Introduction

diagnostics medical examination endoscopic

The last decade of the 20th century is characterized by the rapid development of radiology. The main reason for this is the emergence of a whole series of so-called "new technologies" that have made it possible to dramatically expand the diagnostic potential of the "old" traditional radiology. With their help, the concept of so-called white spots in classical radiology was essentially "closed" (for example, the pathology of the entire group of parenchymal organs of the abdominal cavity and retroperitoneal space). For a large group of diseases, the introduction of these technologies has dramatically changed the existing possibilities for their radiological diagnosis.

In many ways, it is due to the success of radiodiagnosis in leading clinics in America and Europe that the time for making a diagnosis does not exceed 40-60 minutes from the moment the patient enters the hospital. And we are talking, as a rule, about serious urgent situations, where delay often leads to irreversible consequences. Moreover, the hospital bed has become less and less used for diagnostic activities. All the necessary preliminary studies, and first of all radiation, are performed at the prehospital stage.

Radiological procedures in terms of the frequency of their use have long been ranked second, second only to the most common and mandatory laboratory tests. Summary statistics of major world medical centers shows that thanks to radiation methods, the number of erroneous diagnoses during the initial treatment of a patient today does not exceed 4%.

Modern means visualizations are as follows fundamental principles: impeccable image quality, equipment safety for both patients and medical staff, reliable operation.

The purpose of the work: to gain knowledge about instrumental methods of examining patients in x-ray, endoscopic and ultrasound studies.

Instrumental methods for X-ray, endoscopic and ultrasound examinations

Methods for studying the structure and functions of human organs using special equipment are called instrumental. They are used for the purpose of medical diagnosis. For many of them, the patient must be psychologically and physically prepared. The nurse must be proficient in the technology of preparing patients for instrumental examinations.

X-ray methods of research

X-ray (X-ray) examination is based on the property of X-rays to varying degrees to penetrate the tissues of the body. The degree of absorption of X-ray radiation depends on the thickness, density and physico-chemical composition of human organs and tissues, therefore, denser organs and tissues (bones, heart, liver, large vessels) are visualized on the screen (X-ray fluorescent or television) as shadows, and lung tissue due to the large amount of air, it is represented by an area of \u200b\u200bbright glow. Wilhelm Conrad Roentgen (1845-1923) - German experimental physicist, founder of radiology, discovered X-rays (X-rays) in 1895. On x-rays of the intestine with contrast, you can see - a change in the lumen of the intestine, an increase in the length of the organ, etc. (Annex 1).

Figure 1. X-ray room.

There are the following main radiological methods of research:

1. Fluoroscopy (Greek skopeo - to examine, observe) - X-ray examination in real time. A dynamic image appears on the screen, allowing you to study the motor function of organs (for example, vascular pulsation, gastrointestinal motility); the structure of organs is also visible.

2. Radiography (Greek grapho - to write) - X-ray examination with the registration of a still image on a special X-ray film or photographic paper. With digital radiography, the image is fixed in the computer's memory. Five types of radiography are used.

* Full-format radiography.

* Fluorography (small format radiography) - radiography with a reduced size of the image obtained on a fluorescent screen (Latin fluor - flow, flow); it is used in preventive studies of the respiratory system.

* Plain radiography - an image of the entire anatomical region.

* Sighting radiography - an image of a limited area of the organ under study.

* Serial radiography - sequential acquisition of several radiographs to study the dynamics of the process under study.

3. Tomography (Greek tomos - segment, layer, layer) - a method of layer-by-layer imaging that provides an image of a tissue layer of a given thickness using an X-ray tube and a film cassette (X-ray tomography) or with the connection of special counting chambers from which electrical signals are supplied on a computer (computed tomography).

4. Contrast fluoroscopy (or radiography) - an X-ray examination method based on the introduction into hollow organs (bronchi, stomach, renal pelvis and ureters, etc.) or vessels (angiography) of special (radio-opaque) substances that delay X-ray radiation, resulting in on the screen (film) receive a clear image of the studied organs.

Before conducting an X-ray examination, the area of the planned examination should be freed from clothing, ointment dressings, adhesive plaster stickers, ECG monitoring electrodes, etc., and asked to remove watches, metal jewelry and pendants.

X-ray examination of the chest organs is an important method for examining patients with diseases of the respiratory system and CVS.

Fluoroscopy and radiography are the most commonly used methods for examining the respiratory organs. X-ray examination allows you to assess the condition of the lung tissue, the appearance in it of areas of compaction and increased airiness, the presence of fluid or air in the pleural cavities. Special preparation of the patient is not required. The study is carried out in the position of the patient standing or, in a serious condition of the patient, lying down.

Contrast radiography of the bronchi (bronchography) is used to detect tumor processes in the bronchi, expansion of the bronchi (bronchiectasis) and a cavity in the lung tissue (abscess, cavity). A radiopaque substance is injected into the bronchial cavity.

Preparation of the patient for bronchography is carried out in several stages:

1. Conducting a test for individual tolerance of iodine-containing drugs (iodine test): within 2-3 days, as directed by a doctor, the patient is offered to drink 1 tbsp. 3% potassium iodide solution. Another option for conducting an iodine test: on the eve of the study, the skin of the inner surface of the patient's forearm is treated with a 5% alcohol solution of iodine. It is necessary to ask the patient about the tolerance of drugs, in particular, anesthetics (tetracaine, lidocaine, procaine), if necessary, conduct intradermal allergological tests. The medical history should reflect the date of the drug tolerance test, a detailed description of the patient's condition (presence or absence of signs of hypersensitivity); the signature of the nurse who observed the patient within 12 hours after the test is required.

2. Purification of the bronchial tree in the presence of purulent sputum: for 3-4 days, as prescribed by the doctor, the patient is prescribed bronchial drainage (by taking the appropriate, optimal for sputum discharge, position with the raised foot end of the bed), expectorants and bronchodilators.

3. Psychological preparation: the patient should be explained the purpose and necessity of the upcoming study. In some cases, patients before the study may develop insomnia, increase blood pressure. In this case, as prescribed by the doctor, the patient is given sedatives and antihypertensive drugs.

4. Direct preparation of the patient for the study: on the eve of the study, the patient is given a light dinner (exclude milk, cabbage, meat). It is necessary to warn the patient that the study is carried out on an empty stomach; On the morning of the study, he should also not drink water, medicines and smoke. The patient needs to be reminded that before the study, he must empty the bladder and intestines (naturally).

5. Premedication: 30-60 minutes before the examination, according to the doctor's prescription, the patient is given special preparations (diazepam, atropine, etc.) in order to create conditions for free access of the bronchoscope. Special attention should be given to the patient after the study, since the following complications may develop:

* the appearance or intensification of coughing with sputum with a large amount of radiopaque substance (sometimes the injected substance is released within 1-2 days); while the patient should be provided with a special jar (spittoon) for sputum;

* increased body temperature;

* the development of pneumonia (in rare cases, with poor contrast agent secretion).

If a patient develops symptoms after bronchography, such as fever, worsening of the general condition, a sharp increase in cough, the appearance of shortness of breath, the nurse should immediately inform the doctor about this.

Fluoroscopy and radiography are also often used to study the CCC (heart, aorta, pulmonary artery). X-ray examination allows you to determine the size of the heart and its chambers, large vessels, the presence of displacement of the heart and its mobility during contractions, the presence of fluid in the pericardial cavity. If necessary, the patient is offered to drink a small amount of a radiopaque substance (a suspension of barium sulfate), which makes it possible to contrast the esophagus and judge the degree of enlargement of the left atrium by the degree of its displacement. Special preparation of the patient is not required.

Contrast radiography (angiocardiography) is used to determine the condition of large vessels and chambers of the heart. A radiopaque substance is injected into the large vessels and cavities of the heart through special probes. This procedure is actually surgical operation, it is carried out in a specially equipped operating room, as a rule, in the conditions of a cardiac surgery department. On the eve of the study, the patient needs to conduct tests for the tolerance of iodine-containing drugs and anesthetics. The study is carried out on an empty stomach. In addition, the nurse should pay special attention to the patient after the study, since the introduction of a radiopaque substance into the heart cavity can cause not only early, but also late complications. X-ray examination of the digestive organs makes it possible to assess the state of hollow (esophagus, stomach, intestines, biliary tract) and parenchymal (liver, pancreas) organs. Radiography and fluoroscopy of the digestive organs without a radiopaque agent are used to detect intestinal obstruction or perforation of the stomach and intestines. The use of a radiopaque substance (suspension of barium sulfate) allows you to determine the motor function and relief of the mucous membrane of the digestive tract, the presence of ulcers, tumors, areas of narrowing or expansion of various sections of the digestive tract.

Examination of the esophagus. Preparation of the patient for x-ray examination of the esophagus depends on the indications.

* No special preparation is required to detect a foreign body in the esophagus.

* To assess the motor function of the esophagus and its contours (detection of areas of narrowing and expansion, tumors, etc.), fluoroscopy and / or serial radiography is performed; while the patient before the study is given to drink a radiopaque substance (150-200 ml of a suspension of barium sulfate).

* If necessary, carry out differential diagnosis organic narrowing and functional damage (spasm of the esophagus), 15 minutes before the study, as prescribed by the doctor, the patient is administered 1 ml of a 0.1% solution of atropine. In the presence of a pronounced organic narrowing of the esophagus, as prescribed by the doctor, using a thick probe and a rubber pear, the accumulated liquid is suctioned from the esophagus.

Examination of the stomach and duodenum. The preparation of the patient for an x-ray examination consists in the release of these sections of the digestive tract from food masses and gases and begins a few days before the examination. The stages of patient preparation are as follows.

1. Appointment 3 days before the study of a diet that excludes food rich in plant fiber and contains other substances that contribute to increased gas formation. It is necessary to exclude freshly baked rye bread, potatoes, legumes, milk, vegetables and fruits, fruit juices from the diet.

2. On the eve of the study, the patient is prescribed a light dinner (no later than 8 pm). Eggs, cream, caviar, cheese, meat and fish without seasonings, tea or coffee without sugar, porridge boiled in water are allowed.

