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VEIN THERAPY Unsightly facial telangiectasias and spider veins and lower extremities vascular malformations such as hypodermic and endermic veins, red or bluish capillary “barcodes” are a serious aesthetic concern for a large number of patients. Conventional vein treatment methods are confined to electrocoagulation, sclerotherapy and surgery destruction of leg varicosis and small subcutaneous veins. All these methods have substantial adverse effects. E.g., facial veins electrocoagulation implies disruption of the skin surface, is painful, can cause scarring, like shallow craters, and is inapplicable in treatment of leg veins. Sclerotherapy is not recommended for use on the face, and its efficacy is much limited in leg telangiectasias and veins coagulation since it requires the precise pinpoint technique and an exact correlation between vessel and injection needle diameters. Besides, there exist a danger of allergy reactions to a sclerosing agent and trophic skin disturbances. Surgery method is commonly used for varicose veins treatment in clinical cases. The above mentioned techniques do not completely comply with modern aesthetic medicine standards, namely:
Since recent phototherapy technologies were introduced to the aesthetic medicine new methods of unsightly vein treatment have been developed on the principle of selective thermolysis: light is selectively absorbed by the blood in the target vessel and converted into heat energy, thus raising the blood temperature to higher than the point of coagulation. This induces local blockage of the target vessel with minimal effect on the surrounding tissue. Selective thermolysis requirements for treatment of various vascular lesions presuppose: 1. An appropriate selection of spectrum range providing sufficient light penetration into the skin (up to 4 mm) and selective coagulation of target vessels with minimal skin heating. Figure 1 shows the penetration depths of light in skin and blood depending on wavelength [1]. Light acceptors are melanin – the pigment found in skin, and blood haemoglobin; their competition determines selectivity of light absorption and consequently a level of treatment efficiency.
Fig.1 As it is seen from the figure, in the range of 500-900 nm wavelength high melanin absorption limits light penetration into the skin. Therefore, light sources intensively operating in this spectrum range suit for coagulation of shallow superficial vessels only. This refers to pulsed lamp light sources (500-1100 nm), the 2nd harmonic of an Nd: YAG laser (532 nm), dye laser systems (515-600 nm), and an Alexandrite laser (755 nm). Besides, high melanin absorption capacity in the short wavelength range together with high fluences needed for effective coagulation limit use of the above devices for I-II skin phototypes because of probable complications such as permanent pigmentary changes from hyper- to hypopigmentation.
Fig.2 The analysis proves that only long wavelengths of 1000-1100 nm, providing the same blood absorption as “shorter” wavelengths, can ensure 4-4,5 mm penetration depth required for coagulation of large and deep vessels, as well as this spectrum exceptionally suits for treatment of I to V skin type patients. 2. Providing fluence sufficient for coagulation of various sized vessels in the whole vessel cross section. The deeper is vascular lesion depth the higher fluence is required to thermally “seal” the vessel. Increasing fluence in the short-wavelength spectrum raises a danger of burns and pigmentary changes due to high melanin absorption in the epidermis. Since melanin absorption is very low at long wavelengths the applied fluence can be as high as 200-250 J/cm2 without any danger for the skin what allows for treatment of the largest and deepest vessels. 3. Adjustability of pulse duration for optimization of control over the treatment procedure of various sized vessels. A possibility to vary the pulse duration in a broad range is very topical as it allows in combination with an appropriate fluence to customize parameters for each treatment case, and thus to efficiently target veins of various diameters, colour, depth, and with different thermal relaxation time. Theoretically the laser pulse duration should be lower or equal to the thermal relaxation time of a target blood vessel, but higher than that of the surrounding epidermis. Under the influence of such pulse duration the treated vascular area accumulates heat energy, while microvasculature and epidermis partially scatter the heat; so the selectivity of treatment in respect of microvasculature improves and the epidermis is prevented from damage. The above analysis evidences that the optimum choice for efficient treatment of vascular lesions is a light source with the 1000-1100 nm wavelength providing fluence of 200 – 250 J/cm2 and pulse duration of 10-50 msec. A demand for reliable and affordable systems, friendly in use for both a patient and a physician and meeting the above requirements encouraged the development and wide spread at the cosmetic surgery market of Nd: YAG lasers (1064 nm) with a “long” pulse (up to 50 msec). The 1064 nm wavelength is well absorbed by haemoglobin and deeply penetrates the skin. Minimal melanin absorption allows using such systems for treatment of patients of all phototypes. An extended research undertaken by practicing cosmetologists has proved the high efficacy of the Nd: YAG laser in targeting vascular malformations of various types [1, 2, 4, 5]. Excessive leg veins are the main concern for the majority of patients with vascular lesions [2]. Short wavelengths can be used exceptionally for treatment of the superficial telangiectasias on the legs, but cannot eradicate deeper reticular veins. The latter are the cause of leg telangiectasia in 90% of treatment cases, as ultrasound studies prove [3]. That is the reason why most patients are interested in removal of vein combinations with different size and depth. Due to wide opportunities of adjustable laser parameters – fluence, pulse duration and pulse repetition rate – Nd: YAG lasers are the “golden mean” for efficient treatment of superficial and deeper vessels. Applying Nd: YAG lasers for targeting large (up to 4 mm) leg veins requires higher fluences (200-250 J/cm2) and “longer” pulses – up to 50 msec. Smaller facial veins are better treated with the 10-15 msec pulse duration at fluence of 80-150 J/cm2. Side effects are transient redness, moderate hyperemia and mild edema when the treatment is performed over the whole face. These effects are not observed at treatment of local vascular lesions (spider hemangioma or separate teleangiectasis). This means that the patient returns to active life-style immediately after the procedure and changes in his/her looks are not that obvious. After the treatment of leg vascular lesions a transient edema of the target site and further mild hyperpigmentation where large vessels were removed can be observed, those effects resolving within several weeks. As materials of the 22nd Annual Meeting of the American Society for Laser Medicine and Surgery, April 10-14, 2002 [5] state, at the present day only Nd: YAG lasers with “long” pulses compete with the two traditional vein treatment techniques – sclerotherapy for superficial telangiectasias and reticular veins and surgery for deep varicose veins, avoiding adverse effects of both these methods. The DeLight laser system with 1064 nm wavelength, 5 mm beam diameter, fluence of up to 300 J/cm2 and variable pulse duration from 10 to 50 msec has been developed by SOLAR LS with the account of all practical experience acquired in laser dermatology in the recent years. In combination with the efficient cooling system DeLight provides precise energy delivery and adjustable pulse duration for successful and painless removal of unsightly vascular lesions not only at the “classic” site – face – but also on legs thus extending a potential number of patients who would prefer to replace time-consuming and painful sclerotherapy procedures with the fast, safe and effective laser therapy enabling successful treatment of any skin type at any time during the year.
1. Effective Treatment of Deep and Large Vessels with VascuLight.
PhotoDerm. Application Notes. 1998; 1; 6.
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