an average of 6 cm/sec at 20 weeks to 25 cm/sec at 40 weeks.

ISS in the middle cerebral artery increase from 20 to 28-30 weeks, and then decrease.

L.V. Logvinenko (5).

Aorta: LMS - 6.0 ± 2.1; IR - 0.83±0.72.

Common carotid artery: LMS - 7.3±3.2; IR - 0.83 ± 0.17. Internal carotid artery: LMS - 4.3±1.5; IR - 0.77 ± 0.22.

V.S. Demidov (13).

Pathology of LMS in the internal carotid artery 7.0 or more (with a period of 34-38 weeks of pregnancy). The norm is 4.0-6.9.

A.N. Strizhakov et al. (eight).

Internal carotid artery:

IR 23-25 ​​weeks - 0.94±0.01;

26-38 weeks - 0.89±0.01;

29-31 weeks - 0.85AO.01;

32-34 weeks - 0.8 ± 0.01;

35-37 weeks - 0.76 + 0.09;

38-41 weeks - 0.71±0.09.

LMS less than 2.3 - pathology.

D.N. Strizhakov et al. (eleven).

The internal carotid artery is recorded at 19-41 weeks. Before 25 weeks there is no diastolic component in most cases.

Decreased IR from 0.95±0.015 at 19-22 weeks to 0.71±0.09 at 38-41 weeks.

V.V. Mitkov (1).

Normative indicators of PI of the fetal aorta in the second half of pregnancy.

Normative indicators of PI of the fetal middle cerebral artery in the second half of pregnancy.

A.N. Strizhakov et al. (12).

Pathological ISS during full-term pregnancy: fetal aorta - 8.0 and above; internal carotid artery - 2.3 and below.

B.E. Rosenfeld (10).

ASC in the middle cerebral artery at a period of 22-41 weeks.

The SDO norm is more than 4.4, IR - 0.773.

The norm does not mean a satisfactory condition of the fetus.

DOPPLEROMETRIC CHARACTERISTICS OF THE DISTURBANCE

UTERO-PLACENTAL-FETAL BLOOD FLOW

V.V. Mitkov (1).

Currently, there are no sufficient grounds and convincing data to consider the use of Dopplerography as a screening method in obstetrics justified, however, the fact that Doppler study of uteroplacental and fetal blood flow has an important diagnostic and prognostic value in the group of pregnant women with high perinatal risk.

placental insufficiency.

Not all forms of placental insufficiency are accompanied by significant changes in uteroplacental and placental-fetal blood flow. Most of the false negative results seem to be related to this. Therefore, it is necessary to emphasize the need for a comprehensive accounting of the data of the three main complementary research methods: echography, CTG and Doppler. SZRP - a typical manifestation of placental insufficiency. The primary link in the occurrence of sdfd in the second trimester of pregnancy is a violation of the uteroplacental blood flow (in 74.2% of cases, sdfd occurs). With the involvement of two arteries - in 100% of cases. In the vast majority of these cases, early delivery is required. Occurring cases of an isolated violation of the fetal-placental blood flow in sdfd is associated for the most part with a violation of the structure of the placenta.

Reasons for false positive results:

1). The severity of FGR does not always correspond to the severity of fetal hemodynamic disorders, which is explained by the different adaptive response of the fetus to approximately the same severity of delay and duration of intrauterine suffering.

2). Some newborns are born with a minimal weight deficit, their condition does not require intensive monitoring and treatment and therefore is not taken into account during the analysis, while neonatologists make a diagnosis of malnutrition, guided by the weight-growth coefficient.

intrauterine hypoxia.

Of great practical value is the use of dopplerometry to detect chronic distress, which contributes to prenatal identification of groups of newborns that are subject to careful observation and treatment. Doppler study of fetal blood flow allows diagnosing intrauterine hypoxia somewhat earlier than cardiotocography.

Evaluation of CSC in the middle cerebral artery and fetal aorta gives better results in the diagnosis of intrauterine hypoxia than with a similar assessment of the umbilical artery.

The most convincing signs of fetal hypoxia are a decrease in heart rate variability and the appearance of prolonged deep decelerations during CTG, but this is more consistent with cases of critical blood flow in the umbilical artery and fetal aorta. Therefore, in the diagnosis of hypoxia, we preferred CTG, and dopplerometry and echography have priority in identifying a group of pregnant women at high risk for perinatal pathology (pregnant women in this group are subject to dynamic comprehensive monitoring and treatment).

Pathological CSCs in the venous duct, umbilical inferior vena cava and hepatic veins have a greater prognostic value compared to arterial vessels.

Uteroplacental hemodynamics is primarily disturbed. Changes in blood flow in the umbilical artery, fetal vessels, as a rule, are secondary (in 16%, an isolated violation of fetal-placental blood flow was observed).

In the 3rd trimester of pregnancy, with unexpressed clinical symptoms of preeclampsia, recorded pathological CSCs in the uterine artery precede a significant rapid increase in severity in a few weeks.

Dopplerometry allows predicting the occurrence of preeclampsia and placental insufficiency based on the detection of pathological CSCs in the uterine artery in the 2nd trimester of pregnancy, especially at 21-26 weeks.

There is a significant correlation between the ASC in the umbilical artery and the level of glucose in the blood plasma in pregnant women with diabetes mellitus. Dopplerometry of the umbilical artery has the highest accuracy in identifying a group of high perinatal risk in this disease than PPP, CTG, which allows you to more adequately assess the condition of the fetus and choose the optimal tactics for managing pregnancy.

Rh sensitization.

In proportion to the severity of Rh sensitization, an increase in the volumetric blood flow rate in the umbilical vein occurs, reaching maximum values ​​in critical cases requiring intrauterine blood transfusions. Volumetric blood flow in the umbilical vein increases by an average of 65%, specific blood flow by 27%. An increase in blood flow is a compensatory response to a decrease in hemoglobin in the blood of the fetus. The average blood flow velocity in the aorta, inferior vena cava, IR in the umbilical artery increases.

Multiple pregnancy.

With a difference in SDO CSC in the umbilical cord artery of twin fetuses by more than 0.8 with a sensitivity of 64%, a specificity of 100%, dissociated fetal growth can be established.

Cerebral vessels of the fetus.

Violation of blood flow is characterized by an increase in the diastolic component of the CSC. An increase in cerebral blood flow is a compensatory centralization of fetal circulation during intrauterine hypoxia, characterized by a redistribution of blood with a predominant blood supply to vital organs (cerebral hemispheres, myocardium, adrenal glands) - "brain sparing effect". The presence of the effect is characteristic of the asymmetric form of fetal growth retardation.

An increase in ISS is also a pathological sign. With an increase in SDS in the internal carotid artery above 7.0, signs of intrauterine infection were noted in 38.5% of cases. In 57.7% of cases, the neonatal period was complicated by pneumonia, and more than 35% of newborns were diagnosed with various CNS pathologies.

The most accurate results are achieved in the study of CSC in the middle cerebral artery of the fetus.

fetal aorta.

The nature of the change in CSC is similar to that in the umbilical artery, but the prognostic significance is higher. With the appearance of reverse diastolic blood flow, intrauterine death occurs after 24 hours. In the case of critical values ​​of fetal-placental blood flow, perinatal outcomes depend on the parameters of blood flow in the fetal aorta. With "zero" retrograde diastolic blood flow in the fetal aorta against the background of similar values ​​of diastolic blood flow in the umbilical artery, perinatal mortality is 2 times higher (52.6 and 25%), antenatal death of the fetus is 3 times higher (90 and 33.3%) according to compared with the group with normal and pathological CSCs in the fetal aorta, which do not reach critical values ​​against the background of "zero" and reverse diastolic blood flow in the umbilical artery.

A.N. Strizhakov (15).

Studies in the aorta of the fetus during pregnancy 32-41 weeks in pregnant women with preeclampsia of varying severity (79 people) were carried out when detecting a violation of blood flow in the umbilical artery - 38 people (48% of cases of the total number of examined). 21 people (55% of cases) with impaired blood flow in the aorta were identified, in all cases there was a pronounced fetoplacental insufficiency, clinically manifested by FGR of 2-3 degrees.