3. The night before and in the morning 2 hours before the study, the patient is given a cleansing enema.

4. It is necessary to warn the patient that 12 hours before the study, he should stop eating, in the morning on the day of the study, he should also not drink, take any medicines and smoke.

Colon examination. To conduct an x-ray examination of the colon - irrigoscopy (lat. irrigatio - irrigation) - a complete cleaning of the intestine from contents and gases is necessary. A radiopaque substance - up to 1.5 liters of warm (36-37 ° C) suspension of barium sulfate - is injected into the intestine with an enema directly in the X-ray room. Contraindications to irrigoscopy: diseases of the rectum and its sphincters (inflammation, tumor, fistula, sphincter fissure). There are situations when the patient cannot keep the fluid injected into the intestines (rectal prolapse, sphincter weakness), which makes this procedure impossible.

Stages of preparing the patient for the study:

1. Appointment 2-3 days before the study of a diet that excludes food rich in plant fiber and contains other substances that contribute to increased gas formation. It is necessary to exclude fresh rye bread, potatoes, legumes, fresh milk, fresh vegetables and fruits, fruit juices from the diet.

2. On the eve of the study, the patient is prescribed a light dinner (no later than 8 pm). Allowed scrambled eggs, kefir, caviar, cheese, boiled meat and fish without seasoning, tea or coffee without sugar, semolina, boiled in water.

3. On the eve of the study, before dinner, the patient is given 30 g of castor oil for oral administration (a contraindication to taking castor oil is intestinal obstruction).

4. The night before (30-40 minutes after dinner), the patient is given cleansing enemas with an interval of 1 hour until “clean” washings are obtained.

5. In the morning, 2 hours before the study, the patient is given a cleansing enema, also until “clean” washings are obtained.

6. The study is carried out on an empty stomach. If necessary, according to the doctor's prescription, the patient is allowed a light protein breakfast in the morning (low-fat cottage cheese, whipped protein soufflé or protein omelet, boiled fish), which allows you to cause a reflex movement of the contents of the small intestine into the large intestine and prevent the accumulation of gases in the intestine. In this case, the morning cleansing enema is given 20-30 minutes after breakfast.

7. 30 minutes before the examination, the patient is given a gas outlet tube.

Oral lavage is another way to cleanse the intestines before X-ray and endoscopic examination. For its implementation, iso-osmotic solutions are used, for example, Fortrans. Fortrans package intended for one patient consists of four bags containing 64 g of polyethylene glycol in combination with 9 g of electrolytes - sodium sulfate, sodium bicarbonate, sodium chloride and potassium chloride. Each package is dissolved in 1 liter of boiled water. As a rule, the patient is prescribed the first 2 liters of solution in the afternoon on the day preceding the study; the second portion in the amount of 1.5-2 liters is given in the morning on the day of the study. The action of the drug (intestinal emptying) is not accompanied by pain and tenesmus, begins 50-80 minutes after the start of taking the solution and lasts for 2-6 hours. Bowel emptying with repeated administration of Fortrans in the morning begins 20-30 minutes after taking the drug. The use of Fortrans is contraindicated in patients with non-specific ulcerative colitis, Crohn's disease, intestinal obstruction, abdominal pain of unknown etiology.

X-ray examination of the gallbladder (cholecystography) allows you to determine its shape, position and deformation, the presence of stones in it, the degree of emptying. A radiopaque substance (for example, sodium iopodate - "Bilimin") is given to the patient to drink; while the concentration of the contrast agent reaches a maximum in the gallbladder 10-15 hours after its administration. If a radiopaque substance is administered intravenously, such a study is called intravenous cholegraphy. This method allows contrasting intrahepatic bile ducts. In this case, after 20-25 minutes, you can get an image of the bile ducts, and after 2-2.5 hours of the gallbladder. Preparation of the patient for the study depends on the method of administration of the contrast agent.

The stages of preparing the patient for cholecystography are as follows:

1. Appointment 2-3 days before the study of a diet that excludes food rich in plant fiber and contains other substances that contribute to increased gas formation. It is necessary to exclude from the diet fresh rye bread, potatoes, legumes, fresh milk, fresh vegetables and fruits, fruit juices.

2. On the eve of the study, after a light dinner (with the exception of fats), the patient is given a cleansing enema.

3. 12 hours before the study, the patient takes a radiopaque substance (for example, 3 g of "Bilimin"), drinking warm tea. If the patient is obese, the patient is given to drink "Bilimin" twice - for 3 g at 20 o'clock and at 22 o'clock.

4. It is necessary to warn the patient that the study is carried out on an empty stomach. Directly in the X-ray room, the patient receives a choleretic breakfast (100 g of sour cream or 20 g of butter on a thin piece of white bread).

With intravenous cholegraphy, the stages of preparing the patient for the study include a mandatory test for individual tolerability of the drug (several days before the study), the appointment of a diet with the exclusion of products that contribute to increased gas formation, the setting of cleansing enemas the night before and in the morning on the day of the study. Intravenous cholegraphy is also performed on an empty stomach. Before the study, a radiopaque substance warmed up to the temperature of the human body is injected intravenously slowly (within 4-5 minutes).

Plain radiography of the kidneys and urinary tract makes it possible to determine the shape and position of the renal pelvis and ureters, in some cases - to assess the presence of stones (calculi).

contrast radiography. Depending on the method of administration of the radiopaque substance, two types of contrast radiography of the kidneys and urinary tract are distinguished.

* Retrograde urography is a research method when a radiopaque substance is injected through a urinary catheter under the control of a cystoscope into the desired ureter. Special preparation of the patient is not required.

* With excretory urography, a radiopaque substance is administered intravenously. This research method allows you to identify the presence of stones, anomalies, cicatricial narrowing, tumor formations in the kidneys and urinary tract. The rate of release of the radiopaque substance characterizes the functional ability of the kidneys.

The stages of preparing a patient for an X-ray examination of the kidneys and urinary tract are as follows:

2. Carrying out a test for individual tolerance of a radiopaque substance 12-24 hours before the study.

3. Restriction of fluid intake by the patient 12-18 hours before the study.

4. Statement of a cleansing enema (until "clean" washings are obtained) the night before and in the morning 2 hours before the study. The study is carried out strictly on an empty stomach.

The radiopaque agent is administered to the patient directly in the radiology room.

The most important method for diagnosing tuberculosis at different stages of its formation is the X-ray method of investigation. Over time, it became clear that given infectious disease there is no “classic”, that is, a permanent x-ray picture. Any lung disease in the pictures may look like tuberculosis. Conversely, tuberculosis infection can be similar to many lung diseases on x-rays. It is clear that given fact makes differential diagnosis difficult. In this case, specialists resort to other, no less informative methods for diagnosing tuberculosis.

Although x-rays have disadvantages, this method sometimes plays a key role in the diagnosis of not only tuberculosis infection, but also other diseases of the chest. It accurately helps to determine the localization and extent of the pathology. Therefore, the described method most often becomes the right basis for making an accurate diagnosis - tuberculosis. For its simplicity and informativeness, chest X-ray examination is mandatory for the adult population in Russia.

How are x-rays taken?

The organs of our body have an unequal structure - bones and cartilage are dense formations, compared with parenchymal or abdominal organs. It is on the difference in the density of organs and structures that X-ray images are based. The rays that pass through the anatomical structures are absorbed differently. This directly depends on the chemical composition of the organs and the volume of the studied tissues. The strong absorption of X-ray radiation by the organ gives a shadow on the resulting image, if it is transferred to a film, or on a screen.

Sometimes it is necessary to additionally "mark" some structures that require more careful study. In this case, resort to contrast. In this case, special substances are used that can absorb rays in a larger or smaller volume.

The algorithm for obtaining a snapshot can be represented by the following points:

Radiation source - X-ray tube.
The object of the study is the patient, while the purpose of the study can be both diagnostic and prophylactic.
The receiver of the emitter is a cassette with a film (for radiography), fluoroscopic screens (for fluoroscopy).
Radiologist - who examines the image in detail and gives his opinion. It becomes the basis for the diagnosis.

Is x-ray dangerous for humans?

It has been proven that even tiny doses of X-rays can be dangerous for living organisms. Studies conducted on laboratory animals show that X-ray radiation caused disturbances in the structure of their chromosomes of germ cells. This phenomenon has a negative impact on the next generation. The cubs of the irradiated animals had congenital anomalies, extremely low resistance and other irreversible abnormalities.

An x-ray examination, which is carried out in full accordance with the rules of technique for its implementation, is absolutely safe for the patient.

It is important to know! In the case of using faulty equipment for X-ray examination or a gross violation of the algorithm for taking a picture, as well as the lack of personal protective equipment, harm to the body is possible.

Each x-ray examination involves the absorption of microdoses. Therefore, the health care provided for a special decree, which the medical staff undertakes to comply with when taking pictures. Among them:

The study is carried out according to strict indications for the patient.
Pregnant and pediatric patients are checked with extreme caution.
The use of the latest equipment that minimizes radiation exposure to the patient's body.
X-ray room PPE - protective clothing, protectors.
Reduced exposure time - which is important for both the patient and the medical staff.
Control of the received doses at medical personnel.

The most common methods in the X-ray diagnosis of tuberculosis

For the chest organs, the following methods are most often used:

X-ray - the use of this method involves translucence. This is the most budgetary and popular x-ray study. The essence of his work is to irradiate the chest area with X-rays, the image of which is projected onto a screen, followed by examination by a radiologist. The method has disadvantages - the resulting image is not printed. Therefore, in fact, it can be studied only once, which makes it difficult to diagnose small foci in tuberculosis and other diseases of the chest organs. The method is most often used to make a preliminary diagnosis;
Radiography is a picture that, unlike fluoroscopy, remains on the film, therefore it is mandatory in the diagnosis of tuberculosis. The picture is taken in a direct projection, if necessary - in a lateral one. The rays that have previously passed through the body are projected onto a film that is able to change its properties due to the silver bromide included in its composition - dark areas indicate that silver has recovered to a greater extent on them than on transparent ones. That is, the former display the "air" space of the chest or other anatomical region, and the latter - bones and cartilage, tumors, accumulated fluid;
Tomography - allows specialists to get a layered picture. At the same time, in addition to the X-ray machine, special devices are used that can register images of organs in their different parts without overlapping each other. The method is highly informative in determining the localization and size of the tuberculosis focus;
Fluorography - a picture is obtained by photographing an image from a fluorescent screen. It can be large- or small-frame, electronic. It is used for mass preventive examination for the presence of tuberculosis and lung cancer.

