RU2806873C2 - Method of laser obliteration of superficial convoluted veins - Google Patents

Abstract

FIELD: medicine; vascular surgery.

SUBSTANCE: under constant ultrasound control, the radiation source is introduced by direct traction through a single puncture of the skin by placing a tortuous pathological vessel on an instrument for the entire length of the obliterated vein. An end-mounted quartz light guide with a sharpened end is used as an instrument, during the reverse traction of which a laser effect is applied to the wall of the varicose vein, obliterating it. In a particular case, an end-mounted quartz light guide with a diameter of 950 microns with an end sharpened at 60 degrees is used. In a particular case, the effect on the vein is achieved with the radiation of a solid-state laser resonantly absorbed by water, generating radiation with a wavelength of 1,470 nm and an output power of 6–7 W in a quasi-continuous mode, while the exposure time ranges from 2 to 5 s.

EFFECT: method makes it possible to provide an effective and reliable method of obliterating convoluted tributaries of the saphenous veins due to exposure to the entire length of the pathological vein under ultrasound control with minimal thermal and mechanical effects on the surrounding soft tissue and skin around the treated vein.

1 cl, 3 ex, 4 dwg

Description

The invention relates to medicine, namely to vascular surgery, and can be used in the surgical treatment of patients with varicose veins of the lower extremities.

Varicose veins are a disease that affects the venous system of the lower extremities, with its main manifestations being tortuosity and uneven expansion of the saphenous veins and disruption of the structure of the venous wall. The disease is one of the most common worldwide, affecting up to 70% of the population.

The main method of treating varicose veins is surgical, one of the key points of which is the removal or obliteration of altered saphenous veins with incompetent valve apparatus. Elimination of pathological venous blood flow and venous hypertension in the trunk of the great saphenous vein is a mandatory step in the treatment of varicose veins.

Currently, there are a fairly large number of modern, low-traumatic methods of treating varicose veins [Russian clinical guidelines for the diagnosis and treatment of chronic venous diseases. Phlebology. 2018;12(3): 146-240].

When using non-thermal methods, miniphlebectomy and scleroobliteration are most often used.

The method of miniphlebectomy or microphlebectomy involves the removal of varicose veins through incisions or punctures of the skin using special phlebectomy hooks. The disadvantages of the method include the painfulness of the procedure, damage to nearby lymphatic and blood vessels, nerves, subcutaneous fat and skin, the presence of postoperative hematomas, and possible infection of postoperative wounds.

The scleroobliteration method involves puncture of the vein under ultrasound guidance and the introduction of a phlebosclerosant drug, followed by scarring and obliteration of the vein. Interacting with the vascular endothelium, the drug has a detergent effect on cell wall proteins with a subsequent reaction of the subintimal layers, which causes endothelial death and thrombosis. Under conditions of constant elastic compression, the thrombus is replaced by connective tissue elements and the vein is obliterated. The method is low-traumatic and well tolerated by patients, which allows the intervention to be performed on an outpatient basis without the use of local anesthesia. However, chemical damage to the endothelium does not in all cases result in reliable obliteration of the vein, which leads to both partial and complete recanalization of the sclerosed vein. The method often leads to relapses of the disease, despite strict adherence to the procedure technology, the formation of “coagulum” inside the lumen of the vein, hyperpigmentation with the possibility of skin necrosis.

Thermal obliteration is based on the occlusion (closure) of a vein by exposing the venous wall to laser radiation energy. The laser beam heats the blood in the vessel, producing tiny particles of steam. Coagulation and sealing of the malfunctioning vessel occurs, which further stimulates the process of formation of connective fibers, which over time completely replace the vessel. The laser device functions as a heating device, in which the distal quartz or sapphire tip of the optical fiber acts as a heating element. Typically, the procedure is used for varicose veins up to 1 cm in diameter and is performed for extensive vascular lesions (trunks of the great and small saphenous veins). The main condition for effective laser obliteration (ELVO) of veins is considered to be a relatively smooth course of the vessel. It is very difficult to insert a standard laser light guide, probe or catheter into the tortuous tributaries of superficial veins or varicose veins. In addition, such veins are located close to the skin, which can lead to burns. Therefore, miniphlebectomy or sclerotherapy methods are usually used to eliminate these veins.

