Advantages of radioisotope testing of the kidneys. Radioisotope research methods: diagnostics and scanning

Radioisotope diagnostics is one of the most informative research methods. With its help they carry out full diagnostics functioning systems internal organs, all possible violations and deviations from the norms are noted.

Radio isotope renography kidney is the most popular and frequently produced radioisotope research method throughout the world.

The essence of diagnosis, goals and advantages

The kidneys act as the main cleansing system of the body. With their help, blood is filtered, which is cleansed of various toxins and other harmful substances. Conventional testing, such as blood and urine tests, can reveal various disorders in the work of the body, to establish the cause of these violations.

Well, radioisotope renography makes it possible to see exactly how the filtration process occurs, to display the work of glomeruli in currently time, and also monitor the work of organs separately.

The main purpose of renography is precisely to display the work of internal organs, analyze and monitor their condition. Based on the data from this study, accurate diagnosis it is impossible to diagnose, but you can clearly see various disturbances in the functioning of internal organs, as well as monitor the effectiveness of therapy.

The main advantage of kidney renography is the simplicity of the procedure, which requires virtually no additional preparation and the absence of high doses of radiation. Renography is prescribed to all patients who have obvious kidney problems.

Radioisotope research methods

Based on the research results that need to be obtained for an informative picture, there are several methods for conducting radioisotope diagnostics. Each of these methods is special in its own way, and the totality of research results reflects a complete picture of kidney function:

1. Renography. This technique is not based on visualization of images of the kidneys, but on quantitative indicators of blood filtration, the rate of formation and outflow of urine. This is the main research method urinary system, with which you can assess the severity of violations, minor deviations from the norm, and track the dynamics of all functional indicators.
2. Scanning. Static renography, or scanning, is a test that produces schematic illustration the organ being studied. This helps determine the shape, size, internal position, and placement in proportion to other organs. Diagnosis is carried out with a special scanner that detects radiation from a contrast agent previously introduced into the body. The entire procedure will take about one to two hours, since studies can be carried out only 40 minutes after the contrast is administered.
3. . This method is also based on obtaining high-quality images of internal organs. A special gamma tomograph records radiation, on the basis of which an image is formed. After collecting all the radiation, the device analyzes all the data and after some time creates an image. The images obtained in this study are clearer and you can see the smallest changes. That is why, with the help of scintigraphy, it is possible to study in detail the functioning of the entire urinary system, examining not only the kidneys, but also all the urinary canals.

Indications for examination

Any nephrological pathologies of paired organs, the slightest deviations from the norm in basic blood and urine tests, previously serious illnesses, chronic diseases kidneys, etc., are indisputable indications for renographic examination. Most often, the procedure is prescribed if there is mechanical damage kidneys (deformation, inflammation, rupture). Radioisotope renography is also performed for any diseases of the urinary system:

Diagnosis is also carried out for secondary diseases that have led to disturbances in the functioning of organs:

• arterial hypertension;
• autoimmune diseases, causing lesions connective tissues;

It is worth considering that the doctor may prescribe this study for other diseases that can cause complications in the functioning of the kidneys and adrenal glands. Renography is also used as observation after surgical manipulation of internal organs, during donation (transplantation).

Preparation for the procedure

All the beauty this method examination is that it does not require any special preliminary preparation. But there are still certain requirements that should be adhered to when carrying out this procedure, namely:

During the examination, there should not be any metal objects (jewelry, piercings) on the patient’s body.

How is the examination done?

Before the examination, it is necessary to administer a contrast agent – ​​hippuran. If you are allergic to contrast, it is replaced with an analogue. The patient should take a sitting position. Next, special detectors are attached to the body, which are placed at the level of the kidneys, heart and above the largest blood vessels. The device draws curved lines that characterize the purification of the blood in the kidneys from the contrast agent. After this, all the drawn curves are studied in detail, taking into account the segments.

The secret segment shows the accumulation of contrast in the vessels of the kidneys, that is, it draws vascular lines. The excretory segment shows the release of contrast along with urine. These two curves are the main indicator of the state of absorption and excretion. The time it takes the device to draw these curves is also taken into account.

The longer the examination takes, the longer the blood is filtered, which indicates the presence of diseases. If the device cannot complete the curve within 40 minutes, you can safely declare the presence renal failure. In addition, this examination method can reveal not only an obvious problem of excretory function, but also latent renal failure, which cannot be diagnosed using conventional blood, urine or x-ray tests.

This study is considered the most informative in its field, as well as accessible. With its help, you can assess the condition of the kidneys, the quality of their work, and also examine the superficial urinary tract.

Important! If the patient has thrombosis or occlusion of the arteries, afunctional blood occurs, which sharply reduces the vascular segment, which significantly affects the drawing of curves during the examination.

Features of the study in children

Development kidney diseases, insufficiency, weak activity of the adrenal glands, low threshold filtration and many other pathologies, in 80% of cases they are diagnosed in children. Everything is connected with the development of this organ. The fact is that the kidneys do not grow proportionally. In children under 12 years of age, they are almost half as much as necessary, in relation to the entire body.

Therefore, the kidneys experience enormous stress and often fail. For examination child's body In almost all cases, radioisotope renography is prescribed, where the amount of harmful radiation exposure is 80-100 times lower than with conventional x-rays.