Other X-ray methods and preparation for them

Some patient conditions require imaging of other anatomical regions. In addition to the lungs, you can take an x-ray of the kidneys and gallbladder, the gastrointestinal tract or the stomach itself, blood vessels and other organs:

X-ray of the stomach - which will allow you to diagnose an ulcer or neoplasms, developmental anomalies. It should be noted that the procedure has contraindications in the form of bleeding and other acute conditions. Before the procedure, it is necessary to follow a diet three days before the procedure and a cleansing enema. Manipulation is carried out using barium sulfate, which fills the stomach cavity.
X-ray study Bladder- or cystography - a method that is widely used in urology and surgery to detect kidney pathology. Since with a high degree accuracy can show stones, tumors, inflammations and other pathologies. In this case, the contrast is injected through a catheter previously installed in the patient's urethra. For children, manipulation is performed under anesthesia.
X-ray of the gallbladder - cholecystography - which is also performed using a contrast agent - bilitrast. Preparation for the study - a diet with a minimum fat content, taking iopanoic acid before bedtime, before the procedure itself, it is recommended to conduct a test for sensitivity to contrast and a cleansing enema.

X-ray examination in children

Smaller patients can also be referred for x-rays, and even the neonatal period is not a contraindication for this. An important point for taking a picture there is a medical justification, which must be documented either in the child's card or in his medical history.

For older children - after 12 years - an X-ray examination is no different from an adult. Young children and a newborn are examined on x-rays using special techniques. There are specialized X-ray rooms in children's hospitals, where even premature babies can be examined. In addition, the technique of taking pictures is strictly observed in such offices. Any manipulations there are carried out strictly observing the rules of asepsis and antisepsis.

In the case when an image needs to be taken for a child under 14 years old, three persons are involved - a radiologist, an X-ray technician and a nurse accompanying a small patient. The latter is needed to help fix the child and to provide care and observation before and after the procedure.

For babies in X-ray rooms, special fixing devices are used and, of course, means for protection against radiation in the form of diaphragms or tubes. Particular attention is paid to the gonads of the child. In this case, electron-optical amplifiers are used and the radiation exposure is reduced to a minimum.

It is important to know! Most often, radiography is used for pediatric patients due to its low ionizing load compared to other methods of X-ray examination.

X-ray methods studies are based on the ability of x-rays to penetrate organs and tissues human body.

Fluoroscopy- the method of transillumination, examination of the organ under study behind a special x-ray screen.

Radiography- a method of obtaining images, it is necessary to document the diagnosis of the disease, to monitor the observation of the functional state of the patient.

Dense fabrics delay the rays to varying degrees. Bone and parenchymal tissues are capable of retaining x-rays, and therefore do not require special patient preparation. To obtain more reliable data on the internal structure of the organ, the contrast method of research is used, which determines the "visibility" of these organs. The method is based on the introduction of special substances into the organs that delay x-rays.

As contrast agents in X-ray examination of the gastrointestinal tract (stomach and duodenum, intestines), a suspension of barium sulfate is used; in fluoroscopy of the kidneys and urinary tract, gallbladder and biliary tract, iodine contrast preparations are used.

Iodine-containing contrast agents are often administered intravenously. 1-2 days before the study, the nurse should test the patient's tolerance to the contrast agent. To do this, 1 ml of a contrast agent is injected very slowly intravenously and the patient's reaction is observed during the day. With the appearance of itching, runny nose, urticaria, tachycardia, weakness, lowering blood pressure, the use of radiopaque substances is contraindicated!

Fluorography- large-frame photography from the X-ray screen on a small film. The method is used for mass survey of the population.

Tomography- obtaining images of individual layers of the studied area: lungs, kidneys, brain, bones. Computed tomography is used to obtain layered images of the tissue under study.

Chest X-ray

Research objectives:

1. Diagnosis of diseases of the chest organs (inflammatory, neoplastic, and systemic diseases, heart defects and large vessels, lung, pleura.).

2. Control of the treatment of the disease.

Training objectives:

Preparation:

5. Find out if the patient can stand for the time necessary for the study and hold his breath.

6.Determine the method of transportation.

7. The patient must have a referral, outpatient card or medical history with him. If you have previously had lung studies, take the results (images).

8. The study is performed on a patient naked to the waist (a light T-shirt without radiopaque fasteners is possible).

Fluoroscopy and radiography of the esophagus, stomach and duodenum

Purpose of the study - assessment of radioanatomy and function of the esophagus, stomach and duodenum:

Identification of structural features, malformations, attitudes towards surrounding tissues;

Determination of violations of the motor function of these organs;

Identification of submucosal and infiltrating tumors.

Training objectives:

1. Ensure the possibility of conducting a study.

2. Get reliable results.

Preparation:

1. Explain to the patient the essence of the study and the rules for preparing for it.

2. Obtain the consent of the patient for the upcoming study.

3.Inform the patient about the exact time and place of the study.

4. Ask the patient to repeat the preparation for the study, especially on an outpatient basis.

5. For 2-3 days before the study, foods that cause flatulence (gas formation) are excluded from the patient's diet: rye bread, raw vegetables, fruits, milk, legumes, etc.

6. Dinner the night before must be no later than 19.00

7. On the evening before and in the morning no later than 2 hours before the examination, the patient is given a cleansing enema.

8. The study is carried out on an empty stomach, no need to drink, smoke, take medication.

9. When examining with contrast agent(barium for x-ray studies) to find out an allergic history; ability to absorb contrast.

10. Remove removable dentures.

11. The patient must have with him: a referral, an outpatient card / medical history, data from previous studies of these organs, if any.

12. Get rid of tight clothing and clothing that has radiopaque fasteners.

Note. Salt laxative instead of an enema should not be given, as it increases gas formation.

Breakfast is served to the patient in the ward.

The medical history after the study is returned to the department.

Possible Patient Problems

Real:

1. The appearance of discomfort, pain during examination and / or preparation for it.

2. Inability to swallow barium due to impaired swallowing reflex.

Potential:

1. The risk of developing pain due to spasms of the esophagus and stomach caused by the procedure itself (especially in the elderly) and when the stomach is distended.

2. Risk of vomiting.

3. The risk of developing an allergic reaction.

X-ray examination of the large intestine (irrigoscopy)

An x-ray examination of the large intestine is performed after the introduction of a barium suspension into the large intestine using an enema.

Research objectives:

1. determination of the shape, position, condition of the mucous membrane, tone and peristalsis of various sections of the colon.

2. Identification of malformations and pathological changes (polyps, tumors, diverticula, intestinal obstruction).

Training objectives:

1. Ensure the possibility of conducting a study.

2. Get reliable results.

Preparation:

1. Explain to the patient the essence of the study and the rules for preparing for it.

2. Obtain the consent of the patient for the upcoming study.

3.Inform the patient about the exact time and place of the study.

4. Ask the patient to repeat the preparation for the study, especially on an outpatient basis.

5.For three days before the study, a slag-free diet (see the composition of the diet in the appendix).

6 As prescribed by the doctor - taking enzymes and activated charcoal for three days before the study, chamomile infusion 1/3 cup three times a day.

7.the day before studies the last meal at 14 - 15 hours.

At the same time, fluid intake is not limited (you can drink broth, jelly, compote, and so on). Avoid dairy products!

8. On the day before the study, taking laxatives - orally or rectally.

9. At 22:00 you need to make two cleansing enemas of 1.5 - 2 liters. If, after the second enema, the wash water is colored, then make another enema. The water temperature should not be higher than 20 - 22 0 C (room temperature, when pouring, the water should feel cool).

10. In the morning on the day of the study you need to do two more enemas 3 hours before irrigoscopy (in the presence of dirty washings, repeat the enemas, achieving clean washings).

11. The patient must have with him: a referral, an outpatient card / medical history, data from a previous colonoscopy, barium enema, if performed.

12. Patients over 30 years of age should carry an ECG no more than a week old.

13. If the patient cannot go without food for so long (diabetics and so on), then in the morning, on the day of the study, you can eat a piece of meat or another high-protein breakfast.

Possible Patient Problems

Real:

1. Inability to diet.

2. Inability to take a certain position.

3. Insufficient preparation due to many days of constipation, non-compliance temperature regime water in the enema, the volume of water and the number of enemas.

Potential:

1. The risk of pain due to intestinal spasm caused by the procedure itself and / or preparation for it.

2.Risk violation of cardiac activity and respiration.

3. The risk of obtaining unreliable results with insufficient preparation, the impossibility of introducing a contrast enema.

Preparation option without enemas

The method is based on the effect of an osmotically active substance on the motility of the colon and the excretion of feces along with the drunk solution.

Procedure sequence:

1. Dissolve one packet of Fortrans in one liter of boiled water.

2. During this examination, for complete cleansing of the intestines, it is necessary to take 3 liters of an aqueous solution of the Fortrans preparation.

3. If the examination is carried out in the morning, then the prepared Fortrans solution is taken on the eve of the examination, 1 glass every 15 minutes (1 liter per hour) from 16:00 to 19:00. The effect of the drug on the intestines lasts up to 21 hours.

4. On the eve of the evening until 18:00, you can take a light dinner. Liquid is not limited.

Oral cholecystography

The study of the gallbladder and biliary tract is based on the ability of the liver to capture and accumulate iodine-containing contrast agents, and then excrete them with bile through the gallbladder and biliary tract. This allows you to get an image of the biliary tract. On the day of the examination in the X-ray room, the patient is given a choleretic breakfast, after 30-45 minutes a series of images are taken

Research objectives:

1. Assessment of the location and functions of the gallbladder and extrahepatic bile ducts.

2. Identification of malformations and pathological changes (presence of gallstones, tumors)

Training objectives:

1. Ensure the possibility of conducting a study.

2. Get reliable results.

Preparation:

1. Explain to the patient the essence of the study and the rules for preparing for it.

2. Obtain the consent of the patient for the upcoming study.

3.Inform the patient about the exact time and place of the study.

