screening methods. The difference between conventional ultrasound and screening

For all pregnant women, screening examinations began to be introduced as a mandatory procedure 20 years ago. The main task of such analyzes is to identify a genetic abnormality in the development of the unborn child. The most common include Down syndrome, Edwards, a violation of the formation of the neural tube.

Screening - what is it

All young mothers should know that screening is a word translated from English as “sifting”. According to the results of the study, a group is determined healthy people. All the rest are assigned tests that help determine the disease. A comprehensive examination consists of different methods, For example:

• mammography;
• genetic screening;
• CT scan etc.

All the technologies described above help in identifying diseases in people who are not yet aware of the presence of pathology. In some cases, these studies affect emotional condition of a person, not everyone wants to know in advance about the development of a serious illness. This devalues ​​the examination, especially if the patient is not going to be treated. IN modern medicine mass examinations are carried out only if there is a real danger to health a large number of people.

Screening during pregnancy

What is screening for expectant mothers? In this case comprehensive examination it is necessary to control the development of the fetus, assess the compliance with the norm of the main indicators. When talking about prenatal screening, then we are talking about ultrasound and biochemical examination, for which the sampling is carried out venous blood. You need to take it on an empty stomach early in the morning so that the substances that come with food do not change the composition. The screening test will show the level of fetal A-globulin, the pregnancy hormone, estriol.

Screening of pregnant women includes an ultrasound examination, which allows you to visually determine deviations in the development of the child. On ultrasound, the main indicators of the growth rate are visible - nasal bone, collar zone. To obtain the most reliable results of the study, the expectant mother must strictly and clearly follow all the rules of the perinatal examination.

How is pregnancy screening done?

Parents concerned about genetics and the risk of developing diseases in a child are interested in how screening is done. At the first stage, the doctor must accurately determine the period. This affects the norms biochemical indicators blood, the thickness of the collar space will vary greatly depending on the trimester. For example, TVP at week 11 should be up to 2 mm, and at week 14 - from 2.6 mm. If the deadline is not set correctly, the ultrasound screening will show an unreliable result. Donate blood should be on the same day that the ultrasound is performed, so that the data matches.

Biochemical screening

Most exact way obtaining an answer to the presence of chromosomal diseases - biochemical screening. Blood is taken on the same day as the ultrasound, early in the morning on empty stomach. Compliance with these requirements is very important in order to obtain a reliable test result. The sampling is carried out from a vein, the material is examined for the presence of a specific substance that the placenta secretes. The concentration, the ratio in the plasma of marker substances, special proteins is also estimated.

It is important to avoid violations during delivery to the laboratory, storage for research. At the reception, the girl will be given a questionnaire in which there are questions:

• about the presence in the family of the father of the child or her people with genetic abnormalities;
• whether there are already children, whether they are healthy;
• whether or not the expectant mother has diabetes mellitus;
• whether the woman smokes or not;
• information about height, weight, age.

Screening ultrasound

This is the first stage of examination of the expectant mother. Screening ultrasound is no different from any other ultrasound. During the procedure, the specialist assesses the general condition of the embryo, the rate of development of the child in accordance with the gestational age, the presence of pronounced malformations and any other external deviations. The absence of the latter does not indicate full health fetus, therefore, a biochemical blood test is performed for more precise study.

1st trimester screening

This is the very first screening during pregnancy, which should be carried out at 11-13 weeks of gestation. It is very important to correctly determine the gestational age in advance. The first appointment necessarily includes an ultrasound examination. The lab sometimes requests the results of an ultrasound scan in order to accurate calculations. A blood test is also carried out for protein and hormone: PAPP-A and free b-hCG. Such a test is called a "double test". If detected low level the first, then it may refer to:

1. The likelihood of developing Down syndrome, Edwards.
2. The possibility of developing anomalies at the chromosomal level.
3. The pregnancy stopped growing.
4. There is a chance of having a baby with Cornelia de Lange syndrome.
5. There is a risk of miscarriage.