The only limitation for this type of research is the age of up to 1 year. But if absolutely necessary, this study can be applied in such early age. In all other cases, children are given potassium iodide before the procedure, which reduces the effects of radiation, and a mesh is drawn on the body (in the area where the device is connected) with iodine. For neurological disorders, children are given a mild sedative.

Analysis of results

The curve displayed on paper is divided into three parts:

1. Vascular curve, which shows the period of time during which hippuron appears in the vessels.
2. Kanaltsevaya– epithelial secretion of tubular substances.
3. Curve showing the yield of spent isotope from the kidneys.

The curve is plotted on two axes, the first value of which is the time range, and the second, the percentage of contrast agent concentration. According to international standards, the following indicators are considered the norm:

1. The maximum concentration of the substance can appear in 3 – 4 minutes.
2. The half-life (double the curve) is 10 to 12 minutes.
3. The difference in these indicators between each of their kidneys is no more than 20%. Since one kidney is smaller than the other, a slight deviation is acceptable.

According to this graph, you can determine the time when a deviation occurs in the functioning of organs and to what extent this happens. With help this study it is possible to assess the quality of excretory and secretory functions kidneys, degree of filtration, obtain clear information about the size and shape of the organs being studied, study the work of superficial urinary tract, as well as identify renal failure before it occurs clinical manifestations. This will significantly facilitate treatment and reduce the risk by half.

Pathological types of curves

The results of renographic studies are very specific, they are divided into types:

1. Afunctional– smooth decrease in the curve in the vascular segment.
2. Isusthenuric– an increase in the curve to a certain level, which indicates the presence of chronic renal failure.
3. Obstructive– a gradual elevation of the curve in the absence of a complete outflow of urine. Most often, the cause lies in stones or inflammation blocking the urinary tract.
4. Parenchymatous– a significant slowdown in all indicators, the line remains virtually unchanged. The main problem is.

Remember! According to the results of this study, it is impossible to make an accurate diagnosis. Renography only evaluates the condition of the organs!

Precautions and contraindications

Diagnostics of the kidneys by radiation does not have any contraindications, but there are still some precautions for its implementation. These include:

• age of children under 1 year;
• the presence of thrombosis and other cardiovascular diseases;
• overweight;
• taking psychotropic and sedative drugs.

It is worth remembering that these factors are not a list of contraindications; they only affect the reliability and accuracy of the results of the examination. The only contraindication is if the patient is allergic to the contrast agent or iodine. But even this will not be a problem, since hippuran can be easily replaced with a similar contrast.

Radioisotope studies of the kidneys are often used to diagnose nephrological pathologies. The procedure has become widespread due to its accessibility and information content - it costs much less than magnetic resonance imaging, but is just as effective. In addition, this type of research is relatively safe and has few contraindications.

Radioisotope research is a popular procedure for its accessibility and information content, which allows you to see some kidney pathologies.

What is this procedure?

Isotope renography is X-ray examination nephrological system using a radioactive pharmaceutical injected into the patient’s plasma.

A specific reagent is injected into the patient’s vein, after which it spreads evenly throughout the body. Iodine isotopes are often used. Using a special device, the doctor observes the rate at which the radioisotope moves through the body and identifies places where it accumulates excessively. The result obtained can be in the form of a graph or a full-fledged image, depending on the type of procedure chosen. The analysis option is determined according to the information needed for the diagnosis.

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Types of research

Radioisotope research has variations:

• radiometry;
• radiography;
• scintigraphy;
• scanning.

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Why is it necessary?

Radioisotope diagnostics pursues the following goals:

• assessment of the condition of the nephrological system after injury;
• identification of chronic diseases such as glomerulonephritis, pyelonephritis;
• diagnosis of the consequences of prolonged urinary retention;
• monitoring the transplanted kidney;
• identification of anatomical disorders acquired as a result of various systemic diseases.

The examination is considered one of the most informative diagnostic methods. Unlike ultrasound, RXR allows you to evaluate not only anatomical features and pathology, but also to empirically examine the functional abilities of the kidneys. Thanks to the graphs obtained during the analysis, the doctor assesses the patency vascular system and the rate of removal of contrast from the kidneys.

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What preparation?

Isotope renography of the kidneys, like any medical analysis, requires minimal preparation from the patient. Taking drugs is completely prohibited alcoholic drinks and psychotropic substances. The last meal takes place 4-6 hours before the test; sometimes the patient is advised to drink a glass of non-carbonated water immediately before the test. If for health reasons the patient is forced to take medications, it is necessary to discuss this with the doctor, since there are contraindications to the use of medications before radioisotope analysis. During the examination, it is necessary to remove all metal devices and jewelry. Failure to comply with these rules leads to false results.

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Radioisotope testing is an absolutely painless procedure that does not require hospitalization before or hospital observation after.

The isotope that is injected into the vein before the test is the only unpleasant part of the analysis. The patient sits down, special suction cups - sensors - are attached to his back, at the level of the heart muscle, kidneys and Bladder. Lying position, used only in special cases severe cases and in the study of children. Sensors attached to the body record information and display it graphically in the form of two curves. Analysis of the organs of people who are obese or have anatomical abnormalities requires preliminary x-rays. If the study involves scanning, the special apparatus, which, reacting to waves of a radioactive drug, forms a visual projection of the kidneys. The duration of the procedure does not exceed half an hour. After the study, the radioisotope leaves urinary system naturally. To speed up withdrawal, the patient is prescribed to drink a lot of water.

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How is it done for a child?