There is a known method of endovasal laser obliteration of an incompetent great saphenous vein with postthrombophlebitic changes and the anatomically complex structure of its mouth [RU 2653639, 04/27/2017], characterized by the fact that laser obliteration is carried out in two stages, that is, above and below the impassable section of the vein, following continuously one after another and carried out under constant ultrasound scanning. In this case, lasers with a wavelength of 1550 nm with a constant frequency, with a radiation power of 10 W and a radiation power density of 60-80 J/cm2 are used. Performing endovasal laser obliteration using the claimed method allows one to fully obliterate the required area of the great saphenous vein in parts, even if there is an obstructed section of postthrombophlebitic veins in it.

The disadvantage of the method is the ability to work only with straight sections of the treated vein, which entails multiple punctures, and the impossibility of using the method when treating tortuous veins, or veins of smaller diameter.

There are a number of works in which laser obliteration of veins uses radiation from lasers generating at various wavelengths 532 nm, 810 nm and 980 nm, 1064 nm, and 1470 nm [NavarroL, NavarroN, SalatCB, GomezJF, MinRJ (2002) Endovascular laser device and treatment of varicose veins. US 6,398,777 B1; patent filed in 1999, granted in 2002.

Amzayyb M. et al. Carbonized blood deposited on fibers during 810, 940 and 1470nm; endovenous laser ablation: thickness and absorption by optical coherence tomography. Laser Med Sci 2010; 25: 3:439-447;

Endovenous Laser Treatment of Incompetent Below-Knee Great Saphenous VeinsOriginal Research ArticleJournal of Vascular and Interventional Radiology, Volume 18, Issue 12, December 2007, Pages 1495-1499.].

The disadvantage of the known methods is the fairly high power of the laser radiation used (10-12 W), which can lead to damage to the intima of the vein, tissues and nerves adjacent to the veins.

The closest in technical essence to the claimed invention is the method of obliteration of varicose veins [RU 2212917, 12/13/2001], in which a source of laser radiation is introduced through the wall of the vessel directly into the venous node. Irradiation is carried out from inside the node repeatedly, each time in different directions using a diode laser with a wavelength of 805 nm in a quasi-continuous mode and a radiation power of 2-20 W. In this case, the time of a single exposure ranges from 2 to 20 s. The proposed method allows for complete obliteration of varicose veins exactly at the location of the nodular formation.

The disadvantage of the method is the multiple punctures of the skin and soft tissues required to access each node of the obliterated vessel, which often leads to multiple hematomas and inflammation.

Thus, methods for endovasal laser obliteration of highly tortuous saphenous veins along their entire length are currently unknown.

The technical problem solved by the authors was to expand the range of methods and means of laser obliteration of varicose veins, applicable for the treatment of incompetent, highly tortuous saphenous veins and ensuring safety, efficiency, reliability, low trauma, good cosmetic effect, as well as reducing the overall operation time.

To solve the problem, a method of laser obliteration of highly tortuous veins is proposed, based on the principle conventionally called “Skewer obliteration”.

The technical result consists in the development of a method for laser obliteration of varicose veins, which involves introducing a laser radiation source to the site of exposure, and its subsequent radiation for a time sufficient for complete obliteration, under constant ultrasound control, while with direct traction, the introduction of the radiation source is carried out through a single puncture of the skin and soft tissues by placing a tortuous pathological vessel on an instrument for the entire length of the obliterated vein; in this case, an end-mounted quartz light guide with a sharpened end is used as a tool; with reverse traction, laser action is applied to the wall of the varicose vein, obliterating it. As a tool, an end-mounted quartz light guide with a diameter of 950 microns with an end sharpened at 60 degrees is used.