B.E. Rosenfeld (10).

Pathological ISS in the middle cerebral artery (22-41 weeks of pregnancy):

LMS - more than 4.4;

IR - more than 0.773.

Increased blood flow with a probability of 69.2% indicates the development of complications in the neonatal period.

Of particular interest is the increase in cerebral blood flow against the background of normal indicators of fetal-placental blood flow, hypoxia of extraplacental origin (decrease in hemoglobin, red blood cells, hypotension, etc.), which also leads to increased hypoxia with sdfd, complications in the early neonatal period.

Of considerable practical interest is the presence of normal parameters of cerebral circulation against the background of a pronounced decrease in placental blood flow. In these cases, a change in the pathological values ​​of cerebral blood flow to normal ones was noted. What is a sign of decompensation and may be due to heart failure and cerebral edema in the fetus.

Dynamic observation is important (great prognostic value for detecting fetal hypoxia).

B.S. Demidov (13).

According to the analysis of early neonatal pathology, the main cause of an isolated disorder in the internal carotid artery of the fetus (increased SDS over 7.0) can be:

1. Intrauterine infection - 21%.

2. Choroid plexus cysts of the lateral ventricles - 20%.

3.Ventriculomegaly - 4%.

4. No pathology on the part of the fetus in the early neonatal period - 12%.

Pathological manifestations in the early neonatal period.

1. Hyperexcitation of the central nervous system - 13%.

2. Pneumonia - 13%.

3. Insufficiency of cerebral circulation - 7.5%.

4. Tremor - 7.5%.

5. Skin-hemorrhagic syndrome - 15%.

1. Increasing DLS (peripheral resistance) is a high risk factor for complications in the neonatal period.

2. The most common cause of an increase in LMS is intrauterine infection.

3. Prolonged spasm of cerebral vessels plays an important role in reducing compensatory capabilities, which leads to disruption of adaptation processes in the early neonatal period.

B.E. Rosenfeld (10).

Mean value of uterine artery IR at 22-41 weeks of gestation.

1. Newborns born in normal condition - 0.482 ± 0.052.

2. Newborns born with initial signs of hypoxia in the early neonatal period - 0.623±0.042.

Pregnancy is very milestone in every woman's life. Every expectant mother begins to take care of the health of her baby already at the moment when he is in the womb. Modern medicine makes it possible to monitor the condition of the fetus at each stage of pregnancy with the help of an examination by a specialist, tests, and various diagnostic methods.

And if about ultrasound how mandatory procedure Everyone knows that dopplerometry often remains a blank spot. Ignorance usually leads to the fact that a woman refuses this type of diagnosis. What is it really? Is it necessary to do dopplerometry? In what trimester should this be done? additional examination? And how to decipher the received indicators?

Doppler is special kind ultrasound diagnostics, which provides the possibility of scanning and detailed assessment of vascular blood flow both in the child and in the mother's uterus.
The study, like the usual ultrasound, is based on the ability of ultrasound to reflect from tissues, but dopplerometry differs in one nuance - an ultrasonic wave reflected from moving bodies tends to change its natural frequency, and the sensor receives these waves with an already changed purity.

The equipment decodes the received data - and an image is obtained in color.
This diagnostic method is completely safe for the health of the baby and mother, it is highly informative, quite accessible, does not have side effects, is simple and reliable.

Conducting dopplerometry

The procedure is not much different from conventional ultrasound. The patient needs to expose her stomach, lie on the couch on her back and relax. Then the specialist diagnostician smears the stomach and a special sensor with a special gel to improve the conductivity of ultrasound, applies it to the woman's body and drives it over the skin, tilting it at different angles as necessary.

The difference from conventional ultrasound lies in the “picture” obtained using the study - if traditionally you can see a black and white incomprehensible image on the monitor, then with dopplerometry, red areas will mean blood flow, and blue ones will mean blood flow from the sensor. How brighter color on the screen, the more intense the movement of blood flow.

At the end of the study, the specialist draws up a conclusion based on the analysis of the data obtained and attaches a snapshot, if required. It is worth paying attention to the fact that the diagnostician makes a diagnosis only on the basis of his own research, and the attending physician - taking into account the totality of all examination methods.

Analyzed indicators

Traditionally, the following dopplerometry indicators are distinguished, according to which the specialist draws up a conclusion:

1. IR (resistive index): the difference between the highest and lowest velocity is divided by the highest recorded blood flow velocity.
2. PI (pulsation index): the difference between the highest and lowest speeds is divided by the average rate of blood flow per cycle.
3. SDO (systolic-distal ratio): the maximum blood flow velocity at the moment of cardiac contraction is divided by the velocity during the “rest” of the heart.

Doppler norms are usually divided by weeks, the indicators can be considered in the tables below.

Table No. 1. Norms of IR for the uterine artery.

Table No. 2. LMS norms for the umbilical artery.

Table No. 3. Norms of IR for the umbilical artery.

Table No. 4. LMS norms for the aorta.

LMS in the uterine artery should be close to 2.

PI in the uterine artery is ideally 0.4-0.65.

It is worth noting that the greatest importance is attached to indicators in the third trimester of pregnancy, because at this time any deviation from the norm can be fatal, and medical assistance in other cases should be provided immediately.

Assistance in reading the conclusion

Very often, it is quite difficult to understand the numbers, but even comparing the obtained indicators with the normal options, the patients ask themselves the question - what does this mean and what threatens? To answer these questions, a competent interpretation of the results is needed.

Signs of fetal hypoxia on dopplerography

High levels of LMS and IR in the arteries of the uterus probably indicate hypoxia. Elevated IR and LMS in the umbilical cord proves the presence of preeclampsia and vascular pathology. High numbers of LMS and IR in the aorta also emphasize the abnormal state of the child in the uterus, often in this case the baby needs to be given medical assistance. Elevated indices of IR and LMS in the umbilical artery and aorta of the fetus usually indicate an Rhesus conflict, an overbearing child, or the presence of diabetes in the mother.

Low rates of IR and LMS also indicate a danger to the life of the child.. This is usually the result of a low blood supply to the fetus, which affects only the most necessary organs of the baby. To stabilize the condition, urgent medical intervention is also necessary, otherwise a fatal outcome is likely.

Indicators are especially important for multiple pregnancies, because doctors are interested in whether children receive oxygen from their mother in the same way. The LMS and IR values ​​in the umbilical artery will be higher in the child who receives less oxygen as a result.

Reasons for getting tested

This type of examination allows physicians to control blood flow in the uterine and umbilical arteries, as well as in the fetal aorta, cerebral and carotid arteries.

This type of ultrasound diagnosis may seem like a whim, but in fact, the optimal blood supply to the fetus, its oxygen supply, and hence the timely development of the child in the womb, depend on proper blood flow.

Pathologies detected in time using this method are the key to saving the life of the child. Sometimes, to stabilize the condition of the fetus, it is enough to adjust the lifestyle or taking certain drugs, in some cases, the intervention of medical personnel may be necessary. But be that as it may, it is possible to learn about vascular anomalies of this kind only with the help of dopplerometry.

Of course, dopplerometry is not a mandatory diagnostic method during pregnancy. A woman can make an ultrasound diagnosis with dopplerometry by own will a couple of times before the baby was born. However, there are cases in which the attending physician strongly recommends this way evaluation of the fetus.

Indications for diagnosis

twin ultrasound 10 weeks

First of all, the specifics of this type of examination does not allow it to be carried out before the 18th week of pregnancy, because it is at this time that the placenta is finally formed. At an early stage, such a study is simply not informative. Usually, doctors recommend diagnosing with this method for the first time at 20-22 weeks of pregnancy (in the second trimester).