Radionuclide renography is not used for diagnosing children under one year of age; according to other sources, the limitation applies to the first three years of life. In the early childhood, used for kidney research screening ultrasound. If a radioisotope analysis is nevertheless prescribed, before the procedure little patient give potassium iodide, which reduces negative impact radiation to the thyroid gland. Since the examination requires long-term adherence to a certain body position, the youngest patients are given a mild sedative.

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Safety

Many patients are concerned about the consequences of introducing a radioactive drug into the blood. However, the radiation dose received during the procedure is significantly lower than with x-rays. An important aspect is that RRG can be carried out several times a year, while X-ray analysis can be done only once. The drug used for analysis is stored in a special laboratory; expiration dates and medication records are strictly monitored. The dose is calculated individually for each patient, based on information about his age, weight and health status. The kidney examination is carried out in a special room lined with protective panels that prevent radiation from escaping. After the working day, personnel working in the radiology department are monitored using a dosimeter. This minimizes the risk of radioactive particles reaching patients.

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The essence of the technique

The radioisotope research method is carried out by introducing a special contrast agent into the patient’s body, which is then excreted along with the urine. As this drug passes through the desired organ, contrast images are taken. Any contrast agent used contains iodine; it can be absorbed by organ tissues, illuminating them.

On normal x-ray It is quite difficult for doctors to distinguish the structure of organs, as well as to determine the presence of changes that have arisen as a result of the course of diseases. After the administration of a contrast agent, the structure of the organs becomes clearly visible both on a conventional x-ray and during computed tomography.

The contrast agent is injected intravenously, and sensors are attached to the patient’s body to detect radiation in the organs and blood.

Indications for the study

Radioisotope diagnostics is used for the following purposes:

• identification of acute and chronic diseases;
• assessment of the condition of organs in case of injury;
• diagnosis of structural disorders of organs as a result of diseases;
• assessing the condition of the organ after transplantation.

In addition, this technique helps to determine existing disturbances in the outflow of urine and blood circulation.

In what areas of medicine is it used?

The radioisotope research method is based on the participation of radionuclides in physiological processes body. Circulating along with lymph and blood, the injected contrast agent is retained in certain organs, and their speed and direction are also recorded, resulting in a diagnosis.

The radioisotope research method is used in gastroenterology and allows you to determine the position, functioning and size of salivary glands, spleen, and gastrointestinal tract. In addition, you can examine the liver, evaluate its work, the peculiarities of its blood circulation, which is especially important:

• with chronic hepatitis;
• cirrhosis;
• malignant neoplasms.

Using a contrast agent, you can analyze the condition of the pancreas and stomach during peptic ulcer and chronic gastroenteritis.

In hematology, this research method helps to determine the presence of anemia. In cardiology, the movement of blood through the vessels and cavities of the heart muscle is observed. Based on the nature of the distribution of the contrast agent in healthy and affected areas, a conclusion is made regarding the course of the disease.

The radioisotope method of studying the kidneys allows us to determine the peculiarities of the functioning of this organ, the presence of various diseases, as well as the degree of damage. In neurology, this method is used to identify brain tumors, their nature, prevalence and location.

With the advent of the radioisotope research method, completely new opportunities for oncology appeared. By using this diagnostic, it is possible to identify malignant neoplasms in the initial stages:

• intestines;
• lungs;
• nervous system;
• pancreas.

This makes it possible to evaluate the effectiveness of treatment and determine relapses. Moreover, you can see signs of bone metastases, which are detected several months earlier than x-rays.

Preparing for diagnosis

The Center for Modern Medicine conducts radioisotope research at the very high level using modern tools and drugs. You need to visit the doctor in advance and discuss with him all the available nuances and features of this procedure. Certain preparation of the patient for radioisotope research methods is required. Renography requires the patient to give up alcoholic beverages, and it is also necessary to adjust the intake of medications.

During the procedure, there should be absolutely no metal objects on the patient’s body. The administration of a contrast agent should be carried out strictly on an empty stomach, since after the drug enters the body, nausea, fever, and sweating may occur. Normally, contrast removal occurs within 24 hours.

If there is a need for radioisotope testing during pregnancy and children, then a few hours before the procedure they should take potassium iodide to reduce exposure dangerous drugs on the thyroid gland.

Features of the event

When performing a procedure at the Center for Modern Medicine, for example, a contrast agent is initially injected into the patient’s body. Then it is laid out so that it can be obtained high quality pictures. Usually, the posterior surface of the organ is initially examined, and then the anterior one.

From the very beginning, pictures are taken at a speed of 1 frame per second, and this happens for 1 minute. After this, the distribution of the drug throughout the organs is assessed. To do this, sensor readings are taken at a speed of 1 frame per minute, and so on for 20 minutes. The examination continues until the contrast is excreted along with the urine. If necessary, bladder catheterization is performed.

Decoding the results

The maximum concentration of the contrast agent is observed approximately 5 minutes after its administration, and after 30 minutes its concentration decreases significantly, by about 3 times. During this time, it is possible to evaluate the functioning of the organ under study, its location and clarity internal structure. The presence of dark spots may indicate a pathological process.

When performing diagnostics, the obtained images are evaluated in combination with the data in the renogram.

Precautionary measures

Radioisotope research methods have indications and contraindications, which is why it is imperative to take this into account, as there may be serious problems with the body. This method of examination is quite unsafe. A person receives a certain dose of radiation, so it cannot be used during pregnancy or children without serious indications. In addition, its use in patients with iodine or seafood intolerance is prohibited.

