An examination, including ultrasound of the vessels of the kidneys, is aimed at recognizing the features of the location of veins, arteries and their diameter. This diagnostic method allows you to determine the speed of blood flow. This happens due to the work of the Doppler effect, an Austrian physicist, whose name became the basis for the name of a specific procedure - Dopplerography of the vessels of the kidneys.
In certain cases, it is required to undergo an ultrasound examination of the vessels of the kidneys to obtain a picture of the blood flow in the organ.
The essence of the method
The method of ultrasound examination of the kidney vessels is based on ultrasonic waves that are reflected from the erythrocytes present in human blood. After their reflection, the waves are recorded by a special sensor of the main apparatus and converted into electrical impulses. Only after that, the doctor can study the overall picture of the state of the body.
All converted pulses are displayed on the monitor of the device in graphic format and color photographs. They give a detailed idea of the state of the bloodstream. The main feature of this research method is the ability to monitor the activity of the organ and its surrounding vessels in real time.
What does a duplex scan of the renal arteries show?
Doppler ultrasound of the renal arteries guarantees the ability to follow the blood flow during spasm, any narrowing or even thrombosis. Correctly conducted analysis contributes to the compilation of a picture of possible pathological processes during the onset of the disease. The study will be especially useful in cases where the disease is asymptomatic due to an early stage or after a series of therapeutic measures to confirm the emerging dynamics of the patient's recovery. Painless duplex scanning of the renal arteries also helps in assessing:
- architectonics of the problem area (structure, type, location and volume of the affected area);
- functionality (an indicator of blood resistance).
Advantages and disadvantages
The main positive quality of ultrasound of the renal arteries using a Doppler transducer is the ability to immediately upon completion of the examination to get the result at hand along with the initial interpretation from the specialist conducting the examination. At the same time, the final diagnosis to the patient should still be made by the attending physician after studying the results obtained and on the basis of incoming complaints from the person who applied.
Ultrasound of the kidney vessels according to the Doppler principle does not have injections, which is very comfortable for the patient. The method based on the Doppler effect does not provide for any injection interventions, which makes it comfortable for the patient, as safe and painless as possible. In addition, this option for studying the problem is listed as a relatively budget version of execution against the background of other variations in the context of visualizing a possible disease.
From the point of view of the effect on the body, the kidney doppler has no contraindications, since ionizing radiation is not used in its work. According to experts, it is unlikely that it will be possible to cope with the study of soft tissues more effectively, because even the most advanced X-ray machine is not capable of producing a clear picture of the vascular network. It is much more convenient to involve an angiography of the organ with Doppler, which will confirm the preliminary diagnosis, or refute the presence of problems in the kidney.
Indications for research
Doppler ultrasound is prescribed by the attending doctor with numerous suspicions, since it is with its help that a number of both newly formed pathologies and chronic diseases that do not allow a person to feel full for many years can be identified. The most common reasons for scheduling a Doppler scan are:
- colic;
- discomfort in the lumbar region;
- swelling;
- diseases of the cardiovascular and endocrine direction;
- toxicosis in pregnant women in the later stages;
- chronic diseases that are associated not only with this organ, but also with the bladder (used to confirm whether it is normal).
Diagnosis can be made even in children who are suspected of having vesicoureteral reflux. If one of the parents has problems in the kidney part, then the kids will be sent for examination to exclude all possible anomalies from this area, which are transmitted at the genetic level from mom or dad.
Preliminary preparation
If the patient wants to get the most correct answer on the analysis, he will need to carefully prepare, starting with getting rid of the constantly accumulating gases in the intestines. It is they who can cause the ultrasound of the kidneys with dopplerography to be difficult from the visual side of the issue. To avoid this, you need to follow a few simple preparation tips:
- exclude vegetables and fruits, cabbage in any form, muffins and other bakery products, legumes, juices, soda and milk from the diet a couple of days before the scheduled date;
- on the advice of a doctor, you can take medications from the enterosorbent group, but with an eye on possible chronic diseases like diabetes or hypertension;
- appoint a study of the vessels of the kidneys in the first half of the day to go to the clinic on an empty stomach.