But there are also certain indications in which dopplerometry becomes a mandatory step. Usually they are the following:

1. Pregnancy at an early age.
2. The mother-to-be is an old-bearer.
3. Low water.
4. Polyhydramnios.
5. Ultrasound had previously diagnosed an umbilical cord wrapped around the baby's neck.
6. Slow fetal development.
7. Any suspicion of malformations of the child.
8. Infectious diseases of the mother.
9. Some chronic diseases of the mother, such as diabetes, hypertension, lupus.
10. The presence of several embryos in the uterus.
11. Interrupted previous pregnancy (reasons: miscarriage or missed pregnancy).
12. Malformations in previous children, if any.
13. Abdominal injury of any kind.
14. Rh factor conflict between mother and fetus.

Preparation for the examination

Since such an ultrasound is traditionally performed abdominally (through abdominal wall), so as not to harm the baby, then special preparation from a pregnant woman is not required. It is enough to carry out the simplest hygiene procedures, as well as visit the diagnostic room in a state of calm.

It is important to note that the bladder does not need to be filled, and it is also forbidden to take medications, unless circumstances require it.

Is this diagnostic method dangerous?

The absolute safety of dopplerometry (as well as conventional ultrasound) has long been proven by experts.

First, ultrasound cannot harm either the mother or the baby.

Secondly, ultrasound examination not fraught with any consequences for the human body.

Thirdly, the abdominal method excludes possible injuries, as it is as painless and accurate as possible.

Fourthly, dopplerometry itself is possible thanks to a technological breakthrough and depends on the capabilities of the equipment in the diagnostic room, and not on any special manipulations by the doctor, therefore it is also safe.

Pathologies

Traditionally, such an ultrasound makes it possible to track the following anomalies:

1. Oxygen starvation of the fetus.
2. Insufficient oxygen intake by one of the children during multiple pregnancy.
3. Vascular pathologies.
4. Deviation in the development of the child.

What to do after receiving the conclusion?

Comparison of the obtained indicators with the figures of the norm and self-decryption are useful skills, especially if you urgently want to know the result of the examination, because we are talking about the health of the child. But in no case can not be considered that this information will be enough. Moreover, there is no guarantee that you will be able to do it correctly.

The conclusion of an ultrasound scan with a preliminary diagnosis must be shown to the attending gynecologist, and only he can and has the right to draw final conclusions.

It is very important, when reading the results of dopplerometry on your own, not to take any medications without consulting a doctor!

Is there a possibility of medical error?

Since ultrasound diagnostics is performed by a person, the human factor cannot be ruled out. But dopplerometry is still done “in color”, and the probability of error here is extremely small, especially since the examination is performed by a qualified experienced specialist. Incorrect results can only be obtained on faulty hardware. If the patient has suspicions, she can always do an ultrasound in another diagnostic room.

Dopplerometry is a very important type of ultrasound diagnostics with enhanced capabilities due to the technological revolution in medicine. Such a study allows you to control blood flow in the vessels and aorta, and hence the condition of the unborn child, which is not only useful, but also extremely necessary in some cases. Sometimes only thanks to dopplerometry it is possible to detect extremely severe pathologies and react in time to save the life of the baby and even the mother.

Simplicity, accessibility, safety and informativeness - this is what characterizes this type of ultrasound. Pregnant women should not underestimate the importance of this method. Even in the absence of direct indications for this method, it is worth doing dopplerometry at least several times during the entire period of pregnancy in order to independently verify the health of your child.

The Doppler effect is based on the change in the frequency of the signal when reflected from moving objects, compared to the original. In this case, a signal is recorded in the form of a Doppler spectrum, that is, oscillations with different frequencies are “counted” for a certain time period and displayed in the form of luminous points of different intensity, which depends on the number of particles moving at the same speed. Since the Doppler effect allows you to estimate the speed of movement with great accuracy, in ultrasound (US) diagnostics, it is used to assess blood flow in the vessels. Such a study is called dopplerometry, or Doppler ultrasound, and can be carried out in two modes:

1. Permanent wave(there is a constant emission of ultrasonic signals)
2. Pulse(radiation goes in cycles of pulses).

In addition, it is possible to use color doppler mapping (CDI), consisting in the registration of blood flow velocities, coded in different colors, and superimposed on a conventional two-dimensional ultrasound image. The resulting images are called cartograms.

information Dopplerometry is becoming more and more widespread in obstetrics, as it allows using non-invasive(atraumatic, bloodless) ultrasound procedure to determine the condition of a pregnant woman and a child.

Norms of Doppler ultrasound during pregnancy

Violations in the utero-placental-fetal system occur due to improper implantation gestational sac and further development of the placenta, when changes in the spiral arteries do not occur in full. Doppler ultrasound abnormalities in the uterine arteries appear as a decrease in the diastolic component (exceeding the 95th percentile of normal). An important advantage of Doppler ultrasound is the ability to predict fetal-placental blood flow disorders based on IR (that is, development can be assumed, etc., and adequate prevention can be carried out).

After studying the uterine arteries, the umbilical cord arteries and fetal vessels (aorta and middle cerebral artery) are examined. This is necessary for a cumulative assessment of the severity of blood flow disorders in the mother-placenta-fetus system, as well as understanding compensatory possibilities(adaptive reaction of the body in response to the action of a damaging factor). The middle cerebral artery is examined using color doppler. The indications for the study of fetal-placental blood flow are generally similar to the indications for the study of blood flow in the uterine arteries (plus, non-immune fetal dropsy, congenital malformations, anomalies of the umbilical cord vessels, pathological types of cardiotocograms, and others). To assess the fetal-placental blood flow, a number of indices are used:

Normally, the blood flow is the same in both arteries of the umbilical cord (each artery carries blood to about half of the placenta, so the difference in indicators should alert the doctor in terms of unilateral disturbances in the vascular network). Normal indicators of IR of the umbilical arteries are presented in the table.

Violations determined by dopplerometry

Violation of blood flow in the fetal-placental system with Doppler ultrasound is manifested by an increase in the vessels of the umbilical cord and aorta above normal values, while a study of blood flow in the middle cerebral artery of the fetus notes a decrease in indices below standard values. This is explained centralization of blood flow(that is, the blood supply to the vital organs of the fetus in the first place - the brain, heart, adrenal glands). Thus, dopplerometry of the vessels of the fetal-placental part of the blood flow allows at an earlier stage to determine changes in blood flow and to conduct timely therapy or careful delivery in the absence of the effect of treatment.

Classification of disorders of the utero-placental-fetal blood flow (according to Medvedev):

Idegree:

BUT- violation of the uteroplacental blood flow while maintaining the fetal-placental;

B- violation of the fetal-placental blood flow with preserved uteroplacental blood flow;

IIdegree: simultaneous violation of uteroplacental and fetal-placental blood flow, not reaching critical values;

IIIdegree: critical disorders of fetal-placental blood flow with preserved or impaired utero-placental blood flow.

There is a direct relationship between the degree of blood flow disturbance and the frequency and severity of complications (, intrauterine hypoxia), as well as the condition of the newborn. Each degree has its own characteristics of pregnancy management:

At I degree - dynamic monitoring and therapy that improves blood flow with mandatory control (cardiotocography - recording of the fetal heartbeat), ultrasound and dopplerometry 1 time in 5-7 days. In the absence of deterioration, the pregnancy is prolonged until the term of delivery. If the indicators worsen, daily monitoring of CTG and Doppler ultrasound is mandatory and, if necessary, early delivery. At normal condition fetus possible childbirth perviasnaturalis(through the natural birth canal).

At II degree - CTG and dopplerometry are performed 1 time in 2 days, also with adequate therapy. With a deterioration in performance, the question of early delivery is raised.

III degree of violations is most often a direct indication for early delivery.

In addition to studying blood flow in the vessels, Doppler ultrasound is used to doppler echocardiography(study of blood flow in the fetal heart in utero). This method currently comes out on top in the study of hemodynamics in the fetal heart, while using color doppler and pulse Doppler with an assessment of three main parameters: speed, direction and nature (homogeneity, turbulence) of blood flow. This method allows you to identify the most complex congenital heart defects.

Doppler echocardiography is performed according to the following indications:

• fetus and other pathological conditions of the fetus, where the assessment of intracardiac hemodynamics is an important prognostic sign;
• Abnormal image of the heart on conventional ultrasound;
• Clarification;
• Determining the nature and severity of hemodynamic disorders;
• Presence of cardiac arrhythmias;
• Expansion of the chambers of the heart during routine ultrasound.