Some people may distort the results obtained. medications, in particular blood pressure lowering agents, as well as psychotropic medications. You cannot conduct more than one study per day, since otherwise An excess of contrast agent in the blood can distort the results.

To ensure greater safety during diagnostic procedures the patient must be in a room covered with protective panels. The contrast agent itself must be stored in special cabinets that prevent the spread of radiation.

Conducting research in children

For children, this research technique is prescribed in the presence of renal failure, when other examination methods are uninformative or difficult to perform. With the help of such a technique it is possible to detect the most early manifestations diseases.

In children with severe kidney dysfunction, changes are immediately noticeable, and the levels of abnormality in the blood increase sharply.

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Radioisotope renography of the kidneys - what is it?

The effectiveness of the kidneys is determined by their ability to filter the blood from harmful substances and remove them from the body. Laboratory diagnostics reveals a decrease in the filtration capacity of glomeruli thanks to laboratory blood tests: if the concentration of harmful substances in the blood is higher than normal, and in the urine, accordingly, lower, it means that the kidneys are not coping well with the physiological task.

But isotope renography of the kidneys allows you to “see” the work of the glomeruli in real time. Moreover, it makes it possible to consider the functioning of the kidneys separately.

Using this study, it is impossible to make an accurate diagnosis, but it is definitely possible to identify the slightest deviations from normal indicators glomerular filtration rate. Thus, renal failure can be detected even at a latent, asymptomatic stage.

Indications

The indication for kidney renography is early diagnosis if the presence of nephrological pathologies is suspected. The most relevant procedure is for diagnosing unilateral kidney damage, but given the fact that it is difficult to identify the fact of damage to only one kidney at the initial stage without this procedure.

Radioisotope renography is performed for any pathology of the urinary system:

• pyelonephritis;
• renal failure of any origin;
• hydronephrosis1;
• urolithiasis.

Research is also being carried out on other diseases that affect the functioning of the kidneys, interfering with their efficiency.

In other words, for secondary nephrological diseases provoked by:

• arterial hypertension;
• autoimmune connective tissue lesions;
• amyloidosis.

Renography is also necessary for postoperative observation when conducting surgical methods kidney treatment or organ transplantation.

Preparation

The advantage of radioisotope renography is the fact that it does not require preparation and has no contraindications. Any person in need of diagnosis can undergo the procedure, regardless of how they feel, accompanying illnesses, age.

How do they do it?

The process of studying the effectiveness of the filtration activity of the kidneys takes about half an hour. The patient must remain seated throughout the entire procedure.

After this, the diagnostician injects a radioactive substance intravenously into the patient: sodium salt o-iodohypuric acid, called hippuran.

For the next half hour, the patient will need to sit, waiting for the moment when the radiograph recorder finishes taking and recording readings. Its main task is to record the time of appearance of hippuran in the blood and its half-life (removal of half of the administered amount from the blood).

The resulting graphs will give the nephrologist the opportunity to get an objective idea of ​​the filtration abilities of both kidneys separately.

Kidney renography results

Decoding indicators

The result of the half-hour procedure are graphs in which horizontal axis indicates time in minutes, and vertical indicates radioactivity in percent.

The kidney function graph is a curve that can be divided into three fragments:

• vascular - the graph curve goes sharply upward: this reflects the appearance of a radioactive drug in the blood;
• tubular - this fragment of the graph shows the work of the glomeruli to cleanse the blood of hippuran;
• excretory - the radioactive substance leaves the blood along with the urine, the curve graph goes down.

Indicators are considered normal when maximum estrus is reached in 3-4 minutes, and the hippuran excretion time is up to 12 minutes. A difference between the indicators of two kidneys is allowed, but it should not be more than 20%.

Evidence of impaired glomerular filtration is mainly the curvature of the second fragment of the graph. The closer this line is to the horizontal, the longer this period lasts, therefore, the rate of blood filtration is reduced and kidney function is impaired.

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The essence of diagnosis, goals and advantages

The kidneys act as the main cleansing system of the body. With their help, blood is filtered, which is cleansed of various toxins and other harmful substances. Conventional research methods, such as blood and urine tests, can reveal various disorders in the functioning of the organ and determine the cause of these disorders.

Well, radioisotope renography makes it possible to see exactly how the filtration process occurs, display the work of the glomeruli at the current moment in time, and also monitor the work of the organs individually.

The main purpose of renography is precisely to display the work of internal organs, analyze and monitor their condition. Based on the data from this study, an accurate diagnosis cannot be made, but it is definitely possible to see various disturbances in the functioning of internal organs, as well as monitor the effectiveness of therapy.

The main advantage of kidney renography is the simplicity of the procedure, which requires virtually no additional preparation and the absence of high doses of radiation. Renography is prescribed to all patients who have obvious kidney problems.