4. Ask the patient to repeat the preparation for the study, especially on an outpatient basis.

5. Find out if you are allergic to the contrast agent.

The day before:

6. When examining, pay attention to the skin and mucous membranes, in case of jaundice - tell the doctor.

7. Compliance with a slag-free diet for three days before the study

8. As prescribed by the doctor - taking enzymes and activated charcoal for three days before the study.

9. The night before - a light dinner no later than 19:00.

10. 12 hours before the study - taking a contrast agent orally for 1 hour at regular intervals, drinking sweet tea. (contrast agent is calculated on the patient's body weight). The maximum concentration of the drug in the gallbladder is 15-17 hours after its administration.

11. The night before and 2 hours before the study, the patient is given a cleansing enema

On the day of the study:

12. In the morning, come to the X-ray room on an empty stomach; You can not take medicine, smoke.

13. Bring 2 raw eggs or 200 g of sour cream and breakfast (tea, sandwich).

14. The patient must have with him: a referral, an outpatient card / medical history, data from previous studies of these organs, if any.

Possible Patient Problems

Real:

1. The impossibility of carrying out the procedure due to the appearance of jaundice (direct bilirubin absorbs the contrast agent).

Potential:

risk of an allergic reaction.

2. The risk of developing biliary colic when taking choleretic drugs (sour cream, egg yolks).

Radiology as a science dates back to November 8, 1895, when the German physicist Professor Wilhelm Conrad Roentgen discovered rays, later named after him. Roentgen himself called them X-rays. This name has been preserved in his homeland and in Western countries.

Basic properties of X-rays:

X-rays, proceeding from the focus of the X-ray tube, propagate in a straight line.

They do not deviate in an electromagnetic field.

Their propagation speed is equal to the speed of light.

X-rays are invisible, but when absorbed by certain substances, they cause them to glow. This glow is called fluorescence and is the basis of fluoroscopy.

X-rays have a photochemical effect. This property of X-rays is the basis of radiography (the currently generally accepted method for producing X-ray images).

X-ray radiation has an ionizing effect and gives the air the ability to conduct electricity. Neither visible, nor thermal, nor radio waves can cause this phenomenon. Based on this property, X-ray radiation, like radio radiation, active substances is called ionizing radiation.

An important property of X-rays is their penetrating power, i.e. the ability to pass through the body and objects. The penetrating power of X-rays depends on:

From the quality of the rays. The shorter the length of the X-rays (i.e., the harder the X-rays), the deeper these rays penetrate and, conversely, the longer the wavelength of the rays (the softer the radiation), the shallower they penetrate.

From the volume of the body under study: the thicker the object, the more difficult it is for X-rays to “penetrate” it. The penetrating power of X-rays depends on the chemical composition and structure of the body under study. The more atoms of elements with high atomic weight and serial number (according to the periodic table) in a substance exposed to X-rays, the stronger it absorbs X-rays and, conversely, the lower the atomic weight, the more transparent the substance for these rays. The explanation for this phenomenon is that electromagnetic radiation with a very short wavelength, which are X-rays, a lot of energy is concentrated.

X-rays have an active biological effect. In this case, DNA and cell membranes are critical structures.

One more circumstance must be taken into account. X-rays obey the inverse square law, i.e. The intensity of X-rays is inversely proportional to the square of the distance.

Gamma rays have the same properties, but these types of radiation differ in the way they are produced: X-rays are obtained in high-voltage electrical installations, and gamma radiation is due to the decay of atomic nuclei.

Methods of X-ray examination are divided into basic and special, private.

Basic X-ray methods: radiography, fluoroscopy, computed x-ray tomography.

Radiography and fluoroscopy are performed on x-ray machines. Their main elements are a feeder, an emitter (X-ray tube), devices for the formation of X-rays and radiation receivers. X-ray machine

powered by the city's AC network. The power supply increases the voltage to 40-150 kV and reduces the ripple, in some devices the current is almost constant. The quality of X-ray radiation, in particular, its penetrating power, depends on the magnitude of the voltage. As the voltage increases, the radiation energy increases. This reduces the wavelength and increases the penetrating power of the resulting radiation.

An X-ray tube is an electrovacuum device that converts electrical energy into X-ray energy. An important element of the tube are the cathode and anode.

When a low voltage current is applied to the cathode, the filament heats up and begins to emit free electrons (electron emission), forming an electron cloud around the filament. When the high voltage is turned on, the electrons emitted by the cathode are accelerated in the electric field between the cathode and the anode, fly from the cathode to the anode and, hitting the anode surface, are decelerated, releasing X-ray quanta. Screening gratings are used to reduce the effect of scattered radiation on the information content of radiographs.

X-ray receivers are X-ray film, fluorescent screen, digital radiography systems, and in CT, dosimetric detectors.

Radiography- X-ray examination, in which an image of the object under study is obtained, fixed on a photosensitive material. When taking X-rays, the object to be photographed must be in close contact with the cassette loaded with film. X-ray radiation coming out of the tube is directed perpendicularly to the center of the film through the middle of the object (the distance between the focus and the patient's skin under normal operating conditions is 60-100 cm). Indispensable equipment for radiography are cassettes with intensifying screens, screening grids and a special x-ray film. Special movable gratings are used to filter out soft x-rays that can reach the film, as well as secondary radiation. The cassettes are made of opaque material and correspond in size to the standard dimensions of the produced x-ray film(13 × 18 cm, 18 × 24 cm, 24 × 30 cm, 30 × 40 cm, etc.).

X-ray film is usually coated on both sides with a photographic emulsion. The emulsion contains silver bromide crystals that are ionized by x-ray and visible light photons. The X-ray film is in an opaque cassette along with X-ray intensifying screens (REI). REU is a flat base on which a layer of X-ray phosphor is applied. X-ray film is affected by X-rays not only by X-rays, but also by light from the REU. Intensifying screens are designed to increase the light effect of x-rays on photographic film. Currently, screens with phosphors activated by rare earth elements are widely used: lanthanum oxide bromide and gadolinium oxide sulfite. good ratio useful action rare-earth phosphor contributes to the high light sensitivity of screens and provides high image quality. There are also special screens - Gradual, which can even out the existing differences in the thickness and (or) density of the subject. The use of intensifying screens significantly reduces the exposure time for radiography.

The blackening of the x-ray film occurs due to the reduction of metallic silver under the action of x-rays and light in its emulsion layer. The number of silver ions depends on the number of photons acting on the film: the greater their number, the greater the number of silver ions. The changing density of silver ions forms an image hidden inside the emulsion, which becomes visible after special processing by the developer. Processing of the filmed films is carried out in a photo laboratory. The processing process is reduced to developing, fixing, washing the film, followed by drying. During the development of the film, black metallic silver is deposited. Non-ionized silver bromide crystals remain unchanged and invisible. The fixer removes the silver bromide crystals, leaving metallic silver. After fixing, the film is insensitive to light. Drying of films is carried out in drying cabinets, which takes at least 15 minutes, or occurs naturally, while the picture is ready the next day. When using processing machines, images are obtained immediately after the study. The image on x-ray film is due to varying degrees of blackening caused by changes in the density of the black silver granules. The darkest areas on x-ray film correspond to the highest radiation intensity, so the image is called negative. White (light) areas on radiographs are called dark (blackouts), and black areas are light (enlightenment) (Fig. 1.2).

Benefits of radiography:

An important advantage of radiography is its high spatial resolution. According to this indicator, no visualization method can be compared with it.

The dose of ionizing radiation is lower than with fluoroscopy and x-ray computed tomography.

Radiography can be performed both in the X-ray room, and directly in the operating room, dressing room, plastering room, or even in the ward (using mobile X-ray units).

An x-ray is a document that can be stored for a long time. It can be studied by many experts.

Disadvantage of radiography: the study is static, there is no possibility of assessing the movement of objects during the study.

Digital radiography includes ray pattern detection, image processing and recording, image presentation and viewing, information storage. In digital radiography, analog information is converted into digital form using analog-to-digital converters, the reverse process occurs using digital-to-analog converters. To display an image, a digital matrix (numerical rows and columns) is transformed into a matrix of visible image elements - pixels. A pixel is the smallest element of a picture reproduced by an imaging system. Each pixel, in accordance with the value of the digital matrix, is assigned one of the shades of the gray scale. The number of possible gray scale shades between black and white is often specified on a binary basis, eg 10 bits = 2 10 or 1024 shades.

Currently, four digital radiography systems have been technically implemented and have already received clinical use:

− digital radiography from the screen of the electron-optical converter (EOC);

− digital fluorescent radiography;

− scanning digital radiography;

− digital selenium radiography.

The system of digital radiography from the image intensifier tube consists of an image intensifier tube, a television path and an analog-to-digital converter. The image intensifier tube is used as an image detector. The television camera converts the optical image on the image intensifier tube into an analog video signal, which is then formed into a digital data set using an analog-to-digital converter and transferred to a storage device. Then the computer translates this data into a visible image on the monitor screen. The image is studied on the monitor and can be printed on film.

In digital fluorescent radiography, after exposure to X-rays, luminescent memory plates are scanned by a special laser device, and the light beam that occurs during laser scanning is transformed into a digital signal that reproduces an image on a monitor screen that can be printed. Luminescent plates are built into cassettes that are reusable (from 10,000 to 35,000 times) with any X-ray machine.

In scanning digital radiography, a moving narrow beam of X-ray radiation is sequentially passed through all departments of the object under study, which is then recorded by a detector and, after digitization in an analog-to-digital converter, is transmitted to a computer monitor screen with a possible subsequent printout.

Digital selenium radiography uses a selenium-coated detector as an X-ray receiver. The latent image formed in the selenium layer after exposure in the form of areas with different electric charges is read using scanning electrodes and transformed into a digital form. Further, the image can be viewed on the monitor screen or printed on film.