Dopplerography is also used for suspected extracardiac (non-cardiac) anomalies:

• Aneurysm of the vein of Galen (large cerebral vessel);
• Congenital malformations of the lungs, abdominal organs and kidneys;
• placenta accreta(a pathology in which the placenta grows into the wall of the uterus and does not separate spontaneously in the third stage of labor);
• Vascular anomalies(single umbilical artery and vasa previa).

Color Doppler and pulse Doppler are also used to diagnose such a serious pathology as hydatidiform mole, which is a special case trophoblastic disease (TB). TB is one of the most dangerous pathologies that usually manifests itself in the first trimester of pregnancy and can lead to the appearance of a malignant neoplasm ( chorioncarcinoma), which previously led to very high mortality. With this pathology, the normal development of the embryo does not occur, and the placenta grows in the form of bubbles that are filled with fluid. The most serious in terms of predicting the development of a malignant tumor is invasive(invasion - penetration into surrounding tissues) hydatidiform mole when abnormal tissue grows into the wall of the uterus. Since these structures are well supplied with blood, color flow has become widely used for diagnosis, which makes it possible to more accurately establish the diagnosis and carry out the necessary treatment.

Is Doppler Ultrasound Harmful?

Currently, there is a trend towards the use of technologies in ultrasound diagnostics that require high radiation power (this also applies to Doppler studies). Therefore, the issue of ultrasound safety is very acute, especially in pregnant women. Each ultrasonic sensor in the accompanying documentation contains the characteristics of the device for each mode of operation. In addition, there are regulatory documents that reflect the maximum allowable impact on tissues of ultrasonic waves. Ultrasound specialists should be guided in their work by the principle ALARA(As Low As Reasonably Achievable - as low as reasonably achievable), that is, each specialist must understand the capabilities of the device, but use them when the benefits outweigh the possible harm. To do this, on a number of devices indicators are installed:

• Thermal index(warns of possible overheating of tissues during the study). This index is especially important in the study of bone tissue (the second and third trimester of pregnancy - the study of the bones of the skull, spine, limbs of the fetus), since it is most susceptible to heating.
• Mechanical index(This index evaluates non-thermal processes in tissues during ultrasound - cavitation, which can cause potential tissue damage).

There is no exact data on the dangers and safety of ultrasound and, in particular, dopplerometry, since studies are not conducted on humans, but in the aquatic environment and on experimental animals. That's why, potential risk research should be less useful information received.

Additionally The Doppler effect and techniques based on it have received wide application in obstetric practice, as they allow not only to detect pathology in the mother-placenta-fetus system, but also to predict possible complications of pregnancy.

Doppler for pregnant women is a highly informative, accurate and safe research method used in obstetrics to diagnose circulatory disorders in the uterus, umbilical cord and fetal vessels.

With the help of this examination, it is possible to determine whether the blood flow is normal, or there is a violation of it from a minimum to a level where it urgently threatens the life of the fetus.

Dopplerometry during pregnancy is based on the property of an ultrasonic wave, reflecting from moving bodies, to change the frequency of its oscillations. As a result, a sensor that sends one type of sounds perceives them reflected with a different frequency, this is decoded by the program, and an image appears on the screen in the form of a graph, gray-white or color picture.

What is Doppler Ultrasound During Pregnancy?

Exploration Modes

1. Continuous Wave: The ultrasound is sent in a continuous waveform.
2. Pulse mode of ultrasound with Doppler during pregnancy: the wave is not sent constantly, but in cycles. As a result, the sensor captures the reflected ultrasound, sends it for processing, and at the same time “gives out” a new “portion” of signals.
3. Dopplerography during pregnancy can also be performed in color mapping mode. It is based on the same method, only the blood flow velocity in different parts of the vessels is coded in different colors. These shades are superimposed on a two-dimensional image that can be seen with conventional ultrasound. That is, if on the monitor you see various colors, these are not arteries (red) and veins (blue) at all, but vessels with different speed flow, which can be directed away from the sensor and towards the sensor.

In what cases are they researching

• uterine arteries
• umbilical artery
• fetal middle cerebral artery
• aorta of a developing baby.

The umbilical cord arteries are the most studied vessels. It is with changes in the speed characteristics in them that the oxygen supply to the fetus suffers.

The nature of the blood circulation in them allows us to judge the fetal-placental blood flow, microcirculation in that part of the placenta that directly supplies the fetus with blood.

Data decryption

Doppler for pregnant women evaluates blood supply based on the following indicators:

1. The systolic-diastolic ratio (SDO or S / D) is an indicator that will turn out if top speed in the vessel in systole (when the heart contracts) divided by the final diastolic (when the heart muscle "rests") speed. The indicator for each vessel has its own meaning.
2. Dopplerometry during pregnancy also evaluates the "resistance index" (IR) indicator. It is obtained by dividing the difference between the maximum (systolic) and minimum blood flow velocities by the maximum velocity.
3. PI (pulsation index): if you divide the difference between the maximum and minimum speeds by the average blood flow velocity over a complete heart cycle.

All three of these indicators are called "vascular resistance indices" (VRIs). These are the main “whales” for assessing the state of blood flow. In order to evaluate them correctly, a specific indicator for each vessel is compared with normative tables, taking into account the gestational age.

How to make sense of all these numbers

The placenta communicates with the uterus through the terminal villi. These are branches that have a huge number of vessels and are the main place where oxygen and nutrients pass to the fetus, and waste products are removed.

If the pregnancy is proceeding normally, dopplerography does not show changes. As soon as there is a decrease in the number of vessels in these villi due to various reasons(this is called feto-placental insufficiency), vascular resistance in the umbilical artery increases, LMS and IR increase.

Normally, Doppler ultrasound during pregnancy determines them as follows:

1. IR of the umbilical cord arteries:

• weeks 20 to 23: 0.62-0.82
• 24-29 weeks: 0.58-0.78
• 30 to 33 weeks: 0.521-0.75
• 34-37 weeks: 0.482-0.71
• 38-40 weeks: 0.42-068.

2. Systolic-diastolic ratio in the umbilical artery

If the uteroplacental blood flow suffers, then similar increases in ASC, visible on Doppler ultrasound during pregnancy, will be noted in the uterine arteries. According to the indicators of the blood flow of the uterine arteries, it is judged whether there will be an intrauterine growth retardation in a child.

3. Norm of LMS in the uterine arteries

4. PI in the uterine arteries in the III trimester, which allows Doppler: 0.40-0.65.

On the video: dopplerometry of a pregnant woman

5. Average IR in the uterine arteries in the third trimester: 0.3-0.9.

If, as a result of a decrease in blood flow in the vessels of the placenta and / or uterus, the child already begins to suffer, this can be detected by changes in the ASC in the fetal aorta. Then you will see that these numbers are more than the standard values ​​calculated for Doppler ultrasound during pregnancy:

6. LMS in the fetal aorta:

• 16-19 weeks: 6.06-6.76
• 20-22 weeks: 5.38-6.2
• from 23 to 25 weeks: 4.86-5.24.

7. IR in the fetal aorta: the average is 0.75.

If the fetal blood supply is so affected that instead of developing, it remains only to maintain its vital activity, this can be seen by an increase in IR and LMS of the carotid and cerebral arteries of the fetus.

8. IR of the middle cerebral artery at 22 weeks and before delivery: normal - 0.773.

9. LMS of the cerebral middle artery (for a period of 22 or more weeks): the norm is more than 4.4.

10. IR carotid internal artery fetus, which determines the dopplerography during pregnancy:

• 23 to 25 weeks: 0.942
• 26-28 weeks: 0.88-0.90
• 29-31 weeks: 0.841-0.862
• 32-34 weeks: 0.80
• from 35th to 37th week inclusive: 0.67-.85
• more than 38 weeks: Doppler during pregnancy shows a norm of 0.62-0.8.

