Uzdg of the renal arteries. Ultrasound of the renal arteries - a research technique. The main differences between the ultrasound of the vessels of the kidneys and the ultrasound of the renal arteries

The normal functioning of the kidneys, which depends on the blood supply, largely determines the general condition of the human body. In this paired organ, toxins are cleansed, hormones and substances are synthesized that regulate blood pressure (renin) and the number of red blood cells (erythropoietin). The renal arteries depart directly from the aorta, the largest vessel with high pressure and blood flow velocity of up to 50 cm/s. Changes in this segment significantly affect the functioning of the kidneys. To diagnose violations of the delivery of nutrients and oxygen with the blood, the duplex scanning method is used.

What is the diagnostic method

Duplex scanning of the renal arteries is an ultrasound method for diagnosing hemodynamic disorders in the vessels that feed the kidney tissue using the Doppler effect.

To study the anatomical structure of the kidneys, "B-mode" (from "brightness" - brightness) is used: in a two-dimensional image, different tissue densities are visualized in grayscale. The result of the study is high-frequency ultrasonic waves registered by a special sensor, which are reflected from the organs.

The visualization of moving objects is based on the frequency difference of the reflected signals. Depending on the direction of movement of the object (in duplex scanning, these are erythrocytes, red blood cells), the image becomes colored. As the particles approach, the signal becomes more frequent and a red image is displayed on the cartogram. Waves with lower rates form blue.

In addition, there are different types of blood flow:

• Laminar ("irrotational") - the entire volume moves in the same direction at the same speed. The image is represented by a uniform blue or red color.
• Turbulent ("chaotic") - a kind of mosaic of blue, red and sometimes purple is visualized on the screen, formed by the multidirectional movement of erythrocytes.
• Mixed version - a combination of the previous types in one vessel, in its different parts.

To conduct an examination, you only need an ultrasound machine and a specialist who will highlight the changes and analyze the results using a computer program.

Indications and contraindications for the study

Violation of the blood supply to the kidneys can be caused by both local and generalized pathological processes in the body. However, all nephrological diseases have common symptoms, in the presence of which duplex scanning is indicated, described below.

• Renal colic is an acute pain syndrome that occurs in the lower back and is transmitted to the external genital organs and the inner surface of the thigh. It occurs due to increased fluid pressure inside the pyelocaliceal system of the kidneys (most often with urolithiasis in violation of the outflow of urine due to a stone in the ureter).
• Hematuria (from "haem" - blood and "uro" - urine). A symptom that often leads patients to seek medical attention. The presence of blood in the urine with the color of the latter in pink or bright red. This condition can be caused by trauma, taking toxic medications, inflammatory diseases of the kidneys.
• Low back pain accompanied by changes in urinalysis or with the exclusion of neurological pathology (for example, radicular syndrome).
• Arterial hypertension is a persistent increase in pressure more than 140/90 mm Hg. Art. There is a vasorenal mechanism for the development of the disease. In violation of the blood supply to the kidneys, they synthesize a large amount of biologically active substance - renin. This hormone triggers a cascade of reactions that stimulate an increase in systemic blood pressure.
• Edema. The mechanism of their development is a violation of the filtration capacity of the kidneys and the accumulation of fluid in the tissues.
• Diabetes. With this pathology, vessels of all calibers are affected, impaired functioning of the renal arteries can lead to chronic insufficiency, which requires regular hemodialysis.
• Kidney pathologies: glomerulonephritis (inflammatory disease with damage to the glomerular system), nephroangiosclerosis (damage to small renal vessels), nephropathy (diseases of uncertain origin that disrupt filtration and reabsorption in the tubular system).

In addition, the method is used to diagnose congenital anomalies of the kidneys (for example, L- or S-shaped kidney), to assess the condition before and after surgery.

