Light and heat therapy (LHE-technology): mechanism of action, technique, indications and contraindications

Light-thermal therapy (LHE-technology) - Light (light) and Heat (thermal) Energu (energy), - or light-thermal therapy, implies the use of both light and heat energy of the flash lamp radiation.

The flash lamp has a power of up to 10 J, is filled with a patented mixture of inert gases and has a specific shape of a light pulse for the activation of various chromophores. The heating of tissues and the destruction of chromophores upon irradiation with a light flux of low power with the use of LHE therapy occurs as a result of the application of two effects of the propagation of the light flux:

1. absorption of radiation from the light flux by melanin and other chromophores;
2. light scattering on optically heterogeneous structures of the epidermis and dermis.

The mechanism of action of light-thermal therapy (LHE-technology)

All currently existing technologies, other than LHE, are based on photothermolysis, that is, on the heating of chromophores to a certain critical temperature as a result of light absorption. In this case only the so-called "light" radiation energy is used. However, the target can be heated to the coagulation temperature not only due to the "light" component of the radiation energy, but also due to its "thermal" part, i.e., by exposing the tissues to scattered light, which raises the temperature in the affected zone 4-5 times more than absorbed light. The dissipation effect is used to treat tissues with a heterogeneous organization (degraded collagen and elastin, fibrous tissue, dermal papilla, etc.) for the purpose of heating and destroying chromophores. The use of limited energy makes the procedure safe for surrounding tissues.

The effect on the texture of the skin during light-thermal rejuvenation is achieved by stimulating neo-collagenesis as a result of mild thermal irritation of the dermal collagen. Waves of the visible spectrum act on chromophores in the dermis or at the junction of the dermis and epidermis, while the infrared and close to them rays are directly absorbed by the intra- and intercellular fluid. The resulting slight thermal damage to the papillary and upper third of the reticular dermis leads to the activation of fibroblasts and the synthesis of new collagen and intercellular substance, which continue for several months. This effect, which causes the healing of lesions, leads to an improvement in the texture of the skin, which can persist for several years if the patient uses reliable sun protection. Although the reduction in wrinkles is moderate compared to more aggressive ablative or surgical methods, it is usually appreciated by patients who do not want to spend time on a long recovery period.

Separate indications and techniques

Light-thermal (LHE) rejuvenation pursues certain goals in accordance with the main indications. In the case of pigmentary sun damage, treatment begins at the power recommended for the skin type of the patient, then the power gradually increases, if necessary until redness appears on the pigmented area, but not on the surrounding skin. Then the damage is processed by two passes in each session, the sessions are repeated once a week. The course of procedures is from 3 to 10. To damage the vessels, the power is set in such a way that redness appears scattered throughout the treatment area. Some vessels usually darken, indicating coagulation. For such a case, sessions are usually held twice a week with a course of 7-10 procedures. In the case of lines and wrinkles, the entire aesthetic area is treated with parameters that cause only mild uniform redness, without the appearance of purpura. In each session, two passes are performed with an interval of approximately three minutes, the sessions are repeated approximately once every ten stumps, the therapy continues for 10-15 sessions.

Technique of acne treatment

1. Preparing the skin for acne treatment on the "Spa Touch" device of "Radiancy" company using the "Clear Touch" lamp:

• to treat the skin of the face with the help of milk according to the type of skin;
• tone skin (tonic should not contain alcohol);
• Dry the skin with a napkin.

2. Conducting test flashes - to select the intensity of the flash energy, which is the procedure.

Test flashes are performed on the face at the procedure area, the flash energy is selected in accordance with the customer's skin phototype. The intensity is assessed by the appearance of transient hyperemia at the site of the test flare.

3. The main stage of the procedure.

The whole surface of the face is treated, starting from the forehead area. The manipulator is easily pressed against the skin, the control pedal is depressed, after the readiness indicator is activated, a flash is carried out. The device is ready to work again after 12 seconds.

The processing of all areas is carried out quickly, since in one flash an area of 12 cm ² overlaps . Duration of the procedure is 15-30 minutes.

The pulse duration in the "Clear Touch" lamp is 35 ml. This pulse duration was established experimentally by the developers of the Israeli firm Radiancy in order to:

• effectively effect on the products of vital activity R. Acne - porphyrins (they are the chromophore for the operation of the LHE technique);
• Limit the spread of heat to prevent traumatization of surrounding tissues.

4. Re-treatment of facial skin.

It is carried out necessarily for a more thorough study of problem areas. The client after the procedure may have mild hyperemia on the treated area, which disappears within 20-30 minutes after the procedure.

5. Care after the procedure.

The stage of skin tonification is performed, it is possible to apply a mask. At the end of the procedure, a moisturizing cream with SPF protection is applied.

Procedures for LHE technology lead to good results, after a cycle of 8 procedures, up to 90% of acne is cured.

[1], [2], [3]