From this article you will find out: what is the purpose of rheovasography, what is it, when it is suspected of which diseases it is shown. Rules of carrying out and principles of decoding of results of research will be considered.
Contents of the article:
- How the
- is being tested Indications
- Contraindications
- Obtaining results
- Additional tests
Rheovasography( abbreviated RVG) is a diagnostic method that allows to assess the functional state of blood flow in the vessels of the extremities. Reovasography helps to detect areas of complete, partial closure of the lumen of arteries and veins due to inflammatory disease or atherosclerosis. It also makes it possible to judge whether there is or not a vascular insufficiency( that is, whether the vessels cope with their function).
The data is obtained by recording the electrical resistance when subjected to high-frequency current on the area of the body being examined. Interpretation of the results is based on the analysis of the filling of blood vessels during the contraction of the ventricles of the heart( systole), the study of patency and contractility of the vessels of the extremities.
Rheovasography procedure The study is conducted by a physician of functional diagnostics.
Do not confuse rheovasography with rheoencephalography. In the second case, it is a question of studying the blood flow of the vessels of the head.
How does the study
Reovasography is a painless procedure and in part resembles the removal of an electrocardiogram. The patient needs a little preliminary preparation for the study. It includes:
- Termination of any physical activity at least 15 minutes before rheovasography.
- Quit smoking at least 2 hours before the procedure. Nicotine, contained in tobacco, causes vasoconstriction and, therefore, can cause distortion of results.
- Discontinuation of medication the day before the study. This is due to the fact that some of them are able to influence the condition of the vascular wall, the fluidity of the blood. If the drug cancellation is not possible( for example, with antitumor therapy), the doctor should be warned about this.
RVG is performed in the supine position, for which a couch is provided. Examined limbs( legs and arms) should be exposed. After the patient occupies a comfortable position, his skin in the area of the sensors is degreased with alcohol.
Depending on the blood flow of which limbs will be analyzed, the region of the location of the recording electrodes differs. When assessing the functional activity of blood vessels, the sensors are superimposed on the fingers, hands, forearms, and shoulders. If reovasography of the lower extremities is performed, the electrodes are placed on the feet, legs and thighs. There are no other differences between the studies of limbs.
After the electrodes are installed, the indicators are recorded. Results in the form of a curve are displayed
Results of rheovasography Indications
The study is designed to diagnose diseases and the vascular bed and their complications.
Complaints serving as the basis for the procedure
- Feeling numbness and cooling in the extremities,
- cramps of legs and hands,
- sudden change in the coloration of the skin of the extremities.
Diseases suspected of being reovasographed
- Atherosclerotic lesions of the vessels of the extremities( deposition of plaques narrowing the lumen of the arteries);
- varicose veins( pathology, accompanied by a violation of outflow of blood in the deep and superficial veins of the lower extremities);
- thrombophlebitis( inflammation of the venous wall with the formation of a thrombus on it);
- Raynaud's syndrome( a condition that manifests itself in the form of excessive spasm of the arteries of the fingers);
- obliterating endarteritis( inflammatory disease of the internal wall of arteries, eventually leading to complete blockage of blood flow at the site of injury);
- vascular complications in diabetes mellitus;
- peripheral vegetative insufficiency( disturbance of vascular channel functioning due to disturbance of its nervous regulation).
Varicose legs is an indication for carrying out rheovasography. As a rule, the doctor prescribes the RVG of the lower extremities immediately after the appearance in the patient of such signs as loss of sensitivity, edema, and changes in the color of the skin. Contraindications
RVG is a research technique that does not have absolute contraindications. Electrodes are not superimposed on the area of wounds, trophic ulcers: to perform the procedure, choose an unaffected place above or below the damaged area.
Obtaining the results of
The duration of the study is not 15-20 minutes. The waiting time for the results of rheovasography does not exceed half an hour. The cost of the procedure depends on the clinic, which is held, and is in the range of 500-2500 rubles.
When decoding, the expert analyzes the symmetry of the oscillations, the height of the descent and lifting of the fixed lines. The obtained results are written in the form of indices.
Rheogram Key indicators:
- Rheographic index. He talks about the general filling of the arterial bed of the extremities studied. The unit of account is om. The results are from 0.05 Ohm and higher. Light arterial insufficiency fluctuates within 0,04-0,05 Ohm. The indicator below 0.04 Ohm allows to assume the presence of the expressed infringement of a blood flow.
- Elasticity index. Characterizes the level of vascular tone. Normal indicators start at 0.4.The index within 0.2-0.4 indicates a moderate hypotension. Anything below 0.02 is a sign of a sharp decrease in the tone of the vascular wall.
- Index of outflow. Helps to judge the intensity and rate of outflow of blood in a venous bed. The normal RVG index is the index in the range of 0.2-0.5.Numbers exceeding this threshold indicate a violation of venous outflow and a high risk of formation of thrombi.
- Index of peripheral resistance. Describes the degree of resistance of the vascular bed in the study area. In the absence of pathology, it ranges between 0.2-0.45.A sharp deviation in a large( more than 0.55) or less( below 0.15) side indicates a violation of vascular blood flow.
Additional tests
Altered indices recorded with rheovasography do not necessarily indicate damage to the vessel walls. Signs of blood flow disorders can be caused by spasm, which is episodic( functional): this result can be obtained if the rules of preliminary preparation are not complied with. To determine what it really is - vascular damage or temporary spasm - the study is conducted with two additional samples: nitroglycerin and compression.
- In the sample with the drug, rheovasography parameters are taken twice. Initially, the study is performed before taking nitroglycerin, then - after resorption of the tablet. The doctor compares the two RVG results with each other. If the indicators do not have significant differences, we can talk about damage to the vascular wall. In the case when these studies significantly improved after taking nitroglycerin, a functional spasm is assumed.
- Compression test is based on compression of the extremity by a cuff. The study, like the previous one, is carried out twice. The results of the rheovasogram are compared before and after cuff application. The sample helps to assess the rate of recovery of vascular outflow during compression of deep veins.