An ultrasound will help the doctor visually assess the course of pregnancy, whether an ectopic conception has occurred, the number of fetuses (if there are more than 1, then there will be fraternal or identical twins). If the baby’s posture is successful, then the doctor will be able to assess the usefulness of the heartbeat, examine the heart itself, and the mobility of the fetus. A child at this time is completely surrounded by amniotic fluid, can move like a small fish.

Screening 2nd trimester

The second screening during pregnancy is carried out between 20-24 weeks. Again, an ultrasound examination, a biochemical analysis are prescribed, but this time the test is carried out for 3 hormones. To check b-hCG, a check for the rate of ACE and estriol is added. An increased indicator of the first indicates wrong definition term or multiple pregnancy, or can confirm the risk of developing genetic disorders, fetal pathology.

3rd trimester screening

The third screening during pregnancy under the program is carried out between 30-34 weeks. When doctors do an ultrasound, they evaluate the position of the fetus, the presence or absence of violations in the formation internal organs baby, is there an entanglement with the umbilical cord, are there any delays in the development of the baby. During this period, the organs are clearly visible, which helps to accurately identify and enable deviations to be corrected. Specialists assess the maturity of the placenta, the volume amniotic fluid can tell the gender of the baby.

Screening transcript

Each stage of pregnancy has certain indicators of the norm of the development of the child, blood composition. Each time the test will show compliance or deviation from the standard indicators. Screening is deciphered by specialists who evaluate the main indicators. Parents themselves are not required to understand the values ​​​​of TVP or the levels of hormones in the blood. The doctor who monitors the pregnancy will explain all the indicators in the results of the study.

Video: first trimester screening

Implementation of the screening method.

Screening - carrying out simple and safe research large population groups in order to identify risk groups for the development of a particular pathology.

This method is very important and allows you to identify various pathologies in the prenatal and neonatal periods, to achieve a reduction in the frequency of detection of common forms, an increase in the frequency of detection of early forms of cancer and an improvement in survival.

Prenatal screening - studies conducted by pregnant women in order to identify risk groups for pregnancy complications. Prenatal screening usually includes ultrasound and biochemical screening. According to the gestational age, screening of the first and second trimester is distinguished. Neonatal screening - mass examination of newborns for the most frequent congenital diseases. A drop of blood from the heel is taken from each newborn on a special test form, which is sent to the medical genetic consultation for research. If a disease marker is found in the blood, parents with a newborn child are invited to a medical genetic consultation for a second blood test to confirm the diagnosis and prescribe treatment. In the future, dynamic monitoring of the child is carried out. Neonatal screening provides early detection hereditary diseases and their timely treatment, to stop the development of severe manifestations of diseases leading to disability. Neonatal screening can prevent complications of diseases such as hypothyroidism, phenylketonuria, cystic fibrosis, galactosemia, adrenogenital syndrome.

Screening methods include lab tests, allowing you to determine the types of various infectious agents, ultrasound research methods, tomography, PCR, ELISA and many other tests.

The purpose of screening is high quality detection of pathology, but there are a number of problems here. False-positive and false-negative conclusions are a serious problem.

For a sufficient level of screening tests to be performed, a number of conditions must be met:

1. Informing the population about screening.

2. Providing reliable and high-quality accounting, storage and reproduction of information.

3. Principles of questioning the population. At the moment, a questionnaire has been created in Ukraine, which includes 20 questions. However, the answers cannot be used to make a decision in medicine, as they contain only the personal impressions of the respondents and do not coincide with the conclusions of qualified doctors.

4. Evaluation of any type of screening according to the criterion "medical efficiency-cost".

5. An important issue is the decision of who can evaluate the results and in whose interests the screening is carried out.

Screening is the identification of signs of the disease, before you feel any changes in your own condition, that is, objective symptoms appear. Screening is the main way to detect breast cancer in the early stages, when treatment has a favorable prognosis. Depending on age and the presence of risk factors, screening may consist of self-examination of the breast by you, examination during a regular visit to the doctor, mammography, etc.