Radioisotope research methods

Based on the research results that need to be obtained for an informative picture, there are several methods for conducting radioisotope diagnostics. Each of these methods is special in its own way, and the totality of research results reflects a complete picture of kidney function:

1. Renography. This technique is not based on visualization of images of the kidneys, but on quantitative indicators of blood filtration, the rate of formation and outflow of urine. This is the main method of studying the urinary system, with which you can assess the severity of disorders, minor deviations from the norm, and track the dynamics of all functional indicators.
2. Scanning. Static renography, or scanning, is a study that produces a schematic image of the organ being examined. This helps determine the shape, size, internal position, and placement in proportion to other organs. Diagnosis is carried out with a special scanner that detects radiation from a contrast agent previously introduced into the body. The entire procedure will take about one to two hours, since studies can be carried out only 40 minutes after the contrast is administered.
3. Scintigraphy. This method is also based on obtaining high-quality images of internal organs. A special gamma tomograph records radiation, on the basis of which an image is formed. After collecting all the radiation, the device analyzes all the data and after some time creates an image. The images obtained in this study are clearer and you can see the smallest changes. That is why, with the help of scintigraphy, it is possible to study in detail the functioning of the entire urinary system, examining not only the kidneys, but also all the urinary canals.

Indications for examination

Any nephrological pathologies of paired organs, the slightest deviations from the norm in basic blood and urine tests, previous serious illnesses, chronic kidney diseases, etc., are indisputable indications for renographic examination. Most often, the procedure is prescribed in the presence of mechanical damage to the kidneys (deformation, inflammation, rupture). Radioisotope renography is also performed for any diseases of the urinary system:

Diagnosis is also carried out when secondary diseases nephrological nature, which led to disturbances in the functioning of organs:

• arterial hypertension;
• autoimmune diseases that cause connective tissue damage;
• amyloidosis.

It is worth considering that the doctor may prescribe this study for other diseases that can cause complications in the functioning of the kidneys and adrenal glands. Renography is also used as observation after surgical manipulations of internal organs, during donation (transplantation, transplantation).

Preparation for the procedure

The beauty of this examination method is that it does not require any special preliminary preparation. But there are still certain requirements that should be adhered to when carrying out this procedure, namely:

How is the examination done?

Before the examination, it is necessary to administer a contrast agent – ​​hippuran. If you are allergic to contrast, it is replaced with an analogue. The patient should take a sitting position. Next, special detectors are attached to the body, which are placed at the level of the kidneys, heart and above the largest blood vessels. The device draws curved lines that characterize the purification of the blood in the kidneys from the contrast agent. After this, all the drawn curves are studied in detail, taking into account the segments.

The secret segment shows the accumulation of contrast in the vessels of the kidneys, that is, it draws vascular lines. The excretory segment shows the release of contrast along with urine. These two curves are the main indicator of the state of the absorption and excretion function of the kidneys. The time it takes the device to draw these curves is also taken into account.

The longer the examination takes, the longer the blood is filtered, which indicates the presence of diseases. If the device cannot complete the curve within 40 minutes, you can safely declare the presence of renal failure. In addition, this examination method can reveal not only an obvious problem of excretory function, but also latent renal failure, which cannot be diagnosed using conventional blood, urine or x-ray tests.

This study is considered the most informative in its field, as well as accessible. With its help, you can assess the condition of the kidneys, the quality of their work, and also examine the superficial urinary tract.

Features of the study in children

The development of kidney diseases, failure, weak activity of the adrenal glands, low filtration threshold and many other pathologies are diagnosed in children in 80% of cases. Everything is connected with the development of this organ. The fact is that the kidneys do not grow proportionally. In children under 12 years of age, they are almost half as much as necessary, in relation to the entire body.

Therefore, the kidneys experience enormous stress and often fail. To examine a child’s body, in almost all cases radioisotope renography is prescribed, where the amount of harmful radiation exposure is 80-100 times lower than with conventional x-rays.

The only limitation for this type of research is the age of up to 1 year. But if absolutely necessary, this research can be applied at such an early age. In all other cases, children are given potassium iodide before the procedure, which reduces the effects of radiation, and a mesh is drawn on the body (in the area where the device is connected) with iodine. For neurological disorders, children are given a mild sedative.

Analysis of results

The curve displayed on paper is divided into three parts:

1. Vascular curve, which shows the period of time during which hippuron appears in the vessels.
2. Kanaltsevaya– epithelial secretion of tubular substances.
3. Curve showing the yield of spent isotope from the kidneys.

The curve is plotted on two axes, the first value of which is the time range, and the second, the percentage of contrast agent concentration. According to international standards, the following indicators are considered the norm:

1. The maximum concentration of the substance can appear in 3 – 4 minutes.
2. The half-life (double the curve) is 10 to 12 minutes.
3. The difference in these indicators between each of their kidneys is no more than 20%. Since one kidney is smaller than the other, a slight deviation is acceptable.

According to this graph, you can determine the time when a deviation occurs in the functioning of organs and to what extent this happens. Using this study, it is possible to assess the quality of excretory and secretory functions of the kidneys, the degree of filtration, obtain clear information about the size and shape of the organs being studied, study the functioning of the superficial urinary tract, and also identify renal failure before its clinical manifestations appear. This will significantly facilitate treatment and halve the risk of dialysis.

Pathological types of curves

The results of renographic studies are very specific, they are divided into types:

1. Afunctional– smooth decrease in the curve in the vascular segment.
2. Isusthenuric– an increase in the curve to a certain level, which indicates the presence of chronic renal failure.
3. Obstructive– a gradual elevation of the curve in the absence of a complete outflow of urine. Most often, the cause lies in stones or inflammation blocking the urinary tract.
4. Parenchymatous– a significant slowdown in all indicators, the line remains virtually unchanged. The main problem is glomerulonephritis.