A contraindication to the study may be an acute mental illness of the patient or the inability to be in a horizontal position (for example, after a spinal injury). In the presence of multiple organ (cardiovascular, respiratory, hepatic) insufficiency, which require hardware life support, duplex scanning is postponed until the condition stabilizes.

How to Prepare for a Duplex Scan

Ultrasound diagnostic methods do not require special preparation of the patient. However, in the presence of increased gas formation in the intestine, the image may be distorted. Therefore, doctors advise to adhere to some simple rules:

• 2 days before the scan, it is not recommended to eat raw fruits, legumes, potatoes, cabbage, pastries from premium flour, sweets, cakes and other confectionery.
• On the day before the study, take enterosorbents: White coal, Smecta, Polysorb.
• If possible, scan in the morning on an empty stomach.

Doctor's advice! If the study is scheduled for the afternoon, it is acceptable to take a light breakfast at least 6 hours before the study

How is the study going

Duplex scanning of the renal arteries is performed in the ultrasound room of a polyclinic or a private medical center.

The patient should remove all clothing up to the waist, as well as accessories that may interfere with the movement of the probe. Depending on the condition and features of the anatomical structure of the kidneys, the patient is located lying on the couch or standing next to the ultrasound machine.

Before the study, a special gel is applied to the sensor, which prevents the formation of an air space between it and human skin.

Important! The presence of gas (air outside or inside the intestine) interferes with the passage of ultrasound waves, distorts the image and can cause false results.

Switching modes, the doctor first examines the structure of the vessel, the evenness and clarity of the contour of the wall, the diameter and the presence of formations inside the lumen. When Doppler (D-mode) is selected, a moving color image appears on the screen, which may be accompanied by a slight noise (the sound of blood moving through the vessels). During the study, the linear and volumetric velocity, the presence of an abnormal direction of blood flow are determined.

The duration of the procedure is from 15 to 30 minutes. After the doctor takes the sensor, the patient wipes off the remains of the gel from the skin, gets dressed and can go home.

The results of the study, presented in the form of a conclusion, images on special thermal paper or on digital media, are issued immediately after the completion of the diagnostic manipulation.

Advantages of the method and possible complications after the study

Diagnosis of disorders in the renal vascular system involves the study of the cause, location and severity of the lesion. For this, ultrasonic (duplex scanning) and radiological (angiography and excretory urography) methods are used.

Comparative characteristics of studies are presented in the table.

Important! For all studies that require the introduction of a contrast agent, a preliminary allergic test is mandatory.

Duplex scanning, like all ultrasound diagnostic methods, is the safest study of the circulatory system, which does not cause undesirable consequences.

How to decipher the results

The duplex scanning method combines the study of the morphological structure of the kidney and the features of blood filling. An ultrasound specialist evaluates the following indicators:

• Location, shape and size of the organ.
• Thickness and uniformity of the cortical and medulla.
• Deformities of the pyelocaliceal system.
• The presence of neoplasms.
• The structure of the "renal gate": features of the location of the renal artery, vein and ureter.
• The length and diameter of the vessels. Normally, the length of the renal artery is from 2.5 to 6 cm with a lumen diameter of 0.2 to 0.7.
• The presence of intravascular formations: blood clots, atherosclerotic plaques.
• Blood flow velocity (cm/s) and resistance index, which indicates the resistance created by the vessels.

With congenital anomalies, variable placement of vessels is observed depending on the shape and location of the organ: horseshoe-shaped, L- or S-shaped kidney.

The presence of obstacles to the free movement of blood on the scan is displayed by an increase in the resistance index, an increase in linear and a decrease in volumetric velocity, and a characteristic turbulent blood flow.

This method is widely used to clarify the localization, length and shape of vessels before surgery, as well as to evaluate the effectiveness of the latter. The absence of undesirable consequences and contraindications allows us to consider duplex scanning of the renal arteries as the method of choice for children and pregnant women.

The anatomical structure and movement of blood in the renal artery system during duplex scanning are presented in the video below.

