Doppler ultrasound (Doppler ultrasound) of vessels of lower extremities
The ability of the ultrasonic beams reflected from the soft tissue of the human body has long been used in diagnostic medicine, including to study the state of cardiovascular system of the lower extremities. In order to assess the nature of blood flow in arteries and leg veins, using Doppler ultrasound of vessels of lower extremities – ultrasound supplemented by Doppler effect. The meaning of Doppler effect is that sound waves reflected from moving blood cells. A special sensor detects the reflected signals processed by the computer and displayed on the monitor screen in the form of color pictures.
What does the Doppler?
The technique has many advantages and helps to conduct a thorough diagnosis of the arteries and veins of the legs:
Allocate common complaint that can push the doctor to the appointment of Doppler:
- Periodic swelling of the foot and lower leg, especially in the evening.
- The color of the skin of the legs became cyanotic.
- Heaviness in the lower extremities (the legs are «buzzing»).
- The leg cramp.
- Pronounced vasodilatation.
- Seal, covered by discolored skin (brown, blue).
- The presence of «stars» and trophic ulcers.
- Feet are constantly cold, quick freeze.
- The feeling of running ants.
- Long non-healing wounds of the feet.
- Pain in the legs while walking, going after the rest.
Do not underestimate the danger of varicose veins — a disease complicated by thromboembolism. Detached thrombus in the worst case may get into the pulmonary artery, which endangers the patient’s life.
Special training to uzdg vessels of the lower extremities is not required!
Principles of conducting research
Before the procedure the doctor may ask about the symptoms, disturbing the patient, to learn the history of the disease. For examination the patient should remove the lower limbs from clothes and lie down on the couch. The study is conducted lying on your back, feet slightly unfolded for examination of the popliteal vein, the patient should lie on his stomach.
Arteries and veins examined by Doppler ultrasound:
- Deep artery of the thigh;
- The lower hollow Vienna;
- Deep vein of the leg;
- Iliac vein;
- The femoral artery and vein;
- Popliteal vein.
On the foot skin is applied a special gel to improve skin contact and conductive ultrasonic beams. The sensor is mounted at different angles for superior image slices of the vessel. The doctor examines the localization of arteries and veins, depth, condition of bifurcations (branching) of blood vessels. Then includes the Doppler and finds the nature of the flow – speed, the uniformity, it is possible to detect various anomalies in the movement of blood through the vessels. Upon detection of a pathology specialist conducts a more thorough diagnosis determine the severity of violations.
Parameters defined during uzdg vessels of the lower extremities:
- ABI (ankle brachial index) – ratio of blood pressure measured at the ankle to pressure on the shoulder. The smaller the value, the worse the blood flow in the vessels of the legs.
- Peak velocity in the femoral artery in normal 100 mm/sec.
- Pulse index tibial artery – the lower the number, the narrower the vessel. Normal is equal to 1.8 m/s and more.
- The turbulent form of flow evidence of incomplete stenosis of the vessel.
- The main blood flow – normal character of the blood flow in the arteries. Changes in this parameter indicate stenosis.
- Collateral type of blood flow is characteristic for places where the blood supply is virtually nonexistent.
At the end of the procedure, the doctor issues a statement in which is recorded all data obtained in the course of the study, and also gives the patient small images on thermal paper, they definitely need to keep together with the conclusion.
The advantages of the method
- Ultrasonic diagnostics of vessels of the legs is a noninvasive technique, the patient is not experiencing any discomfort during the procedure.
- Doppler available to most patients due to relatively low prices.
- No harmful ionizing radiation, therefore, the study can be repeated required number of times.
- Ultrasonic waves can be reflected from the soft tissue, whereby it is possible to obtain a complete picture of the vascular system in the legs. X-rays of such skills are not reflected only from bone structures.
- Doppler displays the status of the arteries and veins in real time, therefore, the biopsy revealed tumors is performed under ultrasound guidance.
Shortcomings of the study
Despite the large number of advantages, Doppler blood vessels of the lower limbs has disadvantages:
- Poor visualization of small arteries and veins with ultrasound.
- Atherosclerotic plaque can impede the flow of sound waves, which greatly complicates diagnosis.
- Ultrasound cannot completely replace angiography, MRI or CT scan. These methods are more accurate.
- As with other examination methods, the information content of Doppler ultrasound depends on the qualifications of the specialist and modern apparatus for the diagnosis.
Summing up, it becomes clear that Doppler ultrasonography of arteries and veins of the legs helps the doctor quickly diagnose the problem, and on the basis of the received data to make a rational treatment regimen of the patient.