Optimal results are achieved by exposing the vein to resonantly absorbed water radiation from a solid-state laser, generating radiation with a wavelength of 1470 nm and an output power of 6-7 W in quasi-continuous mode. At

In this case, the time of a single exposure is from 2 to 5 seconds. The proposed method of laser obliteration of highly tortuous veins does not require additional instruments (needles, guides, catheters or introducers, etc.), provides low trauma and a good cosmetic effect, reducing treatment and recovery time patients, as well as reducing the occurrence of hemorrhages and bruises after exposure to laser radiation on varicose veins. The claimed invention is illustrated by the following graphic materials.

Fig. 1 - stages of implementation of the laser obliteration method:

a) vessel and instrument before the operation; 6) positioning of the tool based on the results of direct traction; c, d) stages of reverse traction of the tool,

where 1 is the vessel to be obliterated,

2 - light guide instrument,

3 - vessel closed as a result of foam occlusion

Figure 2 - Figure 4 - examples with the results of applying the claimed method.

The claimed method is carried out as follows.

The area of skin undergoing surgery is treated with an antiseptic solution. Above the clearly tortuous vein 1, a puncture of the skin is performed with an 18 C gauge needle, under the control of ultrasound scanning, a puncture of the distal section of the altered vein is performed with the end of the end light guide 2 sharpened at 60 degrees, then the light guide moves in the direction from the main vein, along the altered vein, along its entire length . The latter is pinned (attached) to the light guide using the principle of a skewer and positioned. The instrument received the code name “Skewer” (translation from English skewer). Then, after insertion of the instrument, a gentle (not tense) tumescent anesthesia is performed by creating a “water” cushion over the vein being treated with a cooled saline solution to divert the vein from the skin. The solution is not injected under the vein, thus the vein is not compressed around the light guide. After that, laser energy with a power of 6-7 Watts is supplied quasi-continuously into the light guide, depending on the diameter of the vein, using a laser device that generates a wavelength of 1470 nm, and reverse traction of the light guide is performed manually under ultrasound control, focusing on the closure of the vein walls . When passing through the venous walls, there is a delay in the movement of the light guide (instrument), associated with the welding of the wall to the light guide, after which the intervenous space between the loops of the tortuous punctured vein is breached, the breakthrough is carried out with the instrument turned off - without laser radiation.

In places where the vessel has an extended or convoluted bend, the tip of the light guide can be rotated in the required direction (Fig. 1c) to organize an additional directed steam jet; irradiation can be carried out from inside each node or bend of the vessel many times in different directions.

The declared laser radiation modes were selected by the applicant experimentally.

Blood is a dispersed aqueous solution of proteins, polysaccharides and other substances, in which 85% is water - a liquid with a high heat capacity, which allows it to very effectively transfer heat to the walls of a pathologically altered vessel (convective). In laser phlebology, end-type optical fibers or fibers with a “radial” attachment are used. The diameter of the quartz core of an end-type optical fiber is usually distributed in the range of 100-600 microns, while the width of the circular strip of the radial nozzle through which the radiation exits is even smaller. Therefore, the intensity of laser radiation, and, consequently, the intensity of the heat flux into which this radiation is converted, will be very high even at low laser radiation powers. When the saturation temperature is reached (100°C at normal atmospheric pressure), the blood begins to boil. Boiling is a phase transition process in which the water contained in the blood turns into steam. The steam forms bubbles, where the dissolved gas also enters. In this sense, we can say that boiling is a process of bubble formation.