The supplemented and modified method of ultrasound diagnostics, based on the Doppler effect, allows you to study the blood flow velocity and the state of the arteries. This procedure is called Dopplerography (UZDG), and is performed to identify pathological processes in organs that have arteries and vessels.

Dopplerography of the vessels of the kidneys determines the state of health of the vessels and veins responsible for the proper functioning of the organ. The Doppler effect is the difference between the frequencies of an ultrasonic pulse sent to an organ and the response echo signal reflected from red blood cells (erythrocytes).

The research data is transmitted to a computer monitor and decoded by a medical specialist. There is spectral dopplerography and visualization. The first conveys an assessment of the state of blood flow in the form of a curved line, the second - in the form of a visual picture in color or black and white.

The color resolution of indicators, otherwise color Doppler mapping (CDC) is more informative, since, in fact, it eliminates errors in diagnosis. The red color on the monitor shows the blood flow directed to the sensor, the blue color shows the movement of blood flow away from the sensor. The brightness of the color is determined by the speed of the blood flow process.

Since the traditional ultrasound of the kidneys allows to assess only the qualitative health of the organs themselves, an ultrasound of the kidneys with Dopplerography is used to make an accurate diagnosis. The double study is deeper, the specialist has the opportunity to study the organ itself, the speed of blood flow and the state of the vessels.

The combination of ultrasound with Dopplerography or duplex of vessels determines the pathology at an early stage of its development, when the patient does not complain about symptoms.

Diagnostics

Duplex scanning of the renal arteries reveals the presence of atherosclerotic growths, blood clots, and expansion of the vessel walls (aneurysm). According to Doppler, narrowing of the lumen of arteries, veins and vessels (stenosis) and other parameters of damage to the vascular walls are diagnosed.

Ultrasound of the kidneys allows you to differentiate a cancerous neoplasm from a benign tumor. Assess the state and structure of the cellular elements of the kidneys that perform a specific function (parenchyma). Determine the presence of kidney stone disease. During pregnancy, using a Doppler study, a low oxygen content in organs and tissues (hypoxia) is diagnosed in the unborn child.

Inspection of the state of the renal vessels can be performed from several accesses

Cases of appointment of dopplerography

A study of the vessels of the kidneys and the organ itself by means of Doppler sonography is carried out on the basis of the identified symptoms, in order to confirm or refute the initial diagnosis, as well as to identify in more detail the causes of an existing pathology.

The main indications for the appointment of ultrasound of the vessels of the kidneys are:

• regular pain in the lumbar spine, not associated with muscle overload;
• pain associated with impaired bladder emptying;
• abnormal indicators of laboratory tests of urine (leukocytes, blood, protein);
• hypertension of the 2nd and 3rd stage;
• exacerbation of the chronic course of any kidney disease;
• endocrine disruptions;
• the assumption of the presence of neoplasms;
• suspicion of pathological changes in blood vessels;
• preoperative examination period;
• pathology during pregnancy;
• post-traumatic pain.

Diagnostic measures are carried out on an outpatient basis, do not cause discomfort, have no contraindications, and are safe for health. In the case when the ultrasound scan did not reveal any abnormalities, and the symptoms continue to develop, an MRI (magnetic resonance imaging) or CT (computed tomography) of the kidneys is prescribed. This may be due to the only drawback of the Doppler method - the inability to study small vessels.

Activities before dopplerography

Objective ultrasound results are possible if certain rules are followed before the procedure. Preparation is simple, but necessary. Most often, the study is scheduled for the morning hours.

The obligations of the patient before the procedure are as follows. At least 48 hours before the procedure, unload the diet.

Exclude dairy and sour-milk products, any pastries (including bread), raw vegetables, fruits, peas and beans, soda, sweet foods and drinks. This diet is necessary to reduce flatulence in the intestines. For the same purpose, medicines are taken, such as Espumizan, activated charcoal (two tablets in the morning and before bedtime).