If for some reason it was not possible to schedule an examination in the morning and it was postponed to the afternoon, then a light breakfast is allowed. But in this case, the difference between eating and going to the doctor should be at least 6 hours. It is not recommended to go to the uzist even after a colonoscopy, as there will be a lot of air in the intestine, making it difficult to carefully visualize.
Methodology
Ultrasound of the vessels of the kidneys does not bring discomfort to a person and does not harm health. Modern examination of the vessels of the kidneys with Doppler does not present any particular difficulties. At the appointment, the patient will be asked to undress to the level of the waist, remove jewelry in the area where the direct examination will be carried out. After that, the person will be asked to lie down on the couch for convenience.
In order for the renal arteries to look really good on the monitor, the doctor must ensure close contact between the skin and the sensor of the device. For this, a special gel is used, which does not carry any toxic hazard. Only after that, the diagnostician begins the direct procedure, slowly moving the sensor over the skin.
During the diagnostic process, a person can hear different sounds that come from the speakers of the device. They should not be scared, as this is a normal situation. In this way, the body reacts to changes in blood flow parameters. But if a sharp sound at elevated tones is heard from the speaker of the device, then this may indicate a blockage of the blood passage.
The information received on Doppler ultrasound is entered into an electronic database, and a copy is given to the person who applied for help in his hands so that he can pass it on to the attending physician. Upon request, a person can be given pictures created on thermal paper. They will capture the identified deviations and problem areas, for example, if the size of the vein section does not meet the standards.
In general, dopplerography of the renal arteries takes no more than half an hour. At the end of the event, the gel is wiped off the skin with a regular napkin, and the person can go home, to work, or immediately to an appointment with a specialized specialist to receive an answer on a possible diagnosis. He will not feel discomfort and does not need further observation.
The main goal of dopplerography (duplex scanning) of the renal arteries is to exclude critical stenosis (compression) of the renal arteries. Accurate information about the state of the local vascular network increases the effectiveness of treatment.
Thanks to ultrasound, the doctor will be able to assess the blood flow in the vessels that feed the kidneys - are there any pathologies, and if any, at what stage of development they are.
On the basis of the data obtained, it is possible to discard false diagnoses that could be made without an ultrasound examination, to resolve the issue of the degree of inevitability of surgical treatment and to prescribe the optimal complex of treatment without surgery.
How is a renal artery duplex performed?
The process is as follows:
- an ultrasonic signal comes from the sensor and is directed to the area under study;
- all blood elements are in constant motion, while they are able to reflect the ultrasound signal;
- the reflected signal is processed by a special computer program;
- the output is a color picture with a visual visualization of the blood supply vessel;
- according to the result of the study, the doctor draws conclusions - how well the kidney is supplied with oxygen and nutrients through the blood, whether there are seals in the vascular passages or the threat of their occurrence.
When is an examination ordered?
The majority of patients referred for duplex scanning of the renal arteries are people:
- with persistent hypertension, which is not amenable to antihypertensive drugs. Doctors are especially alarmed by high blood pressure in young people - there are suspicions of a pathology in the area of the renal vasculature;
- who have a predisposition to stenosis, thrombosis, rupture of blood vessels, the development of aneurysms;
- who is about to undergo any kidney surgery;
- suffering from diabetic nephropathy;
- under the control of an oncologist with a suspected lesion in the area of the renal arteries.
Appropriate equipment is currently available in almost all clinics, hospitals and hospitals. Also recently, the branch system of medical advisory centers has been widely developed.