What pathologies are detected

1. Preeclampsia. In this condition, dopplerometry during pregnancy usually first shows an increase in IR and LMS in the uterine arteries, then the same changes occur in the umbilical cord arteries.
2. In case of overgestation, Rh conflict and diabetes mellitus in the mother, Doppler ultrasound during pregnancy will show an increase in IR and LMS in the umbilical artery and aorta of the child.
3. If the pregnancy is multiple, and at the same time the fetuses develop unevenly, then dopplerography during pregnancy will show increased performance IR and LMS in the artery of the umbilical cord of the fetus, developed worse. If the indicators are the same for both fetuses, but one of them lags behind in development, this means that in this case there is a transfusion syndrome.

Also, Doppler ultrasound during pregnancy not only helps to establish a diagnosis of circulatory disorders at some level in the “fetus-placenta-mother” system, but also to establish its degree. In case of detection of a high degree of violations of the uterine-fetal-placental circulation, depending on the situation, it can be prescribed as mandatory treatment and emergency delivery.

About the cost of the examination

The price of a doppler ultrasound during pregnancy ranges from 1,000 to 3,500 rubles, you can conduct a study in specialized centers, in some maternity hospitals. If you have the special indications mentioned above, then Doppler ultrasound during pregnancy should be prescribed by an obstetrician-gynecologist and carried out under the conditions of medical genetic consultations on expert-class devices.

Thus, doppler for pregnant women is informative and objective method diagnosis, which must be evaluated by a doctor who observes your pregnancy. It helps not only to identify pathology in the vessels of the fetus, uterus and placenta in time, but also to make a prognosis, to assess the degree of blood flow disorders. You should not take risks when you see the “bad” conclusion of an ultrasound doctor and try to decipher the results yourself: it’s quite difficult to figure it out, and sometimes the bill goes “by the clock”.

Granuloma of the tooth - inflammation of the tissues near the tooth root. Treatment is carried out by a dentist, an additional decoction is used

Granuloma of the tooth - inflammation of the tissues near the tooth root. Treatment is carried out by a dentist, an additional decoction is used

Granuloma of the tooth - inflammation of the tissues near the tooth root. Treatment is carried out by a dentist, an additional decoction is used

Granuloma of the tooth - inflammation of the tissues near the tooth root. Treatment is carried out by a dentist, an additional decoction is used

cerebral arteries have their own, although to some extent variable, zones of blood supply, in connection with which a certain cerebral symptomatology is characteristic of their shutdown.

Anterior cerebral artery(PMA) - a branch of the internal carotid artery, connects with the anterior cerebral artery of the other side through the anterior communicating artery (see Fig. 1.1.4), supplies the cortex and the underlying white matter of the external marginal and medial part of the frontal and parietal lobes of the brain and the paracentral lobule, fornix, part of the head of the caudate nucleus located between them (Fig. 1.7.7).

When the branches of the anterior cerebral artery are switched off, the main symptoms are contralateral paresis and sensitivity disorders of the pedocrural type, i.e. with a predominant lesion distal departments legs.

The largest part cerebral hemispheres supplies middle cerebral artery(Fig. 1.7.8) - branch of the internal carotid artery: outer surface and subject white matter, except for the marginal part (ZMA and ZMA zone). Its medial - perforating branches pass through the anterior perforated space and go to the anterior and posterior legs of the internal capsule, into the shell, the outer part of the pale ball and to the body of the caudate nucleus (lenticulo-striatal arteries; see Fig. 1.7.8).

When the cortical branches of the middle cerebral artery (MCA) are switched off, a contralateral uneven plegia occurs. The brachifacial zone is predominantly affected. i.e. a person, namely: Bottom part facial muscles, as well as the tongue, arm and, to a lesser extent, leg, especially its distal parts (ACA zone).

Sensitivity drops out in the same way. With left-hemispheric lesions, motor and often sensory speech and praxis are disturbed; with right-hemispheric lesions, gnostic disorders develop.

Switching off of the deep branches of the middle cerebral artery due to damage to the internal capsule - its knee and posterior leg, where the fibers of the pyramidal tract lie compactly, leads to contralateral hemiplegia with deep defeat both arms and legs, as well as to central paralysis of facial muscles (VII pair) and tongue (XII pair).

The posterior part of the hind leg, where the sensory pathways pass, is usually also affected, which is manifested by hemia-nesthesia. Quite often, the reciprocal segment of the internal capsule with visual radiation passing through it is also affected, as a result of which hemianopsia develops.

Total shutdown of the middle cerebral artery leads to the development of a coma.

Posterior cerebral artery(ZMA) supplies the occipital-temporal region (spur groove, hippocampus, wedge), the posterior part of the visual tubercle, thickening of the corpus callosum, III and the back of the lateral ventricles (Fig. 1.7.6). material from the site

Deep subcortical-stem branches supply the quadrigemina, part of the tegmentum and base of the midbrain, red nucleus, substantia nigra, lateral geniculate body, and optic tract. Depending on the shutdown of certain branches of the posterior cerebral artery, homonymous hemianopsia, upper or lower quadrant hemianopsia, amnestic, and sometimes sensory aphasia, alexia can occur.

With damage to the deep branches of the posterior cerebral artery, either the lower red nucleus syndrome occurs - Claude's syndrome, in which the oculomotor nerve suffers on the side of the lesion, and on the opposite side there are cerebellar symptoms such as hemiataxia, intentional trembling, or upper syndrome red nucleus: damage to the oculomotor nerve and contralateral - extrapyramidal disorders, in particular choreoathetosis (Benedict's syndrome), thalamic syndrome (transient hemiparesis, persistent hemianesthesia with hyperpathy, etc.).

From the third cerebral bladder develops midbrain, which includes the legs of the brain, location, ventrally (anteriorly) and the roof plate, or quadrigemina. The cavity of the midbrain is cerebral aqueduct(Sylvian aqueduct). The roof plate consists of two upper and two lower mounds (tubercles), in which the nuclei of gray matter are laid. The superior colliculus is associated with the visual pathway, the inferior colliculus with the auditory pathway. From them originates the motor path going to the cells of the anterior horns of the spinal cord. On a vertical section of the midbrain, three of its departments are clearly visible: roof, tire and base, or actually the legs of the brain. Between the tire and the base is black matter. There are two large nuclei in the tire - red nuclei and nuclei of the reticular formation. The cerebral aqueduct is surrounded by a central gray matter, in which the nuclei of the III and IV pairs of cranial nerves lie. The base of the legs of the brain is formed by the fibers of the pyramidal pathways and pathways connecting the cerebral cortex with the nuclei of the bridge and the cerebellum. Systems are in the tire ascending paths, forming a bundle called medial (sensitive) loop. The fibers of the medial loop begin in the medulla oblongata from the cells of the nuclei of the thin and sphenoid cords and end in the nuclei of the thalamus. Lateral (auditory) loop consists of fibers of the auditory pathway, going from the pons to the lower colliculus of the quadrigemina and the medial geniculate bodies of the diencephalon.

Physiology of the midbrain

The midbrain plays an important role in regulation of muscle tone and in the implementation adjusting and rectifying reflexes which enable standing and walking.

The role of the midbrain in the regulation of muscle tone is best observed in a cat that has had a transverse incision made between the medulla oblongata and the midbrain. In such a cat, the tone of the muscles, especially the extensors, sharply increases. The head is thrown back, the paws are sharply straightened. The muscles are so strongly contracted that an attempt to bend the limb ends in failure - it immediately straightens. An animal placed on legs stretched out like sticks can stand. This condition is called decerebrate rigidity.

If the incision is made above the midbrain, then decerebrate rigidity does not occur. After about 2 hours, such a cat makes an effort to get up. First, she raises her head, then her torso, then she stands on her paws and can start walking. Consequently, the nervous apparatus for the regulation of muscle tone and the function of standing and walking are located in the midbrain.