It is important not to take food and water from the evening before the scheduled study. Doppler ultrasound of the kidneys is not performed after any other examinations of the digestive system, as well as in violation of the skin (wounds, ulcers, burns) in the area being examined.

The order of the ultrasound

The procedure is performed in the initial position lying on your side. Having freed the torso from clothing, the patient is located on the couch. The doctor evenly moves a special sensor connected to the main ultrasound machine over the patient's body. Ultrasonic waves emanate from the device, which, upon contact with red blood cells, are reflected, converted into electrical impulses and displayed on the monitor.

To facilitate the sliding of the sensor over the skin, the latter is lubricated with medical gel

Unusual sounds that may accompany the advance of the transducer convey blood flow readings. Uniform sounds should not cause concern. A piercing energetic sound determines the area with pathological changes. The time interval for Doppler ultrasound is determined by 25-30 minutes. Post-procedure activities are not provided.

Decoding results

Doppler ultrasound results are sent to the attending physician, who deciphers the information. The obtained indicators are compared with the standards, and the doctor diagnoses a particular kidney disease.

Normally, the values ​​of ultrasound of the renal arteries fit into the following digital range

The contours of the organs should be even. The difference between one kidney and another in size is allowed no more than two centimeters. In the process of breathing, the kidney does not move more than 2.5 cm. In addition, the specialist evaluates the shape and echo density of organs, the anatomical structure and location of veins and arteries, the vascular system as a whole, the adrenal glands, the location of the kidneys relative to each other and other parameters.

Prerogative aspects of Doppler ultrasound

The advantages of using this research method are as follows:

• pathological changes in the kidneys do not have age criteria, ultrasound of the renal vessels is allowed to be performed at any age;
• the method is not invasive, that is, there is no direct intervention in the patient's body;
• it is possible to assess the state of kidney health immediately after the study;
• dopplerography is not a rare or inaccessible diagnostic method;
• UZDG does not require a lot of time.

At the present stage of development of affordable medicine, dopplerography is a prerogative diagnostic technique for renal diseases. A timely procedure diagnoses the disease at the beginning of its development.

Ultrasound of the kidneys- a diagnostic procedure, during which, using high-frequency sound waves, the structure, size and location of the kidneys are visualized. The results make it possible to identify urolithiasis, tumors and cysts, purulent lesions, anomalies in the development of a paired organ. Ultrasound of the kidneys is carried out as an independent study and in combination with ultrasound of the adrenal glands, bladder, dopplerography (duplex and triplex scanning) of blood vessels. The cost depends on the scope of the study and the modes used, it is highest for renal ultrasound with visualization of blood vessels.

Training

Preparation for ultrasound of the kidneys should begin a few days before the procedure. Compliance with all the rules allows you to minimize the risk of interference in the path of ultrasonic waves, get a clearer image and reliable results. The training program includes the following activities:

• Diet correction. For 3-4 days before the study, you should follow a diet that excludes the use of foods that increase gas formation. Under the ban are spicy, fatty and fried foods, confectionery, rye bread, cabbage, legumes, dairy products.
• period of famine. Ultrasound is best performed on an empty stomach. The optimal break in eating is 8-12 hours. If the procedure is carried out during the day or in the evening, it is permissible to eat dried white bread, fish, meat, reducing the time of hunger to 5-6 hours.
• Reception of enterosorbents. 1-1.5 hours after the last meal, it is recommended to take an enterosorbent, for example, activated charcoal. With increased gas formation, carminative preparations should be used.
• Drinking water. If the bladder is examined with ultrasound diagnostics of the kidneys, then an hour before the scan, you need to drink half a liter of water without gas, do not urinate until the end of the procedure.

