Duplex Vessel Scan - Causes, Symptoms and Treatment. MF.

Indications
Contraindications
Preparation and implementation of
Decoding results
Complications

Currently, the medicine offers a fairly wide range of instrumental diagnostic methods that allow to confirm or deny the presence of a specific diagnosis with a high accuracy in a patient. One of them is a duplex vascular scanning - a method of examining blood vessels based on the application of the Doppler effect with the help of ultrasound.

Ultrasound is not absorbed by the soft tissues of the body( muscles, vascular wall, internal organs), but is reflected from them and is displayed on the monitor of the device as a two-dimensional image by digital devices. In the case of studying structures with moving fluid media( vessels in this case), ultrasound not only reflects from moving blood elements, but also changes its frequency depending on the speed of movement of the elements, which is recorded on the computer screen and gives an idea of ​​the blood flow velocity. This is called the Doppler effect.

Thus, duplex vascular scanning is an instrumental method for diagnosing diseases of the arteries and veins that allows you to visualize virtually any blood vessel in the human body in real time, assess the degree of disturbance of blood flow in it, and reveal the presence of changes in the blood supply of surrounding tissues.

This image of the vessel is seen by the doctor on the

monitor. The advantages of the method include non-invasiveness( absence of implantation in the body tissues), absence of radiation load, availability( in modern medical institutions, good equipment with the necessary equipment), the ability to accurately diagnose the existing vascular pathology.

Indications for duplex vessel scanning

This method is assigned when the doctor suspects the presence of the following pathological conditions:
- abnormalities or deformations of the vessels that interfere with normal blood supply of organs,
- atherosclerosis of the aorta and its branches,
- obliterating atherosclerosis of the vessels of the lower extremities,
- thrombosis of veins and arteries,
- varicose veins of the lower extremities,
- endarteritis and vasculitis( inflammation of the vascular wall),
- diabetes mellitus and his donkey(
- arterial hypertension( in combination with impaired brain function - dyscirculatory encephalopathy),
- aortic aneurysm,
- heart defects( eg, aortic insufficiencyvalve, leading to a violation of blood flow in the vessels supplying the brain),
- the pathology of cerebral vessels in newborns.

During the examination, it is possible to diagnose diseases of the following groups of vessels:

1. Blood flow assessment in brachiocephalic( brachiocephalic) arteries - general, external and internal carotid arteries are visualized.
Examination is necessary if the patient complains of a certain nature:
- frequent headaches, migraine,
- falling with or without loss of consciousness,
- "noise" in the ears, flickering before the eyes,
- transient ischemic attacks
- frequent dizziness
2. Estimated blood flow of transcranial( intracranial) vessels - anterior, middle and posterior cerebral arteries:
- is performed in combination with scans of brachiocephalic arteries.
3. Diagnosis of arteries and veins of the extremities is necessary in case of symptoms such as:
- the presence of vascular "stars" on the legs,
- varicose veins of the lower extremities,
- pronounced edema of the lower extremities, worse when walking,
-pain, fatigue in the hands or feet,
- chilliness of the limbs,
- intermittent claudication syndrome - for example, in people smoking a large number of cigarettes over a long period of time, a persistent vascularspasm, leading to a violation of the blood supply to the muscles of the legs and feet,
- a change in skin color( blue, violet color) in combination with significant pain can be indicative of acute venous or arterial thrombosis.
4. Diagnosis of diseases of the aorta and its branches :
- an aneurysm of the ascending, thoracic, abdominal aorta.
5. Diagnosis of kidney, liver, thyroid gland, prostate, eyeball diseases :
- tumors of relevant organs for evaluation of vascularization degree in them,
- cirrhosis of the portal vein thrombosis with assessment of intrahepatic blood flow,
- chronic renal failure, glomerulonephritis,
- diabetes mellitus with damage to the vessels of the fundus, leading to blindness, eyeball injuries, etc.

Contraindications for researchNia

Just as for a standard ultrasound, duplex scanning of arteries and veins absolute contraindications exist. It is quite possible technical difficulties, when ultrasound can not "get" to the vessel under study, for example, with a high degree of obesity in the patient in the study of blood vessels of the liver and kidneys, traumas, open fractures of the skull, orbit, limbs, the presence of extensive wound surfaces on the skin in the projectioninvestigated vessels.

Preparation for the patient for duplex scanning of arteries

No special preparation is necessary. The patient can observe the usual daily routine and take the usual amount of food and water.

How is the research done?