Precautions and contraindications

Diagnostics of the kidneys by radiation does not have any contraindications, but there are still some precautions for its implementation. These include:

• age of children under 1 year;
• the presence of thrombosis and other cardiovascular diseases;
• overweight;
• taking psychotropic and sedative drugs.

It is worth remembering that these factors are not a list of contraindications; they only affect the reliability and accuracy of the results of the examination. The only contraindication is if the patient is allergic to the contrast agent or iodine. But even this will not be a problem, since hippuran can be easily replaced with a similar contrast.

Radioisotope examination of the kidneys is one of the most popular methods for accurately determining the condition of internal organs. Radioisotope methods are widely used today in various branches of medicine. The quality of information obtained with their help is much higher than from ultrasound, x-rays, MRI and CT. An important point is that during radioisotope research, radiation exposure to the body is 30–100 times lower. That is why it is considered safe for children.

Diagnostic device

Radioisotope diagnostics is carried out quite simply: a pharmacological drug is administered intravenously to a person, and a radiocirculographic installation registers the radiation at this time. Radioisotope diagnostics is divided into several areas, but in modern medicine Mainly two categories of methods are used. The first involves a quantitative assessment of data on the functioning of the kidneys (this includes radiometry and radiography). The second is scanning and scintigraphy, aimed at localizing (clarifying) the area of ​​kidney damage and obtaining a visual image of it.

Renography image

Isotope diagnostics not only shows the condition of internal organs, but also makes it possible to assess the level of kidney activity and promptly identify pathologies that begin in them. Renography is one of the types of radioisotope studies of the new generation, which uses hippuran, which belongs to the category of radiopharmaceuticals. It allows you to obtain images of affected organs where you cannot help ultrasonography. Radioisotope diagnostics involves calculating the amount of radiopharmaceuticals administered to the patient based on his body weight.

This type research based on unique property kidneys: they are able to selectively capture and direct hippuran to be excreted from the body. This quality, as well as the ability of hippuran to rapidly decompose, helps to minimize human radiation exposure during diagnostics. The level of radiation activity of a radiopharmaceutical is recorded externally at the time when the kidneys take hippuran from the blood through proximal parts tubules of the internal organ. After being in them, the substance is excreted from the body in as soon as possible without interfering with the functioning of the kidneys and other organs. Renogram is a recording of γ-radiation that is formed over the kidneys when hippuran is present in them. It is she who records all the changes that occur in the internal organs.

Medicine, nuclear physics and mathematics are components of the method

Without these components, there would be no isotopic study of the kidneys, which helps to identify and study pathologies in more detail. Renography has virtually no contraindications; there are only a few restrictions on its use. One of them is pregnancy, because even minimal radiation can negatively affect the condition of the fetus. Carrying out tests is also unacceptable if the expiration date of hippuran or another labeled drug has expired.

If necessary, radioisotope diagnostics are prescribed again, which happens in medical practice quite rare. This can happen if patients experience dynamic changes in the structure of their kidneys or there is a need to determine the effectiveness of the treatment method used. This type of examination does not require special isolation of the patient or transferring him to a special regime, which greatly simplifies the work of the medical staff.

During diagnosis, the patient should be in a sitting or lying position. The second option is used mainly for children and those in in serious condition adults. Special sensors are installed on the back opposite the organs being examined, the heart and bladder. To correctly place them at the level of the kidneys, patients often have to undergo x-rays before renography. The procedure itself lasts no more than half an hour.

Image analysis

Then specialists analyze the resulting renogram. To correctly decipher it and make a diagnosis, the radiologist uses mathematical analysis methods. High-precision calculations determine the level of cleansing functions of each kidney, the rate of filling of its vascular system, the time during which hippuran leaves the internal organ, and the characteristics of the accumulation of the radiopharmaceutical in the bladder.

Process safety

To people suffering various diseases kidneys, it is advisable to regularly perform renography. Isotope diagnostics is combined with x-rays. It can be performed several times without harm to the body, while x-rays can be performed once a year. The amount of radiopharmaceutical administered for research must be calculated taking into account age, general condition human health.

Storage safety precautions

In order for isotope diagnostics to be truly safe for patients and medical staff, it is carried out in rooms where the surfaces of floors, walls and ceilings are covered with special protective materials. Substances for renography are stored in underground lead-lined storage facilities. Hypurrane and similar radioactive preparations are prepared in fume hoods with lead-lined screens.

The room where isotope diagnostics are carried out is constantly monitored. The medical staff working there are undergoing training. The rooms in which renography is performed are located separately from medical departments, most often in the semi-basement parts of the building.

Not only its specialists, but also the employees of Gosatomnadzor, the sanitary-epidemiological service and other government agencies who supervise the structural unit are personally responsible for the level of radiation in the isotope department.

Rules you need to know

Undergoing any type of diagnosis requires the patient to follow certain rules, and renography is no exception. The study of the functioning of any of the internal organs will be as objective and high-quality as possible if the patient does not take food or medications before the tests. Be sure to remember: isotope (like any other) diagnostics and alcohol, drugs, psychotropic drugs incompatible.

There should not be any metal objects on the patient’s body during examinations. While the diagnosis is being carried out, the person remains motionless. If this point of the rules is violated, the examination results may be distorted and will not provide objective information about the condition of the internal organ being examined.