Breast self-examination

Self-examination of the gland should begin at the age of 20 years. Then you will get used to the normal appearance and consistency of your breasts, you will be able to detect changes in it on early stage. If you find changes in your breasts, see your doctor as soon as possible. During the visit to the doctor, pay attention to these changes, and also show the doctor your technique for self-examination, ask any questions that interest you.

Doctor's examination

During the examination, the doctor will examine both breasts to look for nodules or other changes. It can detect changes that you missed on your own. He will also examine the axillary lymph nodes.

Mammography

This study is a series x-rays glands, and at the moment it best method studies to detect small tumors that cannot be determined by the hands of a doctor during palpation.

There are two types of this study.

Overview/screening images. Run regularly, once a year, they can be useful for detecting changes that have occurred in the hardware since the last snapshot.

Diagnostic snapshot. Performed to evaluate changes that you or your doctor detect. Good visualization may require several shots, including pinpoint shots of the suspicious area.

But mammography is not perfect. A certain percentage of cancerous tumors are not visible on x-rays, and sometimes they can even be determined by hand during palpation, but, nevertheless, are invisible in x-rays. This is called a false negative result. The percentage of such tumors is higher in women aged 40-50 years: the breasts in women of this age are denser and nodules can be distinguished in the picture against the background of more thick fabric glands are more difficult.

On the other hand, mammograms can show changes that look like a cancerous tumor when in fact there is none, this is called false positive results. Such errors lead to unnecessary biopsies, patient distress, and higher costs for healthcare facilities. The accuracy of the description of mammograms is significantly affected by the experience of the radiologist. But, despite some shortcomings of mammography as a screening method, most experts agree that this is the most reliable method screening for breast cancer in women.

During a mammogram, your breasts are placed between special plastic plates to keep them still while the image is taken. The entire procedure takes less than 30 seconds. Mammograms are usually not uncomfortable, but if you are concerned about something, tell the x-ray technician who takes the x-ray.

When scheduling your yearly mammogram and doctor's visit, visit your doctor first so that he can detect suspicious areas in your breast during the examination and write a referral to the radiologist in order to take a targeted x-ray.

Other screening methods

Mammography with computer-assisted image recognition (CAD, Computer-Aided Detection).

With traditional mammography, your images are viewed and described by a radiologist whose experience and qualifications mainly determine the accuracy of the diagnosis, in particular, the number of cases of small tumors missed in the images. In our case, the doctor is asked to first indicate to the program suspicious, in his opinion, areas, after which the program additionally highlights areas that are suspicious from her point of view. Of course, the program will never be able to replace the intelligence of a doctor, but teamwork human and computer can increase the number of breast tumors detected at the earliest stages.

Digital mammography.

It differs fundamentally from traditional mammography in the way the X-ray image is stored. From the very beginning, the picture is captured by a digital detector (like a digital photograph, without film) and later the doctor gets the opportunity to change the brightness of the image, to increase its individual sections. Digital shots can be transmitted over long distances, for example, from the province to major center for consultation with a specialist. Digital mammography is most relevant for women in their 40s and 50s as their breasts are more dense and the ability to change the brightness of the image is in high demand.

Magnetic resonance imaging (MRI).

This research method allows you to get an image of the entire mass of the breast, to make virtual layer-by-layer sections. In this case, instead of X-rays, a powerful magnetic field and a radio signal are used, in other words, this study does not give radiation exposure. MRI is not used for mass screening of breast cancer, but may be ordered to examine suspicious areas that are inaccessible to palpation due to their small size and are difficult to see on traditional mammograms. MRI does not replace, but complements traditional mammography.

MRI is not indicated for streaming breast cancer screening due to big amount false positive responses, leading to unnecessary biopsies and patient distress. This study is high-tech and expensive, the images require interpretation by an experienced radiologist.