Preparing for duplex scanning
To examine the kidneys and blood supplying arteries, preparatory measures are necessary - to reduce gas formation to the intestines. For this:
- a few days before the procedure, exclude fatty foods, dairy products, confectionery, fruits and vegetables (especially legumes in any form, cabbage) from the diet;
- people with increased flatulence are advised to take espumizan, smecta, enterosgel or activated charcoal the day before the examination (all these substances are adsorbents);
- a few hours to exclude the use of chewing gum, as well as smoking;
- dopleography should be done on an empty stomach (more precisely, eating should occur at least 8-9 hours before the study).
How the examination takes place:
- during the procedure, it is possible to change the patient's posture - lying on the side (lateral access), on the stomach (posterior access), on the back (anterior and posterolateral access), standing (taking into account the individual structure of the urinary system);
- they expose the lower back, where a special gel is applied (it improves the quality of the signal between the skin and the sensor);
- sometimes the patient is asked to take a deep breath and hold his breath (usually this happens in relation to obese patients);
- the whole procedure lasts no more than half an hour;
- no discomfort - immediately after the end of the scan, the patient returns to his usual way of life.
Contraindications and precautions
Duplex examination is completely safe. Even pregnant women and young children can take it. An exception is patients with a pronounced pain syndrome with large diameter aneurysms of the abdominal aorta or its branches.
If at the same time there is a suspicion of possible complications, the issue of dopleography is decided individually:
- most often the procedure is canceled;
- the study can be carried out if the specialist has high-quality ultrasound equipment at his disposal (which reduces the duration of the procedure);
- the study is acceptable if the diagnostician is highly qualified and able to examine the patient quickly, accurately and with a high-quality result.
Special approach in non-standard cases:
- in the retroperitoneal space there may be tumors, abscesses, cysts and other formations - the diagnostician will have to do with posterolateral access (the patient lies on his side);
- the small diameter of the vessel and the large depth of its occurrence complicate the examination process (it will take longer work, the quality of the result is doubtful on low-class equipment).
Research results
It is very important how correctly the ultrasound conclusion is interpreted. What should be revealed as a result of dopleography:
- anatomical location of the arteries;
- places of origin of additional branches;
- the state of blood flow in the vessel;
- elasticity of the vessel wall;
- deviations in the structure of the blood supply;
- condition of the vascular wall for ruptures, aneurysms, thinning, thickening;
- when the arteries are blocked or narrowed, it is revealed whether the cause is an external factor (tumors, abscesses in fatty tissue, hematoma) or internal (atherosclerotic plaques, air embolus, thrombus).
Duplex scanning of the renal arteries is not difficult to pass. And this must be done if there is evidence.
It should be remembered that the quality of the results depends on the experience of the specialist and on the quality of the diagnostic equipment (the higher it is, the more sensitive the sensors and the higher the accuracy of the data obtained).
Doctor Ginzburg L.Z. about preparation: to obtain highly informative data by ultrasound, it is still better to prepare - 3 days of a slag-free diet and use sorbents to reduce intestinal carbonation. Gases significantly reduce visualization on renal ultrasound.
Doppler ultrasound of the renal vessels (USDG) is a diagnostic method that allows you to detect changes in blood flow. It is based on the Doppler effect. The meaning of this effect is the reflection of ultrasonic waves from blood erythrocytes, which helps to visualize the state of the vessels from the inside and evaluate their work. Ultrasound of the renal arteries with Doppler provides an opportunity for specialists to diagnose the state of blood flow in the renal vessels .
This is important because the most important function of the kidneys, the excretory function, directly depends on the state of blood flow.. Doppler ultrasound helps to assess:
- the degree of damage to the vascular walls in atherosclerosis, thrombosis;
- (atherosclerotic plaques, thrombosis);
- blood flow parameters (speed, volume);
- vascular lumen (stenosis, spasms);
- the effectiveness of the prescribed treatment.
Indications for research
Ultrasound of the kidney vessels is prescribed by a nephrologist for many disorders in the kidneys. There are certain symptoms and conditions that indicate the possible presence of kidney disease, which are indications for this ultrasound examination:
- Pain in the lower back.
- Edema of the legs, face.
- Difficulty in urination.
- Increase in blood pressure.