However, there are exceptions here: when examining the heart, whose activity is directly related to the kidneys, the patient may be asked to perform exercises on a walking track or a bicycle ergometer. Children under 3 years of age are not usually tested using radioisotope methods. When it turns out to be absolutely necessary, children are given sedatives.

This examination method is based on the ability radioactive isotopes to radiation. Nowadays, computer radioisotope research is most often performed - scintigraphy. First, the patient is injected with a radioactive substance into a vein, into the mouth, or by inhalation. Most often, compounds of the short-lived isotope technetium with various organic substances are used.

Radiation from the isotopes is captured by a gamma camera, which is placed above the organ being examined. This radiation is converted and transmitted to a computer, on the screen of which an image of the organ is displayed. Modern gamma cameras make it possible to obtain layer-by-layer “slices”. The result is a color picture that is understandable even to non-professionals. The study is carried out for 10-30 minutes, and all this time the image on the screen changes. Therefore, the doctor has the opportunity to see not only the organ itself, but also observe its work.

All others isotope studies gradually replaced by scintigraphy. Thus, scanning, which before the advent of computers was the main method of radioisotope diagnostics, is used less and less today. When scanning, the image of the organ is displayed not on a computer, but on paper in the form of colored shaded lines. But with this method, the image turns out flat and also provides little information about the functioning of the organ. And the scanning causes certain inconvenience for the patient - it requires him to be completely immobile for thirty to forty minutes.

Right on target

With the advent of scintigraphy, radioisotope diagnostics received a second life. This is one of the few methods that detects the disease on early stage. For example, cancer metastases in bones are detected by isotopes six months earlier than by x-ray. These six months can cost a person his life.

In some cases, isotopes are generally the only method that can give the doctor information about the condition of the diseased organ. With their help, kidney diseases are detected when nothing is detected on an ultrasound; microinfarctions of the heart, invisible on an ECG and echocardiogram, are diagnosed. Sometimes a radioisotope study allows the doctor to “see” thromboembolism pulmonary artery, which is not visible on x-ray. Moreover, this method provides information not only about the shape, structure and structure of the organ, but also allows you to evaluate it functional state, which is extremely important.

If previously only the kidneys, liver, gallbladder and the thyroid gland, now the situation has changed. Radioisotope diagnostics is used in almost all areas of medicine, including microsurgery, neurosurgery, and transplantology. In addition, this diagnostic technique allows not only to make and clarify the diagnosis, but also to evaluate the results of treatment, including constant monitoring of postoperative patients. For example, scintigraphy is indispensable when preparing a patient for coronary artery bypass surgery. And in the future it helps to evaluate the effectiveness of the operation. Isotopes identify conditions that threaten human life: myocardial infarction, stroke, pulmonary embolism, traumatic brain hemorrhages, bleeding and acute diseases organs abdominal cavity. Radioisotope diagnostics helps to distinguish cirrhosis from hepatitis, to discern malignant tumor at the first stage, identify signs of rejection of transplanted organs.

Under control

There are almost no contraindications to radioisotope research. To carry it out, an insignificant amount of short-lived isotopes that quickly leave the body is introduced. The amount of the drug is calculated strictly individually, depending on the patient’s weight and height and the condition of the organ being studied. And the doctor must select a gentle examination regimen. And most importantly: radiation exposure during a radioisotope study is usually even less than during an x-ray study. Radioisotope testing is so safe that it can be performed several times a year and combined with x-rays.

In case of an unexpected breakdown or accident, the isotope department in any hospital is reliably protected. As a rule, it is located far from the medical departments - on the ground floor or in the basement. The floors, walls and ceilings are very thick and covered with special materials. The stock of radioactive substances is located deep underground in special lead-lined storage facilities. And the preparation of radioisotope preparations is carried out in fume hoods with lead screens.

Constant radiation monitoring is also carried out using numerous counters. The department employs trained personnel who not only determine the level of radiation, but also know what to do in the event of a leak of radioactive substances. In addition to the department employees, the radiation level is monitored by specialists from SES, Gosatomnadzor, Moskompriroda and the Department of Internal Affairs.

Simplicity and reliability

The patient must adhere to certain rules during a radioisotope study. It all depends on which organ is supposed to be examined, as well as on age and physical condition sick person. Thus, when examining the heart, the patient must be prepared for physical activity on a bicycle ergometer or on a walking track. The study will be of better quality if done on an empty stomach. And, of course, you should not take medications several hours before the test.

Before the bone scintigraphy, the patient will have to drink a lot of water and urinate frequently. This flushing will help remove isotopes from the body that have not settled in the bones. When examining your kidneys, you also need to drink plenty of fluids. Scintigraphy of the liver and biliary tract is done on an empty stomach. A thyroid, lungs and brain are examined without any preparation at all.

Radioisotope testing may be interfered with by metal objects placed between the body and the gamma camera. After introducing the drug into the body, you must wait until it reaches the desired organ and will be distributed in it. During the examination itself, the patient should not move, otherwise the result will be distorted.

The simplicity of radioisotope diagnostics makes it possible to examine even extremely sick patients. It is also used in children starting from the age of three; they mainly examine the kidneys and bones. Although, of course, children require additional training. Before the procedure, they are given a sedative so that they do not fidget during the examination. But pregnant women are not subject to radioisotope testing. This is due to the fact that the developing fetus is very sensitive to even minimal radiation.