Benefits of digital radiography:

reduction of dose loads on patients and medical personnel;

cost-effectiveness in operation (during shooting, an image is immediately obtained, there is no need to use x-ray film, other consumables);

high performance (about 120 images per hour);

digital image processing improves the quality of the image and thereby increases the diagnostic information content of digital radiography;

cheap digital archiving;

fast search of the x-ray image in computer memory;

reproduction of the image without loss of its quality;

the possibility of combining various equipment of the radiology department into a single network;

the ability to integrate into the general local network of the institution (" electronic history disease");

the possibility of organizing remote consultations (“telemedicine”).

Image quality when using digital systems can be characterized, as with other ray methods, by such physical parameters as spatial resolution and contrast. Shadow contrast is the difference in optical density between adjacent areas of the image. Spatial resolution is the minimum distance between two objects at which they can still be separated from one another in an image. Digitization and image processing lead to additional diagnostic possibilities. Thus, a significant distinguishing feature of digital radiography is a greater dynamic range. That is, x-rays with a digital detector will good quality over a larger range of x-ray doses than conventional x-rays. The ability to freely adjust image contrast in digital processing is also a significant difference between conventional and digital radiography. Contrast transfer is thus not limited by the choice of image receiver and exam parameters, and can be further adapted to solve diagnostic problems.

Fluoroscopy- transillumination of organs and systems using X-rays. Fluoroscopy is an anatomical and functional method that provides an opportunity to study the normal and pathological processes of organs and systems, as well as tissues by the shadow pattern of a fluorescent screen. The study is performed in real time, i.e. the production of the image and its acquisition by the researcher coincide in time. On fluoroscopy, a positive image is obtained. Light areas visible on the screen are called light, and dark areas are called dark.

Benefits of fluoroscopy:

allows you to examine patients in various projections and positions, due to which you can choose a position in which a pathological formation is better detected;

the possibility of studying the functional state of a number of internal organs: lungs, at various phases of respiration; pulsation of the heart with large vessels, motor function of the digestive canal;

close contact between the radiologist and the patient, which makes it possible to supplement the X-ray examination with the clinical one (palpation under visual control, targeted history), etc.;

the possibility of performing manipulations (biopsies, catheterizations, etc.) under the control of an x-ray image.

Flaws:

relatively large radiation exposure to the patient and attendants;

small throughput during the doctor's working hours;

limited capabilities of the researcher's eye in identifying small shadow formations and fine tissue structures; Indications for fluoroscopy are limited.

Electron-optical amplification (EOA). It is based on the principle of converting an X-ray image into an electronic image, followed by its transformation into an enhanced light image. An X-ray image intensifier tube is a vacuum tube (Fig. 1.3). X-rays carrying the image from the translucent object fall on the input fluorescent screen, where their energy is converted into light energy of the input luminescent screen. Next, the photons emitted by the luminescent screen fall on the photocathode, which converts light radiation into a stream of electrons. Under the influence of a constant high-voltage electric field (up to 25 kV) and as a result of focusing by electrodes and an anode of a special shape, the energy of electrons increases several thousand times and they are directed to the output luminescent screen. The brightness of the output screen is amplified up to 7,000 times compared to the input screen. The image from the output fluorescent screen is transmitted to the display screen by means of a television tube. The use of an EOS makes it possible to distinguish details with a size of 0.5 mm, i.e. 5 times smaller than with conventional fluoroscopic examination. When using this method, X-ray cinematography can be used, i.e. recording an image on film or videotape and digitizing the image using an analog-to-digital converter.

Rice. 1.3. EOP scheme. 1 − x-ray tube; 2 - object; 3 - input luminescent screen; 4 - focusing electrodes; 5 - anode; 6 − output luminescent screen; 7 - outer shell. The dotted lines indicate the electron flow.

X-ray computed tomography (CT). The creation of X-ray computed tomography was the most important event in radiation diagnostics. Evidence of this is the award of the Nobel Prize in 1979 to the famous scientists Cormac (USA) and Hounsfield (England) for the creation and clinical testing of CT.

CT allows you to study the position, shape, size and structure of various organs, as well as their relationship with other organs and tissues. Advances achieved with the help of CT in the diagnosis of various diseases served as a stimulus for the rapid technical improvement of devices and a significant increase in their models.

CT is based on the registration of X-ray radiation with sensitive dosimetric detectors and the creation of an X-ray image of organs and tissues using a computer. The principle of the method is that after the beams pass through the patient's body, they do not fall on the screen, but on the detectors, in which electrical impulses arise, which are transmitted after amplification to the computer, where, according to a special algorithm, they are reconstructed and create an image of the object studied on the monitor ( Fig. 1.4).

The image of organs and tissues on CT, unlike traditional x-rays, is obtained in the form of transverse sections (axial scans). On the basis of axial scans, an image reconstruction is obtained in other planes.

Three types of computed tomography scanners are currently used in radiology practice: conventional step, spiral or screw, multislice.

In conventional stepping CT scanners, high voltage is supplied to the X-ray tube through high-voltage cables. Because of this, the tube cannot rotate continuously, but must perform a rocking motion: one turn clockwise, stop, one turn counterclockwise, stop and back. As a result of each rotation, one image with a thickness of 1 - 10 mm is obtained in 1 - 5 seconds. In the interval between slices, the tomograph table with the patient moves to a set distance of 2–10 mm, and the measurements are repeated. With a slice thickness of 1 - 2 mm, stepping devices allow you to perform research in the "high resolution" mode. But these devices have a number of disadvantages. Scan times are relatively long and motion and breath artifacts may appear on images. Image reconstruction in projections other than axial ones is difficult or simply impossible. There are serious limitations when performing dynamic scanning and studies with contrast enhancement. In addition, small formations between sections may not be detected if the patient's breathing is uneven.

In spiral (screw) computed tomographs, the constant rotation of the tube is combined with the simultaneous movement of the patient table. Thus, during the study, information is obtained immediately from the entire volume of tissues under study (the entire head, chest), and not from individual sections. With spiral CT, a three-dimensional image reconstruction (3D mode) with high spatial resolution is possible, including virtual endoscopy, which allows visualizing the inner surface of the bronchi, stomach, colon, larynx, paranasal sinuses. Unlike endoscopy with fiber optics, the narrowing of the lumen of the object under study is not an obstacle to virtual endoscopy. But in the conditions of the latter, the color of the mucous membrane differs from the natural one and it is impossible to perform a biopsy (Fig. 1.5).

Stepping and spiral tomographs use one or two rows of detectors. Multislice (multi-detector) CT scanners are equipped with 4, 8, 16, 32 and even 128 rows of detectors. In multislice devices, the scan time is significantly reduced and the spatial resolution in the axial direction is improved. They can obtain information using a high-resolution technique. The quality of multiplanar and volumetric reconstructions is significantly improved. CT has a number of advantages over conventional X-ray examination:

First of all, high sensitivity, which makes it possible to differentiate individual organs and tissues from each other in terms of density up to 0.5%; on conventional radiographs, this figure is 10-20%.

CT makes it possible to obtain an image of organs and pathological foci only in the plane of the examined section, which gives a clear image without layering of formations lying above and below.

CT makes it possible to obtain accurate quantitative information about the size and density of individual organs, tissues and pathological formations.

CT makes it possible to judge not only the state of the organ under study, but also the relationship of the pathological process with surrounding organs and tissues, for example, tumor invasion into neighboring organs, the presence of other pathological changes.

CT allows you to get topograms, i.e. a longitudinal image of the area under study, like an x-ray, by moving the patient along a fixed tube. Topograms are used to establish the extent of the pathological focus and determine the number of sections.

With helical CT under 3D reconstruction, virtual endoscopy can be performed.

CT is indispensable for radiotherapy planning (radiation mapping and dose calculation).

CT data can be used for diagnostic puncture, which can be successfully used not only to detect pathological changes, but also to assess the effectiveness of treatment and, in particular, antitumor therapy, as well as to determine relapses and associated complications.

Diagnosis by CT is based on direct radiographic features, i.e. determining the exact localization, shape, size of individual organs and the pathological focus and, most importantly, on indicators of density or absorption. The absorbance index is based on the degree to which an X-ray beam is absorbed or attenuated as it passes through the human body. Each tissue, depending on the density of the atomic mass, absorbs radiation differently, therefore, at present, for each tissue and organ, an absorption coefficient (KA) is normally developed, denoted in Hounsfield units (HU). HUwater is taken as 0; bones with the highest density - for +1000, air, which has the lowest density - for - 1000.

With CT, the entire gray scale range, in which the image of tomograms on the video monitor screen is presented, is from - 1024 (black level) to + 1024 HU (white level). Thus, with a CT "window", that is, the range of changes in HU (Hounsfield units) is measured from - 1024 to + 1024 HU. For visual analysis of information in the gray scale, it is necessary to limit the "window" of the scale according to the image of tissues with similar density values. By successively changing the size of the "window", it is possible to study different density areas of the object under optimal visualization conditions. For example, for optimal lung evaluation, a black level is chosen close to the average lung density (between -600 and -900 HU). By a “window” with a width of 800 with a level of -600 HU, it is meant that densities - 1000 HU are seen as black, and all densities - 200 HU and above - as white. If the same image is used to assess the details of the bony structures of the chest, a 1000 wide window at +500 HU will produce a full gray scale between 0 and +1000 HU. The image during CT is studied on the monitor screen, placed in the long-term memory of the computer or obtained on a solid carrier - photographic film. Light areas on a CT scan (when viewed in black and white) are called “hyperdense”, and dark areas are called “hypodense”. Density means the density of the structure under study (Fig. 1.6).

The minimum size of a tumor or other pathological focus, determined by CT, ranges from 0.5 to 1 cm, provided that the HU of the affected tissue differs from that of the healthy one by 10-15 units.

The disadvantage of CT is the increased radiation exposure to patients. Currently, CT accounts for 40% of the total radiation dose received by patients during radiological procedures, while CT examinations account for only 4% of all radiological examinations.

In both CT and X-ray examinations, it becomes necessary to use the “image enhancement” technique to increase the resolution. Contrast in CT is performed with water-soluble radiopaque agents.

The “enhancement” technique is carried out by perfusion or infusion administration of a contrast agent.