The phenomena of decerebrate rigidity are explained by the fact that the red nuclei and the reticular formation are separated from the medulla oblongata and spinal cord by transection. Red nuclei do not have a direct connection with receptors and effectors, but they are associated with all parts of the central nervous system. Nerve fibers from the cerebellum, basal ganglia, and cerebral cortex approach them. big brain. The descending rubrospinal tract begins from the red nuclei, along which impulses are transmitted to the motor neurons of the spinal cord. It is called the extrapyramidal tract. The sensory nuclei of the midbrain perform a number of important reflex functions. The nuclei located in the superior colliculus are the primary visual centers. They receive impulses from the retina of the eye and participate in the orientation reflex, i.e. turning the head towards the light. In this case, there is a change in the width of the pupil and the curvature of the lens (accommodation), which contributes to a clear vision of the object.

The nuclei of the inferior colliculus are the primary auditory centers. They are involved in the orienting reflex to sound - turning the head towards the sound. Sudden sound and light stimuli evoke a complex alert response that mobilizes the animal for a quick response.

Fig 4. Transverse (vertical) section of the midbrain at the level of the superior colliculi.

The clinical picture in ICA occlusion depends on the state of collateral circulation. With complete preservation of collateral circulation, even with complete obstruction of the ICA, focal changes in the brain and clinical symptoms may be missing. This situation occurs with extracranial damage to the ICA. Small areas of infarction in the cortical-subcortical regions, mainly in the basin of the middle cerebral artery, are observed with collateral circulation insufficiency. In the case of an intracranial lesion of the ICA, dissociation of the large arterial circle of the brain occurs, as a result of which extensive foci of brain damage develop. In this case, pronounced neurological changes are observed. Often there is a fatal outcome.
It should be noted that the defeat of the internal carotid artery is more common in men.
In the acute form of circulatory disorders in the ICA basin, symptoms appear suddenly and quickly. The subacute form is characterized by a slower development of the clinical picture (usually within a few hours or I-2 days). In case of development of chronic or pseudotumorous form focal symptoms characterized by a slow increase (over several days or weeks).
Paresis of the extremities appears, as a rule, of the cortical type - with a more pronounced lesion of the arm on the side of the opposite affected artery. Sometimes only monoparesis occurs or only a violation of sensitivity is observed.
eye symptoms. At the onset of the disease, with a transient circulatory disorder in the ICA pool, a short-term or longer-term decrease in vision is observed. With persistent occlusion of the ICA on the side of the affected artery, a sharp decline vision or even blindness, which are due to the emerging ischemic opticopathy. At the end of the disease, atrophy is formed optic nerve. In some cases, damage to the organ of vision occurs in the form of acute obstruction of the CAS. In addition, ophthalmoplegia, impaired corneal sensitivity, hypotonia of the eyeball, Bernard-Horner syndrome can occur on the side of the ICA lesion.

Posterior cerebral artery syndrome
The posterior cerebral artery (PCA) supplies blood to the occipito-parietal region, the posterior and medial-basal regions of the temporal region, and also nourishes the posterior hypothalamic region, a significant part of the thalamic thalamus, the optic crown, the Lewis body and the thickening of the corpus callosum.
Circulatory disorders in these areas of the brain can occur due to occlusion of the PCA and its branches. In addition, the defeat of these areas may be due to changes in the main or vertebral arteries. In some cases, a combined lesion of the above vessels is possible. Due to the large number of anastomoses of the posterior artery with other cerebral arteries, total infarcts in its basin of the posterior artery almost never occur.
Clinical signs and symptoms. Complete occlusion of the PCA in the left hemisphere is accompanied by alexia and not pronounced sensory aphasia.
In the case of occlusion of the thalamo-geniculate artery on the opposite side of the focus, pronounced thalamic pain occurs, combined with hemihypesthesia or hemianesthesia, as well as hyperpathia. Transient hemiparesis develops on the opposite side of the focus. Hyperkinesis of atheroid or choreo-athetoid nature, hemiataxia, trophic and vegetative disorders occur.
Impaired circulation in the thalamo-perforating artery leads to severe ataxia and intentional tremor in the contralateral limbs. In some cases, instead of a tremor in the hand, choreoathetoid-type hyperkinesis or hemiballismus occurs. Sometimes a tonic setting of the hand develops - the “thalamic hand” (“obstetrician's hand”).
eye symptoms. With transient disturbances in the PCA basin, periodic blurring of vision, photopsia, micro- and macromorphopsia, and diplopia occur. At complete occlusion PCA and insufficient collateral blood supply from neighboring basins on the side opposite to the focus develops homonymous hemianopsia (half or upper quadrant). Sometimes metamorphopsia and visual agnosia occur. Since the cortical center of the macular region is supplied with blood from two cerebral arteries - the posterior and middle, visual acuity usually does not decrease. With occlusion of the thalamo-geniculate artery, the classic Dejerine-Roussy syndrome develops, characterized by contralateral homonymous hemianopia, in some cases in combination with miosis or Bernard-Horner syndrome, occurring on the side of the lesion.

basilar artery syndrome
In most cases, the precursors of complete occlusion of the basilar artery are short-term, repetitive signs of circulatory disorders in the vertebrobasilar system: dizziness, tinnitus, ataxia, dysarthria, dysphagia, transient paresis and paralysis of the cranial nerves.
Clinical signs and symptoms. Basically, there are symptoms of damage to the pons, which are accompanied by a disorder of consciousness up to coma. Bilateral paralysis of the trigeminal and facial nerves, paralysis of the limbs (ge-mi-, para- or tetraparalysis). The occurrence of bilateral pathological reflexes, symptoms of oral automatism, lockjaw is characteristic.
eye symptoms. Due to bilateral nuclear damage to the oculomotor, trochlear and abducens nerves, oculomotor disorders develop within a few hours or 2-5 days. In some cases, "cortical blindness" occurs.

Superior cerebellar artery syndrome
Clinical signs and symptoms. There are cerebellar disorders, which are the only manifestation of the disease in case of occlusion of the distal parts of the artery. In some cases, on the side of the focus, the development of a special hyperkinesis of the choreotic or athetoid type, disorders of pain and temperature sensitivity. On the opposite side, paralysis of the mimic muscles and hearing loss are often observed. Dysarthria, rhythmic myoclonus of the soft palate may occur.
eye symptoms. On the side of the lesion, Bernard-Horner syndrome develops; on the contrary, paresis of the trochlear nerve is observed on the opposite side. Nystagmus may occur.

Anterior villous artery syndrome
Clinical signs and symptoms. Due to damage to the posterior thigh of the internal capsule, the hippocampus, hemiplegia, hemianesthesia, and vasomotor disorders are observed in paralyzed limbs.
Eye symptoms caused by damage to the external geniculate body and nerve fibers passing as part of the Graziole bundle in the retro-lenticular part of the internal capsule. The development of contralateral homonymous hemianopsia is characteristic.

vertebral artery syndrome
Clinical signs and symptoms. The clinical picture depends on the level of damage to the vessel.
With occlusion of the intracranial vertebral artery due to a lesion medulla oblongata characterized by the development of alternating syndromes, which are persistent. It is possible to combine signs of alternating syndromes with symptoms of transient ischemia of the oral regions. brain stem. In most cases, Babinski-Najotte, Wallenberg-Zakharchenko, Avellis syndromes occur. With occlusion of both vertebral arteries, severe bulbar paralysis- dysphagia, dysarthria, dysphonia.
In the case of occlusion of the extracranial part of the vertebral artery, symptoms of a disorder occur in various zones of the vertebrobasilar system. There are vestibular disorders, disorders of statics and coordination of movements, dysarthria, motor and sensory disorders. Characterized by the appearance of impaired memory for current events.
eye symptoms, as well as general symptoms, depend on the level of occlusion of the vertebral artery.
When the intracranial artery is damaged, eye manifestations of Babinski-Najotte syndromes occur (ptosis, miosis, enophthalmos or only miosis on the side of the lesion, nystagmus towards the focus, sometimes heterochromia of the iris - a lighter iris on the side of the lesion), Wallenberg-Zakharchenko (ptosis, miosis, enophthalmos, pain in the eye, decreased sensitivity of the cornea on the side of the lesion, sweeping nystagmus), Avellis (miosis of varying severity).
In the case of occlusion of the extracranial region, oculomotor disorders and nystagmus occur. There is a decrease in visual acuity and a concentric narrowing of the visual fields. Photopsies develop. Characteristic appearance fatigue while reading.