According to the latest recommendations, MRI should be performed in all women with a first diagnosis of breast cancer. This may reveal the simultaneous presence of an additional tumor in the same gland or in a second breast not found on mammograms. However, there is no reliable data yet whether such a study reduces breast cancer mortality.

Breast ultrasound.

The method is used to additionally evaluate suspicious lesions visible on mammograms or on examination. used to obtain an ultrasound image. sound waves high frequency, that is, this study, like MRI, does not give radiation exposure. Ultrasound can reliably distinguish volumetric formations - cysts, that is, cavities with liquid, from nodes consisting of dense tissue. Breast ultrasound is not used for cancer screening due to the large number of false positive results It creates the appearance of disease where there is none.

New screening methods

flow lavage

In the external opening of the excretory duct of the mammary glands, located on the nipple, the doctor inserts a thin flexible tube, a catheter, through which he first injects a special solution, and then receives a suspension of cells, among which there may be atypical, cancerous ones. Most breast cancers begin their growth precisely from the lumen of the ducts of the glands, and indeed: atypical cells can be detected in lavage long before the first signs of a tumor appear on mammograms.

However, this method is a new and invasive intervention, for which the percentage of false negative results is not fully determined, and the relationship between the detection of cancer cells in lavage and the development of breast cancer is not fully understood. Until these questions are answered, ductal lavage cannot be recommended as a mass screening method.

Breast scintigraphy

New technology for detecting the smallest tumors in the mammary glands. You are injected intravenously with a special substance, an isotope radiopharmaceutical, which is distributed throughout the body and accumulates in the breast tissue. Recent studies have shown that this method helps to identify small tumors that were missed by mammography and ultrasound.

Taking a biopsy from a suspicious lesion detected by this method presents problems, but research is underway in this direction.

This study gives a small radiation load on the body; the examination requires compression of the breast, as in a mammogram. Women with dense breasts (because mammography is not effective enough for them) and women with high risk development of breast cancer. Depending on the results of the study, the place of this diagnostic method in a number of methods early diagnosis breast cancer. Probably, the method will become an addition to conventional mammography.

What is the difference between conventional ultrasound and screening, is there a difference between them? To answer this question, you need to know what screening is and whether it can differ from ultrasound.

Screening is the examination of a specific group of the population. It is carried out to reveal specific disease characteristic of a group of people or an area.

In other words, it is dispensary. It is under this word that screening is known to people who have undergone medical examinations at school and at enterprises.

Target this event- detection of diseases at an early stage, which makes it possible to start treatment on time and reduce mortality.

Screening equipment differs from the devices used in conventional diagnostics in lower accuracy, since the goal in this case will be the detection or exclusion of the disease.

There are mass medical examinations and selective ones, which are carried out in risk groups, for example, when not all family members in which there is a hereditary disease are examined, but only a few.

Prenatal screening, which is carried out during pregnancy, is the most famous. But there are other types of screening: children's and adult medical examination, annual mass screening for tuberculosis, etc.

Pediatric medical examinations are planned universal examinations of children. In children under one year old, they are carried out monthly, in children aged 3 to 18 years - annually.

Medical examination of adults is carried out once every 3 years, and some groups of citizens are required to undergo it annually.

Examples of such screening include mammography (examination of the breast), colonoscopy (examination of the bowel), and dermatological examination to detect skin cancer.

Newborn screening - this is the name of the mass examination of children in maternity hospitals using laboratory tests.

The aim is to detect hereditary diseases before their symptoms appear. Before being discharged from the hospital, a drop of blood is taken from the baby's heel and sent to a genetic laboratory for analysis.

In Russia, newborns are screened for phenylketonuria, congenital hypothyroidism, cystic fibrosis, galactosemia, and adrenogenital syndrome.

Screening improves the health of the population as a whole. It allows you to identify the disease at an asymptomatic stage, at which treatment is most effective.

Ultrasound examination

ultrasound or ultrasound examination is the study of any organ or tissue with the help of ultrasonic waves.

Ultrasound examination differs from other methods in safety, it does not violate the integrity skin, does not involve the introduction of foreign substances into the body, does not increase radiation background in the human body.