What shows

Ultrasound of the kidneys is used to determine the location, number, shape and size of organs. The diagnostician evaluates the nature of the contours, the structure of the parenchyma, the presence or absence of neoplasms, stones. When scanning the kidneys and adrenal glands, in addition to the parameters described above, the structure and size of the adrenal glands are visualized, the presence of hyperplasia, inflammation, hematomas, and tumors is diagnosed. The kidneys together with the bladder are examined if nephrolithiasis is suspected: the result reflects the structure and functioning of these organs, their interaction. Ultrasound of the kidneys together with dopplerometry reveals the characteristics of the blood flow of the vessels of the kidneys.

In healthy people, the kidneys are shaped like beans, the left organ is located slightly higher than the right one, the outer contours are even and clear. The parenchyma has a homogeneous echogenicity. Normal blood flow is visualized in dark colors, its speed is 50-150 cm/sec. With the help of ultrasound diagnostics, the following pathologies are detected:

• Urolithiasis disease . Kidney stone disease is accompanied by the formation of stones that look like echo-positive formations. Inclusions with a diameter of 4 mm or more are clearly visualized. The urinary tract is dilated. With microcalculosis, sand, small stones are determined.
• Nephroptosis. Excessive mobility of the kidneys leads to their displacement - nephroptosis. The omission of the right organ is more often diagnosed, less often - the left, extremely rarely - both. With a displacement of one and a half vertebrae, I degree of the disease is determined, for 2 vertebrae - II degree, for 3 or more vertebrae - III degree.
• Kidney neoplasms. Fluid-filled cysts, abscesses, and hematomas appear as areas of low echogenicity (shadowing). The density of tumors is determined by their type, but always differs from the echo density of the renal tissue.
• Pyelonephritis. The characteristic signs of pyelonephritis are an increase in the size and limitation of the mobility of the kidneys, an uneven contour, and a thickening of the tissue with a light shade.
• Lack of function. An increase in the echogenicity of the parenchymal tissue, uneven contours, and a decrease in blood flow rate indicate renal failure.
• Glomerulonephritis. The diagnosis of glomerulonephritis is confirmed by a decrease in the size of the kidneys, increased tissue density, displayed in a lighter color.

Any diagnostic study, including ultrasound, is not interpreted in isolation and cannot serve as the only criterion for a proposed diagnosis. The results confirm the assumptions of the urologist made during the clinical interview of the patient, examination, and obtaining the results of blood and urine tests.

Advantages

The advantages of ultrasound are the absence of contraindications to the procedure, its painlessness, availability. The study is carried out on infants, pregnant women, elderly and old people, seriously ill patients. Compared to kidney MRI, CT and radiography, ultrasound diagnostics has a lower cost, even with a comprehensive examination, including vascular Doppler. However, the accuracy of the data is insufficient: it is not always possible to establish the location of the kidney, the nature of the neoplasm, and to identify the presence of small inclusions.

Ultrasound is one of the most informative and at the same time safe examination methods that allow assessing the condition of internal organs. Over time, research technology was enriched with new methods, which significantly expanded the scope. Doppler ultrasound of the kidneys and blood vessels is one of such new methods.

Ultrasound of the kidneys and renal vessels with dopplerography

It is no secret that the functionality of many organs can be assessed not so much by the state of the tissue, but by the state of the arteries and veins serving the organ. This is quite natural: after all, an organ or tissue receives nutrition and oxygen only with blood. The task of examining blood vessels is solved by dopplerography.

This method refers to ultrasound based on the Doppler effect. Its essence is as follows: the examined area is irradiated with ultrasonic waves. When a motionless reflecting body is detected, the reflected wave - an echo signal, has the same frequency as the original one. When meeting moving objects, the frequency of the reflected wave changes: it becomes larger if the moving body moves towards the sensor or smaller if it moves away from it. This change between the initial ultrasonic pulse and the reflected signal is called the Doppler shift.

The difference between the frequencies of the initial and reflected waves depends on the speed of movement. Well, the moving objects in the study are red blood cells. It is on the speed of their movement that the method is based, which allows to accurately assess the state of the blood vessel, filling, flow density, speed, and so on.