During the boiling process, the blood foams and spreads along the vein and, when it stops moving, accumulates, forming foam - foam occlusion of the vessel occurs. Due to the use of an end LED, the boiling of blood in the vein is localized in the vicinity of the end of the optical fiber, where the temperature reaches 100°C, while the temperature of the surrounding liquid does not exceed 37°C (cold environment). At the same time, in a cold environment, steam or vapor-gas bubbles, due to steam condensation, at some point in time stop growing, at which point the reverse process begins - the bubbles begin to collapse. Such locally limited boiling, in which bubbles grow and then quickly collapse, is called “subcooled boiling.” Blood boiling near the end of the light guide forms a directed flow of bubbles. As a result, there is a direct impact of heated and flooded jets moving from the end of the optical fiber, heated to a temperature close to the boiling point, both on the wall of the punctured sections of the vein and on the bends of the venous wall (knee) located around the fiber. When they collide with the venous wall, they spread over its surface (outside the punctured areas of the vein) in the direction opposite to the traction of the light guide. The jets transfer heat at high speed into the intima of the vein, leading to thermal modification (irreversible denaturation of proteins) of the venous wall. As a result, there is a direct impact of the spreading jet of steam both on the wall of the punctured sections of the vein and on the bends of the venous wall (knee) located around the light guide.

After the procedure, the puncture sites are sealed with an aseptic sticker, and compression hosiery of class 2 compression is put on the lower limbs. The tool - Skewer - is an end-mounted quartz light guide with a fiber diameter of 950 microns, with an end sharpened at 60 degrees, a total length of 150 mm, the ratio of the fluorosilicate sheath to the main core is 1.1, the aperture MA is 0.22. External coating SIEL varnish, diameter 1.3 mm. Due to the sharpened end and the rigid working part of the light guide, punctures and placement of a tortuous pathological vessel on the light guide are performed under ultrasonic control; in addition, the possibility of directional positioning of the instrument is provided. This eliminates the additional use of introducers, which significantly reduces the duration of the operation and its cost.

The method makes it possible to provide a reliable, low-traumatic method of obliteration of convoluted tributaries of the saphenous veins, due to exposure to the entire length of the pathological vein under ultrasound control, with minimal thermal effects on the surrounding soft tissue and skin around the treated vein.

This operation is performed on an outpatient basis, does not require general anesthesia, and ensures rapid recovery of the patient after surgery, with a good cosmetic result.

The effectiveness of the method has been proven by more than 100 operations performed by the claimed method at the ambulatory surgery center of the High Medical Technologies Clinic named after. N.I. Pirogov St. Petersburg State University. Examples of clinical use of the method

Example 1. A 46-year-old patient came to the clinic with a diagnosis of varicose veins of the lower extremities without ulcers or inflammation. According to duplex sanitation of the veins of the lower extremities, incompetence of the remaining SPS valve on the right, valve insufficiency of the great saphenous vein and its tributaries on the lower legs, and the superficial accessory saphenous vein on the thigh were revealed (Fig. 2, a - before surgery, b - a month after surgery)

The operation of endovenous laser obliteration of the trunk of the great saphenous vein on the right was performed in a standard way: under tumescent anesthesia Sol. Lidocaini 0.1% - 200 ml., power 8.5 W, constant mode; automatic light guide traction at a speed of 0.5 mm/sec. Dilated tributaries to the legs and the superficial accessory saphenous vein were treated by obliteration according to the proposed method. The diameter of the obliterated vein is 0.8 cm with varixes up to 1.6 cm. The laser power used is 6.2 W, manual traction of the light guide is 0.7 cm per second, exposure of the light guide in the varicose node (or at the bend of the vessel) is 3 sec. An aseptic bandage is applied to the puncture sites, and compression stockings are put on. The patient was discharged from the department on the same day. On examination 1 month after the operation: ultrasonography shows complete obliteration of the trunk of the great saphenous vein and tortuous suprafascial tributaries, there are no signs of recanalization, a good cosmetic effect - no dilated veins, hyperpigmentation.