The method is considered absolutely safe, has no side effects and can even be used to study the fetus at any stage of pregnancy.

The study is carried out using the apparatus ultrasound diagnostics or scanner. Most types of ultrasound do not require special preparation.

Ultrasound is used in almost all branches of medicine. Ultrasound is used in ophthalmology, gynecology, pediatrics, therapy, urology, cardiology.

It is used to diagnose diseases of internal organs, abdominal cavity and retroperitoneal space, small pelvis.

This is an inexpensive and affordable study that allows you to diagnose many dangerous diseases with sufficient accuracy.

It also has a drawback - it is difficult to examine hollow organs with the help of ultrasonic waves.

Some types of ultrasound are included in the complex of mandatory studies conducted during medical examinations.

For example, ultrasound of the abdominal cavity is included in the list of mandatory examinations conducted in people over 39 years of age.

If we talk about the study of ultrasound, then here the female medical examination differs from the male. In women, the pancreas, kidneys, uterus, ovaries are examined.

In men, the pancreas, kidneys, prostate, and since 2015, smoking men of a certain age undergo a single ultrasound examination abdominal aorta to rule out an aneurysm.

An ultrasound examination conducted as part of such a screening makes it possible to detect neoplasms of internal organs that have not yet manifested themselves.

Now there are all possibilities for this survey, in any major city there is medical centers where to go for this.

The study can be done free of charge under the CHI program. The attending physician who ordered the ultrasound must explain in which institution it is carried out free of charge.

What is the difference between screening ultrasound and ultrasound?

Prenatal screening is a diagnostic examination of all pregnant women, which consists of a combination of ultrasound and blood tests. Screening ultrasound is performed in all pregnant women, regardless of their well-being.

What is the difference between an ultrasound as part of screening and just an ultrasound that a pregnant woman undergoes? Strictly speaking, nothing. In both cases, the study can be carried out on the same apparatus.

The difference is in the approach to deciphering the results of an ultrasound study.

During screening, ultrasound indicators are compared with the results of a blood test and conclusions are drawn regarding the development of the fetus based on the combination of these two studies, and with a conventional ultrasound, the doctor simply looks at the fetus or organ and writes a conclusion.

It is clear that the screening study is deeper, it helps to better examine the fetus.

Screening ultrasound is only one of the preventive measures, which along with biochemical analysis blood is included in prenatal screening.

Biochemical analysis reveals certain marker enzymes in the blood. Deviations from their normal concentration indicates malformations.

Such a complex allows you to assess the risk of congenital anomalies:

• Down syndrome;
• Edwards syndrome;
• defects in the brain and spinal cord.

During pregnancy, a woman undergoes two screenings, and if necessary, a third is also carried out.

The first diagnosis includes an ultrasound and a blood test for two hormones, the second - an ultrasound and an analysis for three hormones (triple test).

The last screening (third trimester) consists only of ultrasound, which is carried out on a high-precision "Expert" class apparatus.

During a routine ultrasound during pregnancy, you can examine not the fetus, but the organ of the expectant mother.

A pregnant woman can be sent for examination of the kidneys, liver, gallbladder, pancreas, blood vessels, glands.

Just an ultrasound during pregnancy is prescribed if there are indications for this, for example, a doctor suspects a pathology or a woman has any health problem.

In this case, she is prescribed an ultrasound as a normal patient.

In other words, technically, screening ultrasound and ultrasound during pregnancy are no different from each other. They just have different goals.

The main purpose of ultrasound during pregnancy is to determine the position of the fetus in the uterus and development.

The task of an ultrasound examination carried out as part of screening is to determine the possible pathology in a child.

This allows you to choose therapeutic measures or decide on the termination of pregnancy.

Now it is clear that the question of “what is the difference between screening and ultrasound” sounds incorrect.

It is impossible to say whether they are different or not, since ultrasound is just one of the studies that are included in the screening or carried out outside of it.