Radioisotope diagnostics of blood vessels allows us to identify pathological changes and the degree of vascular damage, the functions of many vital processes - the speed of blood movement, metabolism. Medical isotopes are produced thanks to nuclear reactors and radioisotope technologies. The administered drugs must have a short decay period so that specialists have the opportunity to obtain reliable test results when examining the characteristics of the genitourinary, of cardio-vascular system.

What kind of research is it?

Radioisotope diagnostics of blood vessels is a special test. Reflects the movement and distribution of labeled radioactive compounds in organs and tissues due to the introduction of radiopharmaceuticals into the body.

Specialists thus study the exchange of gases and substances, secretory excretory processes, and the speed of movement of lymph and blood through the vessels.

Radioisotope diagnostics is carried out in 2 options:

• screening - a test by taking blood from patients and then adding labeled substances to it to assess their interaction with each other;
• introduction of radiopharmaceutical drugs into the body for their subsequent movement in tissues and organs.

The essence of the study

The technique is based on the measurement and registration of radiation determined after introduction into the body certain drugs.

Changes in the body as isotopes are captured by heart cells are recorded on images taken in 3 planes.

In case of dysfunction muscle fibers the absorption of radioisotopes by cardiac cells begins to decline sharply.

Any of the administered contrast agents contains iodine, which, as it passes through the vessels, begins to be actively absorbed by the tissues, highlighting changes in the images. This allows doctors to clearly see the structure and structure of organs and identify changes that occur during cardiovascular pathologies.

Reference! When isotopes enter the body, they begin to emit rays, thanks to which the affected organ is illuminated.

Unlike conventional X-rays, isotopes can accumulate in the heart muscle, so specialists can even detect oncology and metastases, prostate cancer, myocardial infarction, cardiac ischemia, and coronary sclerosis in patients.

Radioisotope research makes it possible to understand when urgent surgery is necessary, for example, in case of severe damage to the biliary tract or liver.

Allows timely predictions in case of degeneration of hepatitis into cirrhosis of the liver.

The technique is carried out both in cases of suspected cardiovascular disease and in cases of already established preliminary diagnosis to obtain an assessment of the effectiveness of the therapy and clarify the degree of vascular damage.

One of modern methods computer radioisotope scintigraphy is considered diagnostic, during which special detectors located at a certain angle begin to register radiation when isotopes are administered intravenously.

The information received is displayed on a computer monitor, with a three-dimensional picture at once, rather than a flat image of the affected organ.

Indications

Radioisotope research allows:

• assess the condition of organs in case of damage (trauma);
• identify chronic and acute diseases;
• identify disturbances in the structure of blood vessels caused by diseases of neighboring organs;
• determine a malfunction in the hematopoietic or urinary system.

The main reasons for performing isotropic vascular studies are:

• failure of digestive functions;
• gland diseases internal secretion, cardiovascular and circulatory system;
• damage to the lungs and urinary organs.

Radioisotope methods for studying veins and blood vessels are applicable in many areas of medicine:

• hematology to determine anemia, life expectancy of red blood cells;
• gastroenterology to study the functions, size and location of the gastrointestinal tract, liver, spleen;
• cardiology to monitor the movement of blood through the cavities of the heart and blood vessels, giving an opinion on the state of the myocardium, taking into account the nature of the distribution of the injected contrast agent into affected or healthy areas;
• neurology to determine the location, extent of spread, nature of the brain tumor;
• pulmonology to listen to the breathing of the lungs.

The note! Radioisotope techniques are widely used in oncology. Injected radionuclides have the ability to accumulate in the tumor. This allows doctors to detect cancer of the lungs, pancreas, central nervous system early stage even in the case of localization of small tumors.

Children are diagnosed in a radioisotope laboratory if other research methods become uninformative. For example, in order to detect kidney diseases at an early stage, also in cases of existing renal failure.

Contraindications

The resulting radiation dose for patients during the procedure is insignificant, therefore special contraindications does not exist.

Although the limitations are known:

• pregnancy;
• children under 3 years old;
• individual iodine intolerance.

The distortion of the results may be affected by the use of psychotropic drugs by patients to reduce blood pressure before the study.

In order to protect themselves in every possible way from unnecessary examination, during the procedure, patients must stay in a special booth covered with protective panels.

To avoid the spread of radiation throughout the room contrast agents stored in special cabinets.

Reference! Many people are concerned about the safety of radioisotope diagnostics, because it is known that administered radioisotope drugs have a certain degree of radioactivity, causing confusion, fear and anxiety. Doctors are trying to reassure, dispel myths and evaluate all possible pros and cons before conducting a radioisotope study.

Unlike conventional X-rays, the radiation dose during radioisotope research is almost 100 times less. This makes it possible to carry out the technique even for newborn babies.

Decoding the results

Already 5-7 minutes after the introduction of isotopes into the body, their highest concentration is observed in the affected area.

After 25-30 minutes, the concentration begins to gradually decrease. After 30-35 minutes - sharply, 3-4 times.

For getting reliable results During this period, doctors need to scan the vessels under study and other nearby areas, when the boundaries of the structures, their location and functioning are clearly and visually visible.

If it leaks pathological process, should appear in the picture dark spots.

Radioisotope research is carried out only in certain clinical situations when, in the opinion of doctors, it allows one to give all the answers to questions, and the benefits of the study are much higher than the potential harm from isotropic radiation.

To give a detailed assessment of the obtained images, the technique is often carried out in combination with an x-ray.

Interesting video: radioisotope diagnostic method