X-ray examination methods are called special if artificial contrast is used. The organs and tissues of the human body become visible if they absorb x-rays to varying degrees. Under physiological conditions, such differentiation is possible only in the presence of natural contrast, which is determined by the difference in density ( chemical composition of these organs), size, position. The bone structure is well detected against the background of soft tissues, the heart and large vessels against the background of airy lung tissue, however, under conditions of natural contrast, the chambers of the heart cannot be distinguished separately, as, for example, the organs of the abdominal cavity. The need to study organs and systems with the same density by X-rays led to the creation of a technique for artificial contrasting. The essence of this technique is the introduction of artificial contrast agents into the organ under study, i.e. substances having a density that differs from the density of the organ and its environment (Fig. 1.7).

Radiocontrast media (RCS) It is customary to subdivide into substances with a high atomic weight (X-ray positive contrast agents) and low (X-ray negative contrast agents). The contrast agents must be harmless.

Contrast agents that absorb intensely x-rays (positive radiopaque agents) are:

Suspensions of salts of heavy metals - barium sulfate, used to study the gastrointestinal tract (it is not absorbed and excreted through natural routes).

Aqueous solutions organic compounds iodine - urographin, verografin, bilignost, angiographin, etc., which are introduced into the vascular bed, enter all organs with the blood flow and give, in addition to contrasting the vascular bed, contrasting other systems - urinary, gallbladder, etc.

Oily solutions of organic iodine compounds - yodolipol, etc., which are injected into fistulas and lymphatic vessels.

Non-ionic water-soluble iodine-containing radiocontrast agents: ultravist, omnipak, imagopak, vizipak are characterized by the absence of ionic groups in the chemical structure, low osmolarity, which significantly reduces the possibility of pathophysiological reactions, and thereby causes a low number of side effects. Non-ionic iodine-containing radiopaque agents cause a lower number of side effects than ionic high-osmolar contrast media.

X-ray negative, or negative contrast agents - air, gases "do not absorb" x-rays and therefore shade well the organs and tissues under study, which have a high density.

Artificial contrasting according to the method of administration of contrast agents is divided into:

The introduction of contrast agents into the cavity of the organs under study (the largest group). This includes studies of the gastrointestinal tract, bronchography, fistula studies, all types of angiography.

The introduction of contrast agents around the studied organs - retropneumoperitoneum, pneumothorax, pneumomediastinography.

The introduction of contrast agents into the cavity and around the studied organs. This group includes parietography. Parietography in diseases of the gastrointestinal tract consists in obtaining images of the wall of the investigated hollow organ after the introduction of gas, first around the organ, and then into the cavity of this organ.

A method based on the specific ability of some organs to concentrate individual contrast agents and at the same time shade them against the background of surrounding tissues. These include excretory urography, cholecystography.

Side effects of RCS. Body reactions to the introduction of RCS are observed in approximately 10% of cases. By nature and severity, they are divided into 3 groups:

Complications associated with the manifestation toxic action on various organs with functional and morphological lesions.

The neurovascular reaction is accompanied by subjective sensations (nausea, feeling of heat, general weakness). Objective symptoms in this case are vomiting, lowering blood pressure.

Individual intolerance to RCS with characteristic symptoms:

From the side of the central nervous system - headaches, dizziness, agitation, anxiety, fear, the occurrence of convulsive seizures, cerebral edema.
Skin reactions - hives, eczema, itching, etc.
Symptoms associated with impaired activity of the cardiovascular system - pallor skin, discomfort in the region of the heart, drop in blood pressure, paroxysmal tachycardia or bradycardia, collapse.
Symptoms associated with respiratory failure - tachypnea, dyspnea, asthma attack, laryngeal edema, pulmonary edema.

RCS intolerance reactions are sometimes irreversible and fatal.

The mechanisms of development of systemic reactions in all cases are similar in nature and are due to the activation of the complement system under the influence of RCS, the effect of RCS on the blood coagulation system, the release of histamine and other biologically active substances, a true immune response, or a combination of these processes.

In mild cases of adverse reactions, it is enough to stop the injection of RCS and all phenomena, as a rule, disappear without therapy.

With the development of severe adverse reactions, primary emergency care should begin at the place of production of the study by employees of the x-ray room. First of all, it is necessary to immediately stop the intravenous administration of the radiopaque agent, call a doctor whose duties include providing emergency medical care, establish reliable access to the venous system, ensure airway patency, for which you need to turn the patient’s head to the side and fix the tongue, and also ensure the possibility of carrying out (if necessary) inhalation of oxygen at a rate of 5 l / min. When anaphylactic symptoms appear, the following urgent anti-shock measures should be taken:

- inject intramuscularly 0.5-1.0 ml of a 0.1% solution of adrenaline hydrochloride;

- in the absence of a clinical effect with preservation of severe hypotension (below 70 mm Hg), start intravenous infusion at a rate of 10 ml / h (15-20 drops per minute) of a mixture of 5 ml of a 0.1% solution of adrenaline hydrochloride diluted in 400 ml of 0.9% sodium chloride solution. If necessary, the infusion rate can be increased to 85 ml / h;

- in a serious condition of the patient, additionally intravenously introduce one of the glucocorticoid preparations (methylprednisolone 150 mg, dexamethasone 8-20 mg, hydrocortisone hemisuccinate 200-400 mg) and one of the antihistamines (diphenhydramine 1% -2.0 ml, suprastin 2% -2 .0 ml, tavegil 0.1% -2.0 ml). The introduction of pipolfen (diprazine) is contraindicated due to the possibility of developing hypotension;

- in case of adrenaline-resistant bronchospasm and an attack of bronchial asthma, slowly inject 10.0 ml of a 2.4% solution of aminophylline intravenously. If there is no effect, re-introduce the same dose of aminophylline.

In case of clinical death, carry out mouth-to-mouth artificial respiration and chest compressions.

All anti-shock measures should be carried out as quickly as possible until the blood pressure normalizes and the patient's consciousness is restored.

With the development of moderate vasoactive adverse reactions without significant respiratory and circulatory disorders, as well as with skin manifestations, emergency care may be limited to the introduction of only antihistamines and glucocorticoids.

In case of laryngeal edema, along with these drugs, 0.5 ml of a 0.1% solution of adrenaline and 40-80 mg of lasix should be administered intravenously, as well as humidified oxygen inhalation. After the implementation of mandatory anti-shock therapy, regardless of the severity of the condition, the patient should be hospitalized to continue intensive care and rehabilitation treatment.

Due to the possibility of developing adverse reactions, all radiological rooms in which intravascular X-ray contrast studies are performed must have the tools, devices and medicines necessary for providing emergency medical care.

Premedication with antihistamine and glucocorticoid drugs is used to prevent the side effects of RCS on the eve of the X-ray contrast study, and one of the tests is also carried out to predict the patient's hypersensitivity to RCS. The most optimal tests are: determination of histamine release from peripheral blood basophils when mixed with RCS; the content of total complement in the blood serum of patients assigned for X-ray contrast examination; selection of patients for premedication by determining the levels of serum immunoglobulins.

Among the rarer complications, there may be "water" poisoning during barium enema in children with megacolon and gas (or fat) vascular embolism.

A sign of "water" poisoning, when a large amount of water is quickly absorbed through the walls of the intestine into the bloodstream and an imbalance of electrolytes and plasma proteins occurs, there may be tachycardia, cyanosis, vomiting, respiratory failure with cardiac arrest; death may occur. First aid in this case is intravenous administration of whole blood or plasma. Prevention of complications is to carry out irrigoscopy in children with a suspension of barium in an isotonic saline solution, instead of an aqueous suspension.

Signs of vascular embolism are as follows: the appearance of a feeling of tightness in the chest, shortness of breath, cyanosis, slowing of the pulse and a drop in blood pressure, convulsions, cessation of breathing. In this case, the introduction of the RCS should be immediately stopped, the patient should be placed in the Trendelenburg position, artificial respiration and chest compressions should be started, 0.1% - 0.5 ml of adrenaline solution should be injected intravenously and the resuscitation team should be called for possible tracheal intubation, artificial respiration and artificial respiration. carrying out further therapeutic measures.

Private X-ray methods.Fluorography- a method of mass in-line X-ray examination, which consists in photographing an X-ray image from a translucent screen onto a fluorographic film with a camera. Film size 110×110 mm, 100×100 mm, rarely 70×70 mm. The study is performed on a special x-ray machine - a fluorograph. It has a fluorescent screen and an automatic roll film transfer mechanism. The image is photographed using a camera on a roll film (Fig. 1.8). The method is used in a mass examination for the recognition of pulmonary tuberculosis. Along the way, other diseases can be detected. Fluorography is more economical and productive than radiography, but is significantly inferior to it in terms of information content. The dose of radiation in fluorography is greater than in radiography.

Rice. 1.8. Fluoroscopy scheme. 1 − x-ray tube; 2 - object; 3 - luminescent screen; 4 − lens optics; 5 - camera.

Linear tomography designed to eliminate the summation nature of the X-ray image. In tomographs for linear tomography, an x-ray tube and a film cassette are set in motion in opposite directions (Fig. 1.9).

During the movement of the tube and the cassette in opposite directions, an axis of movement of the tube is formed - a layer that remains, as it were, fixed, and on the tomographic image, the details of this layer are displayed as a shadow with rather sharp outlines, and the tissues above and below the layer of the axis of movement are smeared and not are revealed on the image of the specified layer (Fig. 1.10).

Linear tomograms can be performed in the sagittal, frontal and intermediate planes, which is unattainable with step CT.

X-ray diagnostics- medical and diagnostic procedures. This refers to combined X-ray endoscopic procedures with medical intervention (interventional radiology).

Interventional radiological interventions currently include: a) transcatheter interventions on the heart, aorta, arteries and veins: vascular recanalization, dissociation of congenital and acquired arteriovenous fistulas, thrombectomy, endoprosthesis replacement, installation of stents and filters, vascular embolization, closure of atrial and ventricular septal defects , selective administration of drugs to different departments vascular system; b) percutaneous drainage, filling and sclerosis of cavities of various localization and origin, as well as drainage, dilatation, stenting and endoprosthesis replacement of ducts of various organs (liver, pancreas, salivary gland, lacrimal canal, etc.); c) dilatation, endoprosthetics, stenting of the trachea, bronchi, esophagus, intestines, dilatation of intestinal strictures; d) prenatal invasive procedures, radiation interventions on the fetus under ultrasound control, recanalization and stenting fallopian tubes; e) removal of foreign bodies and stones of various nature and different localization. As a navigational (guiding) study, in addition to X-ray, an ultrasonic method is used, and ultrasonic devices are equipped with special puncture sensors. The types of interventions are constantly expanding.