There is spectral and imaging ultrasound dopplerography.

• Spectral - during the examination, the intensity, frequency of the echo signal is fixed, and a curve is drawn based on these data. It gives an idea of ​​the distribution of velocity in the blood flow and the direction of movement in the vessel.
• Visualization - the same data is interpreted as a visual image of blood flow parameters. This method is more visual and allows you to study the state of several organs and vessels. There are duplex Dopplerography - a two-dimensional image in black and white, and color - with color Doppler mapping.

results

The functionality of the kidney depends on the state of blood flow. And even in cases where the kidney tissue itself is not damaged. Doppler ultrasound of the kidneys and blood vessels allows you to find out the following factors:

• the level of damage to the walls of blood vessels and arteries in thrombosis, atherosclerosis, etc.;
• the presence of blood clots or atherosclerotic plaques;
• blood circulation parameters: blood volume, flow rate, velocity distribution;
• the size of the vessels, which allows to identify stenosis, spasm;
• the size of the organ, shape, uniformity or heterogeneity of the structure;
• the structure of the parenchyma;
• violation and cause of microcirculation disorders.

According to the state of the vessels and their performance, it is possible to assess not only the current state of the organ, but also the effectiveness of treatment, therefore Doppler ultrasound is performed not only during diagnosis, but also during treatment.

Indications

The reason for the appointment of a Doppler examination is both established pathologies and certain symptoms indicating a particular diagnosis. These include:

• pain and discomfort in the lumbar region, which are permanent;
• any degree of severity;
• limbs, face;
• blood, protein, increase in the number of leukocytes in the urine;
• disorders of cardiovascular activity, especially against the background of increased diastolic pressure;
• bruises and injuries in the lumbar region, as they are fraught with damage to blood vessels;
• hypertension of any origin;
• acute and chronic forms of renal ailments or the genitourinary system - in the latter case, an examination of the bladder is usually also prescribed;
• endocrine disorders - vasculitis, diabetes mellitus;
• late toxicosis during pregnancy;
• suspected tumor;
• vascular diagnostics - to determine congenital and acquired anomalies;
• assessment of the state of vessels and organs after transplantation of a kidney or other organ.

There are no contraindications for the examination. However, it should be borne in mind that the state of small vessels is difficult to assess in this way.

Preparation for the procedure

Dopplerography requires preparation. The fact is that the state of the intestine, and, more precisely, the presence of gases here, greatly complicates the study.

In fact, all preparation comes down to eliminating or minimizing this phenomenon:

• 2-3 days before the examination, the patient must follow a diet that excludes all foods that cause increased gas formation. These are cabbage in all forms, bakery products - white crackers, legumes, raw vegetables and fruits, sweets, especially chocolate, coffee and carbonated drinks are allowed. As a rule, milk and dairy products are excluded, as quite a few people do not absorb this product very well.
• To reduce gas formation, especially with a tendency to this, activated charcoal, sorbek, espumizan are prescribed - 2 tablets 1-3 times a day, depending on the condition and well-being.
• The procedure is performed on an empty stomach: eating and drinking 8-12 hours before the examination is prohibited, so the examination is almost always carried out in the morning. If the procedure is scheduled for the afternoon, a light breakfast is allowed, but no later than 6 hours before the ultrasound.
• Do not take medication before the examination. An exception is made for patients whose treatment requires constant medication: diabetes mellitus, arterial hypertension, coronary artery disease, and so on.

Doppler ultrasound of the kidneys is not allowed after fibrogastroscopy or colonoscopy. With such an examination, gases charmingly enter the intestines, which makes Dopplerography almost impossible.