- Changes in the general analysis of urine (OAM): the presence of blood (erythrocytes), protein, an increase in the number of leukocytes, a change in density.
- Attacks of renal colic.
- Late toxicosis during pregnancy.
- Bruises of the lumbar region.
- Acute and chronic kidney disease.
- Systemic diseases (diabetes mellitus, vasculitis).
- In preparation for kidney surgery.
- If a tumor is suspected.
It is worth noting that ultrasound of the kidney vessels has no contraindications and harmful effects on a person.
The only drawback of this method is the difficulty in assessing and examining the small vessels of the kidneys.
Therefore, to clarify the diagnosis, angiography (CT, MRI) is additionally performed. Also, there may be obstacles in the presence of areas of calcification that occur in the vessels with atherosclerosis.
How to Prepare for a Doppler Sonography
In order for the ultrasound to be as informative as possible, it is necessary to responsibly approach the preparation. The most important condition for Doppler ultrasound is the reduction of gas formation in the intestine. This contributes to better visualization of the kidneys.
The following events are being held:
- A few days before the ultrasound, the patient must follow a diet. Foods that contribute to increased gas formation are excluded from the diet: bakery products, cabbage in any form, legumes, raw fruits and vegetables, carbonated drinks, confectionery.
- These days, the doctor prescribes enterosorbents (activated charcoal, espumizan, enterosgel, sorbex) 2 capsules 1-3 times a day as a preparation.
- Ultrasound must be performed on an empty stomach. Do not drink or take medication before the test. If the procedure is scheduled after lunch, then the interval between the last meal and ultrasound should be at least 6 hours. In exceptional cases, the interval may be reduced to 3 hours (severely ill patients).
It is impossible to carry out ultrasound examination of the vessels of the kidneys and their arteries after the following procedures: fibrogastroscopy, colonoscopy. After them, air enters the intestines, which complicates the examination of blood vessels and the diagnosis of internal organs.
Survey methodology
Dopplerography of the kidneys is a gentle and comfortable procedure for the patient. It does not cause discomfort and is painless.
The patient undresses to the waist and takes a sitting or lying position on his side. The doctor applies a contact gel to the area to be examined so that there is no air layer between the sensor and the skin, so there is maximum contact of the sensor with its surface. Then the doctor moves the sensor over the skin in the projection of the location of the kidneys and evaluates the resulting images. The results are recorded on paper and in the photo.
The whole procedure takes no more than 30 minutes.
At the end, the doctor issues a conclusion - a protocol, which contains the following information:
- organ shape (normally bean-shaped);
- outer contour (clear, even);
- capsule structure (hyperechoic, thickness up to 1.5 mm);
- the relative position of the organs (the right kidney is slightly lower than the left);
- comparison of sizes (kidneys of the same size or a difference of no more than 2 cm);
- organ mobility (during breathing up to 2-3 cm);
- anterior-posterior size (no more than 15mm);
- resistance index of the main artery (in the region of the gate about 0.7, in the interlobar arteries from 0.36 to 0.74);
- developmental anomalies and vascular neoplasms are excluded;
- anatomical arrangement of vessels and places of discharge of additional branches;
- the state of the vascular wall (thickening, thinning, aneurysms, ruptures);
- the state of the lumen of the vessel (when narrowing, the reasons are clarified);
- the resistance index is measured in the middle, terminal and proximal sections of the artery (a large difference in the indices in both kidneys indicates a violation of blood flow);
- an assessment is made of the size and structure of the adrenal glands and the structure of the perirenal tissue.
Indicators and norms of arterial trunks and their blood flow
Duplex and triplex imaging of vessels and arteries (photo)
Here are some norms of the vessels of the kidneys when conducting ultrasound dopplerography of the kidneys in conclusion:
Normal artery diameter:
- main trunk - 3.3-5.6 mm;
- segmental arteries - 1.9-2.3 mm;
- interlobar arteries - 1.4-1.6 mm;
- arcuate arteries - 0.9-1.2 mm.