For the duplex scanning of arteries, it is necessary to have an ultrasound scanner with software( equipment capable of perceiving reflected ultrasonic beams, register them as graphic curves and convert to a two-dimensional image with color mapping of blood flow) and an ultrasonic sensor.

The patient can be taken to the ultrasound diagnosis room in a planned or emergency order. In a planned order, he is sent from a clinic or profile department of the hospital where he is currently in hospital, and for emergency indications, a person with suspected acute thrombosis, ischemic stroke, exfoliates the aortic aneurysm and other acute vascular diseases.

After the patient is taken to the office, he is laid on the couch and is asked to release the part of the body being examined. Further, the doctor applies a gel - conductor to the skin for better "adhesion" to the sensor skin and better patency of the ultrasound beam and proceeds to the study. In the process, access is made for ultrasound at different points in the projection of the vessel under study.

For example, when scanning carotid arteries and cerebral arteries, access is through the skin and neck muscles, as well as in the area of ​​the connection of the skull with the vertebral column( craniovertebral articulation), above the temporal bone, over the occipital mound, in the orbit. When scanning the aorta and its branches, renal and hepatic vessels, the doctor applies a gel and works on the skin of the chest and abdomen, while examining the vessels of the limbs - on the skin of the hands and feet, corresponding to the course of the main vessels. At the last examination, the patient may be asked to stand up for scanning in the standing position( this is important for evaluating the perforating veins passing through the deep and superficial veins of the shins), and also perform a Valsalva( straining) test to determine the change in blood flow in the veins at the time of sampling.

At this time, all information received by the scanner is processed by digital devices and displayed on the computer monitor of the doctor in the form of a color image and quantitative characteristics of the blood flow in the vessel, which the doctor evaluates and interprets the results.

The time of the examination is 20 - 30 minutes, after which the doctor issues his opinion to the patient for subsequent presentation to his treating doctor. In the case of a planned examination, the patient goes home, and when examined for emergency indications, he is hospitalized in the specialized department for further observation and treatment.

Decoding of parameters of duplex scanning of vessels

Not every patient will be able to understand written in conclusion after the scanning. In principle, to try to understand this and do not need, because this information is purely medical in nature and is intended for professionals competent in this field. But still, every person has the right to know about the results of various diagnostic methods, so we will dwell on the main indicators of duplex scanning of the arteries and veins and try to figure out what can be indicative of the normal state of the vessels, and what about the pathology.

So, in conclusion, the patient can see the following characteristics( may vary depending on the group of vessels being examined):

1. Quantitative characteristics of the Doppler spectrum:
- peak systolic blood flow velocity
- terminal diastolic blood flow velocity
- time-average maximum blood flow velocity
- time-average velocity of blood flow
- resistance index
- pulsator index

Practical value of these indicators has systolic velocity,since it is he who speaks about the presence of stenosis( narrowing) of the vessel, for example, as a result of an atherosclerotic lesion of the vascular wall. The second - the fourth indicators are used mainly for formulas that calculate the last two, also having practical value - for example, the higher the resistance index, the greater the resistance of the vascular wall to the blood flow, as it loses its elasticity, which occurs in hypertension, diabetic angiopathy, parietalthrombi, atherosclerotic plaques. Normally, some vessels, such as the brachiocephalic trunk and subclavian arteries, are highly resistant.

2. Qualitative characteristics:
- straightness of the artery or presence of deformations, tortuosity, aneurysms( protrusions) or other anomalies
- measurement of the artery diameter( cross-sectional plane is used)
- measurement of the intima-media complex( internal endothelial lining of the artery and middlemusculoskeletal membrane)
These indicators show the degree of narrowing in arterial hypertension, the presence of mural overlays( thrombi, atherosclerotic plaques).In case of a clot of a plaque, their location, size, echogenicity( elevated, medium, low), structure, surface( smooth, uneven, with ulceration for plaques) are described.
- for veins, the presence or absence of enlargement, varicose transformation, failure of the valves of the veins( which contributes to stagnation in them and varicose dilatation) is indicated for the veins in the conclusion, whether the vein is compressed during compression( pressure of the sensor determines the elasticity of the vein wall), the determination of the retrograde( inverse)blood flow during the Valsalva trial( normal sample should be negative).

Obtained characteristics must be analyzed by the attending physician-therapist, cardiologist, neurologist, vascular surgeon, in order to determine the further tactics of patient management and the choice of the optimal method of treatment.

Complications of duplex scanning of vessels

There are no complications during the survey, therefore this method can rightly be called one of the safest diagnostic methods.

Doctor therapist Sazykina O.Yu.