Execution Method

The procedure itself is not difficult:

1. The patient undresses to the waist, removes jewelry, if there is any in the area under study, and lies on the side of the couch.
2. The doctor applies a special gel to the sensor, which ensures the tightest possible contact between the skin and the sensor.
3. The specialist moves the sensor over the area in the projection of the location of the kidneys. In this case, the device emits ultrasonic waves of a certain length. The signal, meeting with a movable obstacle - blood erythrocytes, is reflected with a different frequency. The reflected wave is captured by the sensor and converted into electrical impulses.

The latter are already converted by the device itself and visualized in graphical form or as a color image. The image is dynamic, which allows you to evaluate the movement of blood through the vessels in real time and fix any deviations from the norm.

For example, the circulation velocity in the main renal arteries ranges from 50–150 cm/s. With stenosis, when the working channel is reduced by 70-80%, the blood flow rate increases markedly, and then drops sharply. In the image, the accelerated circulation is colored brighter, while the slow circulation is paler. In addition, the device captures and displays turbulence in the artery.

During the procedure, a two-dimensional image of the area being studied is created on the screen. The doctor fixes the necessary parameters in the image. The data is reflected in the completed document.

The whole procedure takes no more than 30 minutes and is completely painless.
On the video, dopplerography of the renal vessels:

Norms

The result of ultrasound is a research protocol that includes all the parameters necessary for assessing the condition:

• shape - normally, the kidney should have a bean-shaped shape;
• the contour of the organ should be clear and even;
• the size of the kidneys must match, a difference of no more than 2 cm is allowed;
• the structure of the capsule is hyperechoic, that is, it strongly reflects ultrasonic waves, the thickness of the capsule is up to 1.5 mm;
• the echo density of the renal sinus and perirenal tissue should be equal;
• the echo density of the pyramids is normally lower than that of the parenchyma;
• the right kidney should be slightly lower than the left;
• when breathing, the kidney is displaced by 2-3 cm, no more;
• anteroposterior size - up to 15 mm;
• resistance index of the main artery - the difference between systolic and diastolic velocity in relation to the maximum systolic blood flow velocity, should normally be: 0.36–0.74 in the interlobar arteries and 0.7 in the gate area;
• anatomical arrangement of arteries and veins;
• the state of the vascular wall - normal thickening, ruptures, aneurysms, thinning should be absent;
• vessel lumen - for the main trunk, for example, the norm is 3.3-3.6 mm, for the interlobar artery - 1.4-1.6 mm, for the segmental - 1.9-2.3 mm and so on. 5 renal arteries are obligatory examined;
• assessment of the state of the adrenal glands and perirenal tissue;
• resistance index - measured at 3 points: in the final, middle and proximal section of the arterial vessel. A significant difference between the data in the kidneys indicates a violation of blood circulation.

Doppler ultrasound data cannot be considered absolute. The method allows you to assess the state of up to 90% of the vessels of the kidney, but not everything can be fixed. But even in this case, ultrasound is one of the most informative and important diagnostic methods that exist today.

With the help of ultrasound examination of the vessels of the kidneys, it is possible to detect serious pathologies in real time. With the help of such a diagnostic measure, the position of these vessels is determined, their physiology is assessed. It is also important to consider their location relative to the kidney and determine the diameter, as well as identify possible obstacles to normal blood flow.

What methods are used to examine the renal arteries?

The following common methods are used:

1. UZDG - ultrasonic dopplerometry. This method works on the basis of the Doppler effect, in which ultrasound waves are able to be reflected from movable objects, which are blood cells.
2. duplex scanning. This method opens up the possibility of assessing not only the speed of blood flow, but also the chance to consider the anatomy of each vessel. This technique is advanced and will help to determine the entire spectrum of vascular pathologies, regardless of their level of development. This method makes it possible to find out the structure and caliber of the vessel, all the functional components.
3. Triplex scanning, it is also called color Doppler mapping or CFM. This method is similar to dopplerometry, but there is still an overlay of color blood flows on a two-dimensional image.