Systolic blood flow velocity in the arteries of the kidney:
- main trunk - 47-99 cm / sec;
- interlobar arteries - 29-35 cm / sec.
Diastolic blood flow velocity of the arteries:
- main trunk - 36-38 cm / sec;
- interlobar arteries - 9-17 cm / sec.
Benefits of Sonography
All the advantages of the ultrasound method listed below help the doctor to quickly make decisions about the necessary methods of treatment. This is especially important when it comes to surgical intervention.
- Non-invasive (no needle or injection).
- Fast results.
- Allows you to identify pathology at the time of examination.
- Allows examination of soft tissues.
- During the procedure, ionizing radiation is not used.
- Availability.
Summing up, we can say that with the help of ultrasound of the vessels, an experienced doctor of ultrasound diagnostics can quickly and easily diagnose most of the pathological conditions of the organ. The study takes a minimum of time, has no contraindications, is absolutely painless and harmless.
Ultrasound of the renal arteries- This is an ultrasound examination, a modern diagnostic method aimed at identifying various pathologies of the kidneys and the genitourinary system. As a result of this procedure, it is possible to assess the condition of the kidney and its vessels. Modern medicine suggests the beginning of the diagnosis of the kidneys with ultrasound. The procedure is completely painless and does not require complex preparation.
Indications for research
Ultrasound of the renal arteries, indications:
Pain in the lumbar region,
- violations in the analysis of urine, - renal colic,
- bruises and injuries of the kidneys,
- systematic increase in pressure,
- transplanted kidney
- inspection for prevention,
- diagnosis of neoplasms,
- Chronic and acute specific and non-specific inflammation of the kidneys.
Preparation for ultrasound of the renal arteries
If you have been assigned Ultrasound of the renal arteries preparation should be an integral part of this procedure.
In the morning, before the procedure, it is not recommended to drink more than 100 ml of water, as well as to use diuretics. If you are overweight or have increased gas formation, then a few days before the ultrasound, it is better to exclude milk, black bread, raw fruits and vegetables from the diet. As you can see, ultrasound does not require complicated preparation, but before the procedure itself, it is better to consult an experienced doctor. It is most convenient to undergo a consultation and examination in a private center, because here the procedure will be carried out by the best specialists in a short time. You don't have to wait long in line to get an ultrasound.
Immediately before the procedure, a special gel is applied to the skin, which provides a better glide of the device over the body, eliminating air between the skin and it. It does not cause allergies and is easily washed off both skin and clothes.
Conducting research
Ultrasound of the renal arteries The procedure is completely painless and harmless. You can perform it both standing and lying down. The kidneys are perfectly visualized on the screen without any special preparation.
The procedure is carried out using a special transducer that sends ultrasonic waves of high frequency. When the device is placed on the abdomen, supersonic waves travel to the tissues and organs, then the waves are reflected from the organs and enter the transducer. The picture is then displayed on the screen.
Most patients undergo ultrasound without any preparation at all. In case of poor visualization, for example, in patients suffering from flatulence or obesity, the study is performed while holding the breath at maximum exhalation.
At Ultrasound of the renal arteries normal- narrowing of the artery up to 5 mm.
After the ultrasound, no special rules need to be observed. You can return to a normal diet, of course, if the doctor does not prescribe a diet for you. An ultrasound of the kidneys will take you only 3-5 minutes with a conventional study and 15-20 minutes with a Doppler one. Results are usually ready within 10-15 minutes after completion of the study.
The structure of the vessels of the kidney
The renal arteries arise from the abdominal aorta just below the superior mesenteric artery, at the level of the second lumbar vertebra. Anterior to the renal artery is the renal vein. At the hilum of the kidney, both vessels are anterior to the pelvis.
The PAP passes behind the inferior vena cava. The LPV passes through the "tweezers" between the aorta and the superior mesenteric artery. Sometimes there is an annular PV, then one branch is located in front, and the other - behind the aorta.