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Middle cerebral artery syndrome
A pathological process in the basin of the middle cerebral artery (MCA) can occur both as a result of occlusion of the MCA itself, and an occlusive process in the internal carotid artery in the absence of a pronounced pathology in the MCA. It should be noted that occlusions of the MCA occur more frequently than lesions of other cerebral arteries.
Clinical signs and symptoms. With occlusion of the initial section of the MCA, hemiplegia occurs, as well as vasomotor disorders in the paralyzed limbs.
Damage to the left hemisphere of the brain leads to aphasia, agraphia, apraxia, alexia, acalculia and digital agnosia.
In the case of localization of circulatory disorders in the right hemisphere, anosognosia and autotopognosia are often observed.
With occlusion of the deep branches of the MCA due to damage to the subcortical nodes and the internal capsule, a syndrome of capsular hemiplegia occurs - damage to the facial and hypoglossal nerves, hemianesthesia and spastic hemiplegia on the opposite side.
When blood circulation is disturbed in the basin of the cortical branches of the MCA (anterior temporal, orbito-frontal, prerolandic, rolandic, anterior parietal, etc.), anosognosia, confabulations, body schema disorders are observed.
Eye symptoms characterized by contralateral homonymous hemianopia.

Syndrome of the arteries of the medulla oblongata
The syndrome occurs due to circulatory disorders in upper parts bulbar rope bodies, the upper part of the motor nucleus of the glossopharyngeal and vagus nerve, the upper halves of the bulbar olives, the central pathway of the tire, the descending root of the trigeminal nerve.
Clinical signs and symptoms. Characteristic development on the side of the focus of paralysis of the palatine curtain, larynx cross hemiparesis with impaired pain and temperature sensitivity, cerebellar ataxia.
eye symptoms. On the side of the lesion, either complete Bernard-Horner syndrome or only miosis occurs. When looking in the direction of the lesion, nystagmus occurs. Sometimes there are eye manifestations of the Babinski-Najotte syndrome - heterochromia of the iris.

Midbrain artery syndrome
The development of the syndrome is associated with occlusion of the paramedial arteries of the midbrain, which are branches of the posterior cerebral arteries that supply blood to the middle and medial parts of the legs of the brain, where the pyramidal tract, substantia nigra, red nucleus, superior cerebellar peduncle, nuclei of the oculomotor and trochlear nerves, posterior longitudinal bundle are located.
varied and depend on which artery is affected. The most common are ataxia and intentional trembling in the contralateral limbs. . With extensive, especially bilateral, strokes in the region of the midbrain, accompanied by damage to the nuclei of the reticular formation, disturbances of consciousness and sleep are observed, sometimes "peduncular hallucinosis" develops.
eye symptoms. Changes in the organ of vision are varied and depend on the level of occlusion. It should be noted that with this syndrome, oculomotor disorders are always observed.
When the base of the legs of the brain is damaged, the Weber-Gubler-Gendrin syndrome occurs (see above).
With damage to the posterior longitudinal beam, paralysis or paresis of the gaze develops, simultaneously with which, in some cases, nystagmus may occur.

Syndrome of carotid-cavernous fistulas
It develops as a result of an anastomosis between the internal carotid artery and the cavernous sinus. The cause of the anastomosis may be trauma, in some cases spontaneous development of the anastomosis is observed.
Clinical signs and symptoms. It is characterized by changes associated with a traumatic brain injury. In the clinical picture of the disease, changes in the organ of vision dominate.
eye symptoms. There is a syndrome of pulsating exophthalmos. With this syndrome, one- or two-sided exophthalmos is observed. Bilateral exophthalmos is caused by the inclusion of intersinus communications, when blood circulation from one cavernous sinus to another is carried out through the anterior and posterior intercavernous sinuses and unpaired basal choroid plexus. Very rarely, it is caused by a bilateral carotid-cavernous fistula. The degree of exophthalmos is different - from a barely noticeable protrusion of the eyeball to severe protrusion, in which the eyelids do not close over the eyeball. The reposition of the eyeball, as a rule, is carried out easily and only sometimes it is impossible due to severe local pain. After the pressure is released, the eyeball quickly returns to its original position. Pulsation of the eyeball is characteristic. Varicose veins develop mainly in the veins of the upper eyelid and eyebrows. The periorbital skin is edematous with a bluish tint. Conjunctival hyperemia, chemosis, expansion, tortuosity and pulsation are observed venous vessels eyeball and orbit with vibration phenomenon. The veins in the fundus are dilated, edema or atrophy of the optic disc is possible. Vision is reduced. Almost always, there is a deviation of the eyeball in both planes (especially outwards and downwards), which is explained by the highest concentration of dilated vessels on the upper and inner walls of the orbit. In addition to vascular changes, deviation of the eyeball may be associated with damage to the oculomotor nerves. Combined rather than isolated lesions of the III, IV and VI pairs of cranial nerves are more common. In the case of an isolated lesion, paresis of the abducens nerve occurs more often.
An important symptom of the development of carotid-cavernous anastomoses is the appearance of an acoustic phenomenon - the patient hears vascular noise in the head. The same noise is heard by the doctor during auscultation of the eyeball over the upper eyelid.
Quite rarely, with a carotid-cavernous anastomosis, the phenomenon of intermittent exophthalmos occurs - a rapid protrusion of the eyeball with compression of the jugular vein in the neck, coughing, straining, maximum flexion and extension of the head, and the same rapid disappearance of exophthalmos after eliminating the causes that caused venous stasis.
Often there is an increase on the side of the anastomosis intraocular pressure(IOP), and with de-compensated anastomosis sometimes - sharp rise IOP by type acute attack glaucoma. At the same time, against the background of exophthalmos, edema and tension of the tissues of the orbit, chemosis, corneal clouding, mydriasis and limitation of the mobility of the eyeball are rapidly increasing.
With carotid-cavernous anastomosis, a decrease in pressure in the CAS is characteristic, the degree of which depends on the severity of arteriovenous shunting.
This syndrome must be differentiated from a fracture of the base of the skull, a fracture of the bones of the orbit, a retrobulbar hematoma, a neoplasm, and an incipient phlegmon of the orbit.

Cerebral aneurysm syndromes
Arterial aneurysms occur due to congenital inferiority vascular wall. External factors leading to the occurrence of aneurysms are atherosclerosis, hypertension, rare cases infectious agents.
Due to the delay in the reverse development of arterio-venous connections that are present in the embryonic period, arterio-venous aneurysms are formed. They are characterized by the absence of capillaries and the direct entry of arterial blood into the veins. As a result of a sharp increase in blood flow, there is an expansion of arteries and veins with a simultaneous thinning of their walls.
In the clinical picture of arteriovenous aneurysms, the main symptoms are intracerebral hemorrhages and epileptiform seizures.
Clinical signs and symptoms arterial aneurysms depend on their shape and localization.
For the "paralytic" (tumor-like) form of aneurysms, their rather slow increase is characteristic, so the symptoms of cerebral compression develop slowly and are similar to the course benign tumors basal departments brain.
On the contrary, an acute sudden onset is characteristic of the apoplexy form. The first and main sign of an aneurysm rupture is a sudden acute headache. Almost simultaneously with it, nausea, repeated vomiting appear, there is a violation of consciousness; characterized by a rapid increase in the signs of meningeal syndrome. In some cases, epileptiform seizures occur and mental disorders develop. When examining the cerebrospinal fluid, blood is found. In the case of blood spreading into the ventricles of the brain, the disease is very difficult and usually quickly ends in death.
Eye symptoms arterial aneurysms are diverse and also determined by the location and type of aneurysms.
With unopened aneurysms of the vessels of the base of the brain, located in places of bifurcation and anastomosis of the vessels, lesions of the oculomotor, abducent, trochlear and trigeminal nerves occur. A congestive disc, primary or secondary atrophy of the optic nerves, retinal hemorrhages develop. There is exophthalmos. There is homonymous or bitemporal hemianopia.
For the apoplexy form of arterial aneurysms, the characteristic symptoms are congestive optic discs and oculomotor disorders.