Example 2. Patient I., 60 years old, came to the clinic with a diagnosis of varicose veins of the lower extremities without ulcers or inflammation. According to duplex sanitation of the veins of the lower extremities, incompetence of the ostial valve of the SPS on both sides was revealed, valve insufficiency of the great saphenous vein in the upper third of the thigh, the anterior vein surrounding the thigh on the thigh and lower leg (Fig. 3, a - before surgery, b - a month after surgery ).

The operation of endovenous laser obliteration of the trunk of the great saphenous vein on the right was performed in a standard way: under tumescent anesthesia Sol. Lidocaini 0.1% - 250 ml., power 8.5 W, constant mode; automatic light guide traction at a speed of 0.5 mm/sec. The anterior surrounding femoral vein was treated by obliteration according to the proposed method. The diameter of the obliterated vein is 1.2 cm with varixes up to 1.5 cm. The laser power used is 6.9 W, the traction of the light guide is manual, about 0.7 cm per second, the exposure of the light guide in the varicose node (or at the bend of the vessel) is 4 seconds. An aseptic bandage is applied to the puncture sites, and compression stockings are put on. The patient was discharged from the department on the same day. After 1 week, the patient underwent surgery on the left lower limb.

On examination 1 month after surgery: ultrasonography shows complete obliteration of the trunk of the great saphenous vein and tortuous suprafascial tributaries, no signs of recanalization, good cosmetic effect - absence of dilated veins, hyperpigmentation.

Example 3. Patient N., 50 years old, came to the clinic with a diagnosis of varicose veins of the lower extremities without ulcers or inflammation. According to duplex sanitation of the veins of the lower extremities, incompetence of the ostial valve of the SPS on the left, valvular insufficiency of the great saphenous vein and its tributaries on the legs were revealed (Fig. 4 a - before surgery, b - one month after surgery).

The operation of endovenous laser obliteration of the trunk of the great saphenous vein on the left was performed in a standard way: under tumescent anesthesia Sol. Lidocaini 0.1% - 270 ml., power 8.5 W, constant mode; automatic light guide traction at a speed of 0.5 mm/sec. Dilated tributaries on the legs are treated by obliteration according to the proposed method. The diameter of the obliterated vein is 0.5 cm with varixes up to 1.3 cm. The laser power used is 6.5 W, the traction of the light guide is manual, about 0.7 cm per second, the exposure of the light guide in the varicose node (or at the bend of the vessel) is 2 sec. An aseptic bandage is applied to the puncture sites, and compression stockings are put on. The patient was discharged from the department on the same day. On examination 1 month after surgery: ultrasonography shows complete obliteration of the trunk of the great saphenous vein and tortuous suprafascial tributaries, no signs of recanalization, good cosmetic effect - absence of dilated veins, hyperpigmentation.

The method makes it possible to provide an effective and reliable method for obliterating convoluted tributaries of the saphenous veins, due to exposure to the entire length of the pathological vein under ultrasound control, with minimal thermal and mechanical effects on the surrounding soft tissue and skin around the treated vein.

This operation is performed on an outpatient basis, does not require general anesthesia, and ensures rapid recovery of the patient after surgery, with a good cosmetic result.

Claims (3)

1. A method for laser obliteration of varicose veins, involving the introduction of a source of laser radiation to the site of influence and its subsequent radiation for a time sufficient for complete obliteration, under constant ultrasound control, characterized in that the introduction of the radiation source is carried out by direct traction through a single puncture of the skin by placing a tortuous pathological vessel on an instrument for the entire length of the obliterated vein, while the instrument used is an end quartz light guide with a sharpened end, with reverse traction the laser is applied to the wall of the varicose vein, obliterating it. 2. The method according to claim 1, characterized in that an end-mounted quartz light guide with a diameter of 950 microns with an end sharpened at 60 degrees is used. 3. The method according to claim 1, characterized in that the effect on the vein is carried out with resonantly absorbed water radiation from a solid-state laser, generating radiation with a wavelength of 1470 nm and an output power of 6-7 W in a quasi-continuous mode, with the exposure time ranging from 2 to 5 With.