Click on pictures to enlarge.
To study the vessels of the kidney, a convex probe of 2.5-7 MHz is used. The position of the patient is lying on his back, the sensor is placed in the epigastrium. Assess the aorta from the celiac trunk to the bifurcation in B-mode and color flow. Follow the course of the RAA and LAA from the aorta to the hilum of the kidney.
Picture. In the CFM mode, on the longitudinal (1) and transverse (2) sections, the RSA and LSA depart from the aorta. Vessels are sent to the gates of the kidney. Anterior to the renal artery is the renal vein (3).
Picture. The renal veins drain into the inferior vena cava (1, 2). Aortomesenteric "tweezers" can compress the LPV (3).
Picture. At the hilum of the kidney, the main renal artery divides into five segmental ones: posterior, apical, superior, middle, and inferior. Segmental arteries are divided into interlobar arteries, which are located between the pyramids of the kidney. Interlobar arteries continue into arcuate → interlobular → glomerular afferent arterioles → capillary glomeruli. Blood flows from the glomerulus through the efferent arteriole into the interlobular veins. The interlobular veins continue into the arcuate → interlobar → segmental → main renal vein → inferior vena cava.
Picture. Normally, with CDI, the vessels of the kidneys can be traced to the capsule (1, 2, 3). The main renal artery enters through the renal hilum, accessory arteries from the aorta or iliac artery may enter at the poles (2).
Picture. On ultrasound, a healthy kidney shows linear hyperechoic structures with a hypoechoic path in the center along the base of the pyramids (corticomedullary junction). These are arcuate arteries, which are mistakenly regarded as nephrocalcinosis or stones.
Video. Arcuate arteries of the kidney on ultrasound
Doppler of kidney vessels is normal
The diameter of the renal artery in adults is normally 5 to 10 mm. If diameter<4,65 мм, вероятно наличие дополнительной почечной артерии. При диаметре главной почечной артерии <4,15 мм, дополнительная почечная артерия имеется почти всегда.
The renal artery should be assessed at seven points: at the exit from the aorta, in the proximal, middle and distal segments, as well as the apical, middle and inferior segmental arteries. We evaluate peak systolic (PSV) and end-diastolic (EDV) blood flow velocity, resistivity index (RI), acceleration time (AT), acceleration index (PSV/AT). See more.
The normal spectrum of the renal arteries has a pronounced systolic peak with antegrade diastolic flow throughout the cardiac cycle. In adults, PSV is normal on the main renal artery 100±20 cm/sec, EDV is 25-50 cm/sec, in young children PSV is 40-90 cm/sec. In the segmental arteries, PSV drops to 30 cm/sec, in the interlobar arteries to 25 cm/sec, in the arcuate arteries to 15 cm/sec, and in the interlobular arteries to 10 cm/sec. RI at the hilum of the kidney<0,8, RI на внутрипочечных артериях 0,34-0,74. У новорожденного RI на внутрипочечных артериях достигает 0,8-0,85, к 1 месяцу опускается до 0,75-0,79, к 1 году до 0,7, у подростков 0,58-0,6. В норме PI 1,2-1,5; S/D 1,8-3.
Picture. Normal spectrum of renal arteries - high systolic peak, antegrade diastolic flow, low peripheral resistance - RI normal<0,8.
Picture. The spectrum of renal vessels in newborns: renal artery - a pronounced systolic peak and antegrade diastolic flow (1); high resistance on the intrarenal arteries is considered normal for newborns - RI 0.88 (2); renal vein - antegrade flow with a constant rate throughout the entire cardiac cycle, minimal respiratory fluctuations (3).
Doppler for renal artery stenosis
Renal artery stenosis can be found in atherosclerosis or fibromuscular dysplasia. With atherosclerosis, the proximal segment of the renal artery is more likely to suffer, and with fibromuscular dysplasia, the middle and distal segments are more likely to suffer.