The most effective at the moment is a comprehensive study of blood vessels by all methods. This is the only way to get complete and reliable data with clear visualization. Pathologies can be detected at the initial stages of development, which will simplify their treatment. At first, it is often asymptomatic. The harmlessness of such a procedure allows you to monitor the state of the arteries in dynamics and track all changes.

The essence of the CDC procedure

Color Doppler mapping is a method that makes it possible to assess blood flow in the vessels. The basis of the study is a combination of a two-dimensional image and an assessment of blood flow in accordance with Doppler indicators.

The diagnostician displays an image familiar to ultrasound, and in the place that is being studied, blood flows and, accordingly, their speeds are represented in color. The following colors will be visible on the monitor:

• Red streams are blood that is moving towards the sensor.
• Blue streams - blood that follows from the sensor.

The speed can be judged by the intensity of the color, the less pronounced it is, the slower the flow moves. The color flow method not only displays a visual picture, but also analyzes the direction, speed, and nature of the blood flow. The patency of the kidney vessels, their diameter, and resistance are also examined.

Using this method, you can install:

• Is there a thickening of the vessel wall.
• Are there blood clots?
• The presence of atherosclerotic plaques.
• crimp.
• Excessive expansion of the lumen of the vessel - aneurysm.

When is a renal artery examination scheduled?

The main reason for the appointment of a Doppler study of the vessels of the kidneys is the suspicion of a violation of the inflow and outflow of blood to the organ. In the course of diagnosis, it is possible to subdue the causes of this, the form of the anomaly. The patient is sent for an additional study of the kidneys, if a pathology is detected during a routine ultrasound of the organ. Also cases of appointment are related to:

1. Impaired and/or painful urination.
2. The patient has swelling of the eyelids of the face in the morning.
3. There are pain sensations in the lumbar region, while they are not related to diseases of the spine.
4. With persistent hypertension.
5. If organ failure is suspected.
6. If tumors of the kidneys and adrenal glands are diagnosed.
7. If necessary, study the circulatory system that provides the vital activity of the tumor.
8. If necessary, track the dynamics of treatment.

As for contraindications, there are no absolute ones. The only thing, if there is no need for urgent surgical intervention, then the study is carried out after FGDS and colonoscopy. After all, during these procedures, a large amount of air is launched into the intestines, which will become an obstacle for vascular diagnostics.

It is impossible to implement this method if there is an opening of a wound or burns at the location of the sensor for diagnostics.

Preparation measures and scheme of conduct

Long and large-scale preparation is not needed, but several steps should still be taken in order for the results to have high reliability and accuracy. Main steps:

1. 3 days before the study, you need to go on a diet. At the same time, fatty foods, smoked meats, cabbage and legumes in any form, carbonated drinks should be excluded from the menu.
2. You can eat steamed porridge, vegetables, meat and fish during the preparatory period.
3. In the course of preparation, it is also worth taking sorbents, in accordance with the instructions.
4. If there are problems with flatulence, then it is also necessary to include enzyme preparations in the intake.
5. Before the study in the evening you need to have dinner no later than 18:00.
6. Also in the evening you need to do a cleansing enema and take activated charcoal at the rate of 1 tablet per 10 kg of weight.
7. The procedure is performed on an empty stomach, so you can not have breakfast in the morning.

If the patient has hunger pains or other severe pathological conditions, then it is allowed to eat no later than 3 hours before the procedure.

It is carried out according to the standard scheme. The patient frees the area under study from clothing, lie down on his side. A gel is applied to the skin, and a study is carried out.

Norms and pathologies

During the diagnosis, vascular pathologies can be detected. They are determined by comparing the norm with the data obtained. With the protocol of the study, you need to go to the attending physician, he will be able to decipher the data and prescribe treatment if necessary.

Conclusion. The combination of several methods in the study of renal vessels is considered the most effective and effective method that allows you to identify pathologies at the very beginning of its development. Regular preventive examination for risk groups is mandatory.