Ultimately, the subject of study in radiology is the shadow image. The features of the shadow x-ray image are:

An image consisting of many dark and light areas - corresponding to areas of unequal attenuation of X-rays in different parts of the object.

The dimensions of the X-ray image are always increased (except for CT) compared to the object under study, and the larger the further the object is from the film, and the smaller the focal length (distance of the film from the focus of the X-ray tube) (Fig. 1.11).

When the object and film are not in parallel planes, the image is distorted (Figure 1.12).

Summation image (except tomography) (Fig. 1.13). Therefore, x-rays must be made in at least two mutually perpendicular projections.

Negative image on X-ray and CT.

Each tissue and pathological formations detected during radiation

Rice. 1.13. The summation nature of the x-ray image in radiography and fluoroscopy. Subtraction (a) and superposition (b) of X-ray image shadows.

research, are characterized by strictly defined features, namely: the number, position, shape, size, intensity, structure, nature of the contours, the presence or absence of mobility, dynamics over time.

Basic properties of X-rays:

1. X-rays, based on the focus of the x-ray tube, propagate in a straight line.

2. They do not deviate in an electromagnetic field.

3. The speed of their propagation is equal to the speed of light.

4. X-rays are invisible, but when absorbed by certain substances, they make them glow. This glow is called fluorescence and is the basis of fluoroscopy.

5. X-rays have a photochemical effect. This property of X-rays is the basis of radiography (the currently generally accepted method for producing X-ray images).

6. X-ray radiation has an ionizing effect and gives the air the ability to conduct electricity. Neither visible, nor thermal, nor radio waves can cause this phenomenon. Based on this property, X-rays, like the radiation of radioactive substances, are called ionizing radiation.

7. An important property of X-rays is their penetrating power, i.e. the ability to pass through the body and objects. The penetrating power of X-rays depends on:

7.1. From the quality of the rays. The shorter the length of the X-rays (i.e., the harder the X-rays), the deeper these rays penetrate and, conversely, the longer the wavelength of the rays (the softer the radiation), the shallower they penetrate.

7.2. From the volume of the body under study: the thicker the object, the more difficult it is for X-rays to “penetrate” it. The penetrating power of X-rays depends on the chemical composition and structure of the body under study. The more atoms of elements with high atomic weight and serial number (according to the periodic table) in a substance exposed to X-rays, the stronger it absorbs X-rays and, conversely, the lower the atomic weight, the more transparent the substance for these rays. The explanation for this phenomenon is that in electromagnetic radiation with a very short wavelength, which are X-rays, a lot of energy is concentrated.

8. X-rays have an active biological effect. In this case, DNA and cell membranes are critical structures.

One more circumstance must be taken into account. X-rays obey the inverse square law, i.e. The intensity of X-rays is inversely proportional to the square of the distance.

Methods of X-ray examination are divided into basic and special, private.

Basic X-ray methods. The main methods of x-ray examination include: radiography, fluoroscopy, electroroentgenography, computed x-ray tomography.

X-ray - transillumination of organs and systems using x-rays. Fluoroscopy is an anatomical and functional method that provides an opportunity to study the normal and pathological processes of organs and systems, as well as tissues by the shadow pattern of a fluorescent screen.

Advantages:

1. Allows you to examine patients in various projections and positions, due to which you can choose a position in which pathological shadow formation is better detected.

2. The possibility of studying the functional state of a number of internal organs: lungs, at various phases of respiration; pulsation of the heart with large vessels, motor function of the alimentary canal.

3. Close contact between the radiologist and the patient, which makes it possible to supplement the X-ray examination with the clinical one (palpation under visual control, targeted history), etc.

Disadvantages: relatively large radiation exposure to the patient and attendants; low throughput during the doctor's working hours; limited capabilities of the researcher's eye in detecting small shadow formations and fine tissue structures, etc. Indications for fluoroscopy are limited.

Electron-optical amplification (EOA). The operation of an electron-optical converter (IOC) is based on the principle of converting an X-ray image into an electronic image with its subsequent transformation into an amplified light image. The brightness of the screen glow is enhanced up to 7 thousand times. The use of an EOS makes it possible to distinguish details with a size of 0.5 mm, i.e. 5 times smaller than with conventional fluoroscopic examination. When using this method, X-ray cinematography can be used, i.e. recording an image on film or videotape.

Radiography is photography using x-rays. When taking X-rays, the object to be photographed must be in close contact with the cassette loaded with film. X-ray radiation coming out of the tube is directed perpendicularly to the center of the film through the middle of the object (the distance between the focus and the patient's skin under normal operating conditions is 60-100 cm). Indispensable equipment for radiography are cassettes with intensifying screens, screening grids and a special x-ray film. The cassettes are made of opaque material and correspond in size to the standard sizes of produced X-ray film (13 × 18 cm, 18 × 24 cm, 24 × 30 cm, 30 × 40 cm, etc.).

Intensifying screens are designed to increase the light effect of x-rays on photographic film. They represent cardboard, which is impregnated with a special phosphor (calcium tungsten acid), which has a fluorescent property under the influence of X-rays. Currently, screens with phosphors activated by rare earth elements are widely used: lanthanum oxide bromide and gadolinium oxide sulfite. The very good efficiency of the rare earth phosphor contributes to the high light sensitivity of the screens and ensures high image quality. There are also special screens - Gradual, which can even out the existing differences in the thickness and (or) density of the subject. The use of intensifying screens significantly reduces the exposure time for radiography.

Special movable gratings are used to filter out the soft rays of the primary flux that can reach the film, as well as the secondary radiation. Processing of the filmed films is carried out in a photo laboratory. The processing process is reduced to development, rinsing in water, fixing and thorough washing of the film in flowing water, followed by drying. Drying of films is carried out in drying cabinets, which takes at least 15 minutes. or occurs naturally, with the picture being ready the next day. When using processing machines, images are obtained immediately after the study. Advantage of radiography: eliminates the disadvantages of fluoroscopy. Disadvantage: the study is static, there is no possibility of assessing the movement of objects during the study.

Electroroentgenography. Method for obtaining x-ray images on semiconductor wafers. The principle of the method: when rays hit a highly sensitive selenium plate, the electric potential changes in it. The selenium plate is sprinkled with graphite powder. Negatively charged powder particles are attracted to those areas of the selenium layer in which positive charges have been preserved, and are not retained in those areas that have lost their charge under the action of X-rays. Electroradiography allows you to transfer the image from the plate to paper in 2-3 minutes. More than 1000 shots can be taken on one plate. The advantage of electroradiography:

1. Speed.

2. Profitability.

Disadvantage: insufficiently high resolution in the study of internal organs, a higher dose of radiation than with radiography. The method is used mainly in the study of bones and joints in trauma centers. Recently, the use of this method has been increasingly limited.

Computed X-ray tomography (CT). The creation of X-ray computed tomography was the most important event in radiation diagnostics. This is evidenced by the award Nobel Prize in 1979 to renowned scientists Cormac (USA) and Hounsfield (England) for the development and clinical testing of CT.

CT is based on the registration of X-ray radiation with sensitive dosimetric detectors and the creation of an X-ray image of organs and tissues using a computer. The principle of the method is that after the rays pass through the patient's body, they do not fall on the screen, but on the detectors, in which electrical impulses arise, which are transmitted after amplification to the computer, where they are reconstructed according to a special algorithm and create an image of the object studied on the monitor. The image of organs and tissues on CT, unlike traditional x-rays, is obtained in the form of transverse sections (axial scans). On the basis of axial scans, an image reconstruction is obtained in other planes.

In the practice of radiology, three types of computed tomographs are currently used: conventional step, spiral or screw, multislice.

In conventional stepping CT scanners, high voltage to x-ray tube supplied by high voltage cables. Because of this, the tube cannot rotate continuously, but must perform a rocking motion: one turn clockwise, stop, one turn counterclockwise, stop and back. As a result of each rotation, one image with a thickness of 1 - 10 mm is obtained in 1 - 5 seconds. In the interval between slices, the tomograph table with the patient moves to a set distance of 2–10 mm, and the measurements are repeated. With a slice thickness of 1 - 2 mm, stepping devices allow you to perform research in the "high resolution" mode. But these devices have a number of disadvantages. Scan times are relatively long and motion and breath artifacts may appear on images. Image reconstruction in projections other than axial ones is difficult or simply impossible. There are serious limitations when performing dynamic scanning and studies with contrast enhancement. In addition, small formations between sections may not be detected if the patient's breathing is uneven.

Multislice (multi-detector) CT scanners are equipped with 4, 8, 16, 32 and even 128 rows of detectors. In multislice devices, the scan time is significantly reduced and the spatial resolution in the axial direction is improved. They can obtain information using a high-resolution technique. The quality of multiplanar and volumetric reconstructions is significantly improved.

CT has a number of advantages over conventional X-ray examination:

1. First of all, high sensitivity, which makes it possible to differentiate individual organs and tissues from each other in terms of density up to 0.5%; on conventional radiographs, this figure is 10-20%.

2. CT allows you to get an image of organs and pathological foci only in the plane of the examined section, which gives a clear image without layering the formations lying above and below.

3. CT makes it possible to obtain accurate quantitative information about the size and density of individual organs, tissues and pathological formations.

4. CT makes it possible to judge not only the state of the organ under study, but also the relationship of the pathological process with surrounding organs and tissues, for example, tumor invasion into neighboring organs, the presence of other pathological changes.

5. CT allows you to get topograms, i.e. a longitudinal image of the area under study, like an x-ray, by moving the patient along a fixed tube. Topograms are used to establish the extent of the pathological focus and determine the number of sections.