Direct signs of renal artery stenosis
The aliasing indicates the location of the turbulent high-velocity flow where measurements should be made. In the zone of stenosis PSV>180 cm/sec. In young people, the aorta and its branches may normally have high PSV (>180 cm/sec), and in patients with heart failure, PSV is low even in the area of stenosis. These features are offset by the renal-aortic RAR ratio (PSV in the area of stenosis/PSV in the abdominal aorta). RAR in renal artery stenosis >3.5.
Indirect signs of renal artery stenosis
Direct criteria are preferred; diagnosis should not be based solely on circumstantial evidence. In the post-stenotic section, the flow fades - tardus-parvus effect. With renal artery stenosis on the intrarenal arteries, PSV is too late (tardus) and too small (parvus) - AT > 70 ms, PSV / AT<300 см/сек². Настораживает значительная разница между двумя почками — RI >0.05 and PI >0.12.
Table. Criteria for renal artery stenosis on ultrasound
Picture. A 60-year-old female patient with refractory arterial hypertension. PSV on the abdominal aorta 59 cm/sec. In the proximal part of the RA with CDI aliasing (1), PSV is significantly increased 366 cm/sec (2), RAR 6.2. In the middle segment of the PPA with color flow aliasing, PSV 193 cm/sec (3), RAR 3.2. On segmental arteries without a significant increase in acceleration time: upper - 47 ms, middle - 93 ms, lower - 33 ms. Conclusion:
Picture. A patient with acute renal failure and refractory arterial hypertension. Ultrasound of the abdominal aorta and renal arteries is difficult due to intestinal gas. On the segmental arteries on the left RI 0.68 (1), on the right RI 0.52 (2), the difference is 0.16. The spectrum of the right segmental artery has the shape of a tardus-parvus - the acceleration time is increased, PSV is low, the apex is rounded. Conclusion: Indirect signs of stenosis of the right renal artery. CT angiography confirmed the diagnosis: at the mouth of the right renal artery, atherosclerotic plaques with calcification, moderate stenosis.
Picture. Patient with arterial hypertension. PSV in the aorta 88.6 cm/sec (1). In the proximal RAP, aliasing, PSV 452 cm/sec, RAR 5.1 (2). PPA aliasing in the middle section, PSV 385 cm/sec, RAR 4.3 (3). In the distal part of the PPA, PSV is 83 cm/sec (4). On the intrarenal vessels of the tardus-parvus, the effect is not determined, on the right RI 0.62 (5), on the left RI 0.71 (6), the difference is 0.09. Conclusion: Stenosis in the proximal section of the right renal artery.
Doppler of the renal veins
The left renal vein runs between the aorta and the superior mesenteric artery. Aortomesenteric "tweezers" can compress the vein, leading to venous renal hypertension. In the standing position, the “tweezers” are compressed, and in the prone position, they open. With Nutcracker syndrome, outflow through the left testicular vein is difficult. This is a risk factor for the development of left-sided varicocele.
Due to compression, the LPV spectrum is similar to the portal vein - the spectrum is higher than the baseline, the constant low speed, the contour is smooth waves. If the ratio of the diameter of the LPV in front of and in the zone of narrowing is more than 5 or the flow rate is less than 10 cm/sec, we make a conclusion about an increase in venous pressure in the left kidney.
Task. On ultrasound, the left renal vein is dilated (13 mm), the area between the aorta and the superior mesenteric artery is narrowed (1 mm). Blood flow in the stenosis zone at high speed (320 cm/sec), reverse of blood flow in the proximal segment. Conclusion: Compression of the left renal vein with aortomesenteric "tweezers" (Nutcracker syndrome).
Compression of the renal vein is possible due to an abnormal location behind the aorta. The diameter ratio and flow rate are evaluated according to the above rules.
The nature of the blood flow in the right renal vein approaches the caval. The shape of the curve changes with holding the breath and can be flatter. The blood flow velocity is 15-30 cm/sec.
Take care of yourself, Your Diagnostician!
Loading...