Depending on the location of aneurysms of the internal carotid artery located within the cavernous sinus, there are several types of the course of the so-called syndrome:

• at anterior syndrome cavernous sinus, pain and impaired sensitivity occur in the zone of innervation of the branch of the trigeminal nerve, as well as paralysis of the oculomotor, trochlear and abducens nerves;
• middle cavernous sinus syndrome is characterized by a combination of lesions of the first and second branches of the trigeminal nerve and oculomotor and disorders and;
• in posterior cavernous sinus syndrome, oculomotor disorders occur simultaneously with the onset of pain and impaired sensitivity in the area of ​​innervation of all branches of the trigeminal nerve.

It should be noted that extradural hemorrhages occur when aneurysms located in the cavernous sinus rupture.
The most pronounced is ptosis - its development is preceded by a short period of diplopia and visual impairment. Subsequently, the function of the internal rectus muscle recovers faster. The function of the superior rectus muscle and the muscle that lifts the upper eyelid, on the contrary, recovers rather slowly. In addition to damage to the oculomotor nerve, it is possible to develop congestive optic disc, unilateral atrophy of the optic nerve on the side of the lesion, homonymous hemianopia.
Since aneurysms of the bifurcation of the carotid artery are located in the outer corner of the chiasm, homonymous hemianopia is observed during their development.
An aneurysm of the vertebrobasilar system due to compression of the formations of the posterior cranial fossa is characterized by the appearance of nystagmus, lesions of the trigeminal and facial nerves.
Clinical signs and symptoms of arteriovenous aneurysms depend on their location. The changes that occur may be transient. Often they are repeatedly repeated, which is associated with multiple hemorrhages that occur when arteriovenous aneurysms rupture. Most often (in 65% of cases) arteriovenous aneurysms are located in the cerebral hemispheres - a cup in the parietal and frontal lobes, less often in the deep, medially located structures of the brain (in 15% of cases) and in the posterior cranial fossa (in 20% of patients). They can be of various sizes - from microaneurysms to giant vascular conglomerates that cause compression and atrophy of adjacent areas of the brain.
Eye symptoms arteriovenous aneurysms are characterized various violations vision (hemianopsia), ophthalmic migraine, oculomotor disorders.

It is important for each person to know how he works. And one of the most interesting bodies for study is the brain, which has not yet been fully understood. Few, after a course of school biology, remember the functions of the midbrain and purpose. There is a need to deal with complex medical terms already in adulthood, when a person begins to visit doctors or is going to enter a medical university.

If you want to know what the midbrain is and where it is located, it is not necessary to study complex medical encyclopedias and study at medical school. Conscious patients before going to a medical facility want to learn more about the disease, and what functions the diseased organ performs. Then hospital procedures will not seem so frightening and incomprehensible.

Basic Information

The central nervous system contains neurons with processes and glia. The brain has only five sections. The first- oblong - continuation of the dorsal. It transmits information to and from other departments. Performs a regulatory function in relation to the coordination of movements. Second- bridge - here are the centers of the midbrain responsible for the assimilation of audio information and video information. This department stands for coordination of movements. Third- cerebellum - connects the posterior and anterior sections. Fourth- middle - responsible for facial expressions, movements of the eyeballs, auditory pathways pass through it. That is what we will consider. Fifth- front - normalizes mental activity.

It is interesting. Relationships between brain size and mental faculties does not exist in humans. Much more important is the number of neural connections.

Where is

The location corresponds to the name of the body. It is part of the stem. It is located under the intermediate and above the bridge. The formation of the human midbrain was influenced by the mechanism of perception of video information during the historical development of the organism. The process of evolution took place in such a way that the anterior section became the most developed. And through the middle one began to pass conductive channels of signals to various departments.

How does the midbrain develop?

Children in their mother's womb have to go through many stages of development. During the embryonic stage, the midbrain grows out of a small vesicle and remains intact throughout life. Throughout development, new cells appear in this part, they compress the cerebral aqueduct. With violations at this stage, problems with the cerebral aqueduct may develop - partial or complete blockage. One of the most dangerous consequences is such a dangerous disease as hydrocephalus.

Useful information. Every time after a person memorizes information, they form neural connections. This means that the structures various departments, including the midbrain, is constantly changing, it does not freeze in a certain state.

What role does

It is the middle section that regulates muscle tone. His role corresponds to his intermediate position. Due to the fact that the midbrain has a special structure, its functions include the transmission of information. It has a lot of different purposes:

• sensory- to convey tactile sensations;
• motor- coordination depends on this part of the midbrain;
• reflex- for example, oculomotor, reaction to light and sound.

Due to the work of the middle section, a person can stand and walk. Without it, a person would not be able to fully move in space. Also, work vestibular apparatus controlled at the level of the midbrain.

Organ device

It is known that the human midbrain has different parts, each of which performs its own role. Four hills - the structure is a pair of hills. The upper ones are visual and the lower ones are auditory.

There is a black substance in the legs. Thanks to him, a person not only lies, but can make precise movements with his hands and eat. At some point, the middle section processes information about when to bring a spoon to your mouth, how to chew food, and what function will allow you to swallow it.

Good to know: How does the diencephalon function and what is it for?

The ocular motor nerve originates between the legs, from where it exits. It is responsible for pupil constriction and some motor functions eyeball. To understand the structure of the midbrain, you need to know where it is located. It is composed of the intermediate and large hemispheres of the large brain, it is simple and has only two sections. The quadrigemina on the nearby two paired colliculi, which form the upper wall. They resemble a plate in appearance. Legs - there are conducting channels going to the hemispheres of the anterior section and connecting it with the lower parts of the nervous system.

How many parts does the middle section have

There are three parts in total. Dorsal - the roof of the middle section. It is divided into 4 mounds with the help of grooves intersecting in pairs. The two upper hills are subcortical centers of vision regulation, and the remaining lower hills are auditory. Ventral - these are the so-called legs of the brain. The conducting channels to the anterior section are based here. The inner space of the brain has the form of a hollow channel.

Useful information. If a person does not breathe oxygen for more than five minutes, the brain will be permanently damaged, leading to death.

Nuclei

Inside the tubercles of the quadrigemina, gray matter accumulates, the accumulations of which are called nuclei. The innervation of the eyes is called the main function of the nuclei. They are of the following types.

Reticular formation - takes part in the stabilization of the skeletal muscles. They activate the cells of the cerebral cortex of the head, and have an inhibitory effect on the spinal cord. oculomotor nerve - contains fibers that innervate the sphincter and eye muscles. Block nerve - supply nerves to the oblique muscle of the organ of vision. Black substance - the color is associated with the pigment melanin. The neurons of this substance themselves synthesize dopamine. Coordinate facial muscles, small movements. Red nuclei of the midbrain - activate the neurons of the flexor and extensor muscles

Prevention of pathologies

The brain without intellectual activity and physical activity cannot function correctly. Usually, malfunctions in the central nervous system are observed in people over 70 years of age. But diseases of this group are diagnosed in those who, after retirement, cease to maintain their health and lead a healthy lifestyle. However, there are also congenital pathologies in the midbrain, you can get sick at any age.

Good to know: How to improve blood circulation in the brain: recommendations, drugs, exercises and folk remedies

Exercise regularly to the best of your ability, go for walks fresh air doing gymnastics in the morning. Give up tobacco and alcohol. Switch to a healthy diet, eat as much as possible fresh vegetables and fruits. Do not eat foods with preservatives and emulsifiers. Train the mind - for this you can read books, solve crossword puzzles, play chess, gain new knowledge in a field of interest.

Get rid of beriberi - take vitamins and antioxidants. Since the brain is 60% fat, you can not refuse oil, but it must be natural. For example, olive oil is perfect. Avoid stressful situations. Do not engage in monotonous work too often, take breaks, switching to other activities. Monitor blood pressure levels - hypertension can cause a stroke.