6. CT is indispensable for radiotherapy planning (radiation mapping and dose calculation).

Diagnosis by CT is based on direct radiographic features, i.e. determining the exact localization, shape, size of individual organs and the pathological focus and, most importantly, on indicators of density or absorption. The absorbance index is based on the degree to which an X-ray beam is absorbed or attenuated as it passes through the human body. Each tissue, depending on the density of the atomic mass, absorbs radiation differently, therefore, at present, the absorption coefficient (HU) on the Hounsfield scale has been developed for each tissue and organ. According to this scale, HU of water is taken as 0; bones with the highest density - for +1000, air, which has lowest density, – for -1000.

The minimum size of a tumor or other pathological focus, determined by CT, ranges from 0.5 to 1 cm, provided that the HU of the affected tissue differs from that of healthy tissue by 10–15 units.

The disadvantage of CT is the increased radiation exposure to patients. Currently, CT accounts for 40% of the total radiation dose received by patients during X-ray diagnostic procedures, while the CT examination itself accounts for only 4% of all X-ray examinations.

In both CT and X-ray examinations, it becomes necessary to use the “image enhancement” technique to increase the resolution. Contrast in CT is performed with water-soluble radiopaque agents.

The “enhancement” technique is carried out by perfusion or infusion administration of a contrast agent.

Such methods of X-ray examination are called special. The organs and tissues of the human body become visible if they absorb x-rays to varying degrees. Under physiological conditions, such differentiation is possible only in the presence of natural contrast, which is determined by the difference in density (the chemical composition of these organs), size, and position. The bone structure is well detected against the background of soft tissues, the heart and large vessels against the background of airy lung tissue, however, the chambers of the heart under conditions of natural contrast cannot be distinguished separately, as well as the organs of the abdominal cavity, for example. The need to study organs and systems with the same density by X-rays led to the creation of a technique for artificial contrasting. The essence of this technique is the introduction of artificial contrast agents into the organ under study, i.e. substances having a density different from the density of the organ and its environment.

Radiocontrast agents (RCS) are usually divided into substances with high atomic weight (X-ray positive contrast agents) and low (X-ray negative contrast agents). The contrast agents must be harmless.

Contrast agents that absorb intensely x-rays (positive radiopaque agents) are:

1. Suspensions of salts of heavy metals - barium sulfate, used to study the gastrointestinal tract (it is not absorbed and excreted through natural routes).

2. Aqueous solutions of organic iodine compounds - urographin, verografin, bilignost, angiographin, etc., which are introduced into the vascular bed, enter all organs with the blood flow and give, in addition to contrasting the vascular bed, contrasting other systems - urinary, gallbladder, etc. .d.

3. Oily solutions of organic compounds of iodine - iodolipol, etc., which are injected into fistulas and lymphatic vessels.

X-ray negative or negative contrast agents - air, gases "do not absorb" x-rays and therefore shade well the organs and tissues under study, which have a high density.

Artificial contrasting according to the method of administration of contrast agents is divided into:

1. The introduction of contrast agents into the cavity of the organs under study (the largest group). This includes studies of the gastrointestinal tract, bronchography, fistula studies, all types of angiography.

2. The introduction of contrast agents around the organs under study - retropneumoperitoneum, pneumothorax, pneumomediastinography.

3. The introduction of contrast agents into the cavity and around the organs under study. This includes parietography. Parietography in diseases of the gastrointestinal tract consists in obtaining images of the wall of the investigated hollow organ after the introduction of gas, first around the organ, and then into the cavity of this organ.

4. A method based on the specific ability of some organs to concentrate individual contrast agents and at the same time shade it against the background of surrounding tissues. These include excretory urography, cholecystography.

Side effects of RCS. Body reactions to the introduction of RCS are observed in approximately 10% of cases. By nature and severity, they are divided into 3 groups:

1. Complications associated with the manifestation of a toxic effect on various organs with functional and morphological lesions of them.

2. The neurovascular reaction is accompanied by subjective sensations (nausea, sensation of heat, general weakness). Objective symptoms in this case are vomiting, lowering blood pressure.

3. Individual intolerance to RCS with characteristic symptoms:

3.1. From the side of the central nervous system - headaches, dizziness, agitation, anxiety, fear, the occurrence of convulsive seizures, cerebral edema.

3.2. Skin reactions - hives, eczema, itching, etc.

3.3. Symptoms related to dysfunction of cardio-vascular system- pallor of the skin, discomfort in the region of the heart, drop in blood pressure, paroxysmal tachycardia or bradycardia, collapse.

3.4. Symptoms associated with respiratory failure - tachypnea, dyspnea, asthma attack, laryngeal edema, pulmonary edema.

RCS intolerance reactions are sometimes irreversible and fatal.

In mild cases of adverse reactions, it is enough to stop the injection of RCS and all phenomena, as a rule, disappear without therapy.

In case of severe complications, it is necessary to immediately call the resuscitation team, and before it arrives, inject 0.5 ml of adrenaline, intravenously 30-60 mg of prednisolone or hydrocortisone, 1-2 ml of an antihistamine solution (diphenhydramine, suprastin, pipolfen, claritin, hismanal), intravenously 10 % calcium chloride. In case of laryngeal edema, tracheal intubation should be performed, and if it is impossible, tracheostomy should be performed. In case of cardiac arrest, immediately begin artificial respiration and chest compressions without waiting for the arrival of the resuscitation team.

Among the rarer complications, there may be "water" poisoning during barium enema in children with megacolon and gas (or fat) vascular embolism.

Signs of vascular embolism are: the appearance of a feeling of tightness in the chest, shortness of breath, cyanosis, slowing of the pulse and a drop in blood pressure, convulsions, cessation of breathing. In this case, the introduction of the RCS should be immediately stopped, the patient should be placed in the Trendelenburg position, artificial respiration and chest compressions should be started, 0.1% - 0.5 ml of adrenaline solution should be injected intravenously and the resuscitation team should be called for possible tracheal intubation, artificial respiration and artificial respiration. carrying out further therapeutic measures.

Private X-ray methods. Fluorography is a method of mass flow x-ray examination, which consists in photographing an x-ray image from a translucent screen onto film with a camera.

Tomography (conventional) is designed to eliminate the summation nature of the x-ray image. Principle: during the shooting process, the X-ray tube and film cassette move synchronously relative to the patient. As a result, a clearer image of only those details that lie in the object at a given depth is obtained on the film, while the image of the details located above or below becomes blurred, “smeared”.

Polygraphy is the obtaining of several images of the organ under study and its part on one radiograph. Several shots are taken (mostly 3) on one film after a certain time.

X-ray kymography is a method of objective registration of the contractility of the muscle tissue of functioning organs by changing the contour of the image. The picture is taken through a moving slit-like lead grating. In this case, the oscillatory movements of the organ are recorded on the film in the form of teeth that have a characteristic shape for each organ.

Digital radiography - includes the detection of a ray pattern, image processing and recording, image presentation and viewing, information storage.

Currently, four digital radiography systems have been technically implemented and have already received clinical use:

1. digital radiography from the image intensifier screen;

2. digital fluorescent radiography;

3. scanning digital radiography;

4. digital selenium radiography.

The system of digital radiography from the image intensifier tube consists of an image intensifier tube, a television path and an analog-to-digital converter. The image intensifier tube is used as an image detector. The television camera converts the optical image on the image intensifier tube into an analog video signal, which is then formed into a digital data set using an analog-to-digital converter and transferred to a storage device. The computer then converts this data into visible image on the monitor screen. The image is studied on the monitor and can be printed on film.

In digital fluorescent radiography, after exposure to X-rays, luminescent memory plates are scanned by a special laser device, and the light beam that occurs during laser scanning is transformed into a digital signal that reproduces an image on a monitor screen or is printed. Luminescent plates are built into conventional sized cassettes, which can be used multiple times (from 10,000 to 35,000 times) with any X-ray machine.

Benefits of digital radiography:

1. Improving image quality and expanding diagnostic capabilities.

2. Increasing the efficiency of equipment use.

3. Reduction of dose loads on patients and medical personnel.

4. The possibility of combining various equipment of the radiology department into a single network.

5. Possibility of integration into the general local network of the institution (“electronic medical history”).

6. Possibility of organizing remote consultations (“telemedicine”).

X-ray diagnostics - medical and diagnostic procedures. This refers to combined X-ray endoscopic procedures with medical intervention (interventional radiology).

Interventional radiological interventions currently include: a) transcatheter interventions on the heart, aorta, arteries and veins: vascular recanalization, dissociation of congenital and acquired arteriovenous fistulas, thrombectomy, endoprosthesis replacement, installation of stents and filters, vascular embolization, closure of atrial and ventricular septal defects , selective administration of drugs into various parts of the vascular system; b) percutaneous drainage, filling and sclerosis of cavities of various localization and origin, as well as drainage, dilatation, stenting and endoprosthesis replacement of ducts of various organs (liver, pancreas, salivary gland, lacrimal canal, etc.); c) dilatation, endoprosthetics, stenting of the trachea, bronchi, esophagus, intestines, dilatation of intestinal strictures; d) prenatal invasive procedures, radiation interventions on the fetus under ultrasound control, recanalization and stenting of the fallopian tubes; e) removal of foreign bodies and stones of various nature and different localization. As a navigational (guiding) study, in addition to X-ray, an ultrasonic method is used, and ultrasonic devices are equipped with special puncture sensors. The types of interventions are constantly expanding.

Ultimately, the subject of study in radiology is the shadow image. The features of the shadow x-ray image are:

1. An image consisting of many dark and light areas - corresponding to areas of unequal attenuation of X-rays in different parts of the object.

2. The dimensions of the x-ray image are always enlarged (except for CT) compared to the object under study, and the larger the farther the object is from the film, and the smaller the focal length (distance of the film from the focus of the x-ray tube).

3. When the object and film are not in parallel planes, the image is distorted.

4. Summation image (except tomography). Therefore, x-rays must be made in at least two mutually perpendicular projections.

5. Negative image on X-ray and CT.

Each tissue and pathological formations detected during X-ray examination are characterized by strictly defined features, namely: number, position, shape, size, intensity, structure, nature of the contours, the presence or absence of mobility, dynamics over time.

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