DISCREPANT WITH

The mechanism of action is inconsistent with the target

The target of laser treatment for skin vascular diseases is blood vessels and vascular endothelial cells, and the target chromophore is oxygenated hemoglobin. The pulse width of picosecond laser is much smaller than the thermal relaxation time of melanosomes, and it mainly acts on pigment targets such as melanosomes. It has a significant effect in treating pigment-proliferating diseases, but is not very targeted for vascular diseases such as telangiectasia.

The absorption peak of oxygenated hemoglobin is in the range of 418nm (blue), 542nm (green), and 577nm (yellow). 577nm wavelength laser is considered to be an ideal light source for treating vascular diseases. Picosecond lasers mainly include three working wavelengths: 755nm, 532nm and 1064nm. Although the 1064nm wavelength can be absorbed by the peak of hemoglobin, the short pulse width and extremely high peak power of picosecond lasers can easily rupture blood vessels and cause adverse reactions such as purpura.

RECOMMENDATION

Lack of indications

In the 2022 version of the expert consensus on the clinical application of picosecond lasers, there is no indication for telangiectasia. In clinic, pulsed dye laser (PDL) and intense pulsed light (IPL) are recommended as the first choice for the treatment of telangiectasia.

PDL treatment of telangiectasia and priority

ADVANTAGE

Principle of action and advantages

PDL is a liquid laser with an organic fluorescent dye as the medium. Its wavelength is close to the absorption peak of oxyhemoglobin, 577nm. It is the gold standard for the treatment of facial vascular diseases. It can convert light energy into heat energy through selective photothermal effect, causing microvascular damage and coagulative necrosis at the lesion site. At the same time, sufficient thermal damage further leads to coagulation of the vascular wall and occlusion and regression of the blood vessels, thereby achieving the purpose of treatment.

Common PDL equipment includes Cynergy and Vbeam. Cynergy has a wavelength of 595nm, a pulse width of 2-20ms, and an energy density of 8-15J/cm²; a wavelength of 585nm, a pulse width of 0.5-40ms, and an energy density of 5-7J/cm².

Vbeam has a wavelength of 595nm, a pulse width of 1.5-10ms, a spot diameter of 7mm, and an energy density of 8-14J/cm². During treatment, the pulse width should be determined according to the size of the blood vessels. Extending the pulse width to 6-10ms can reduce the peak power, reduce the occurrence of purpura, and reach a sub-purpuric dose, so that the immediate reaction is the disappearance of superficial small blood vessels or the darkening of the color of thicker blood vessels.

The interval between PDL treatments for telangiectasia is generally 4 weeks. After multiple treatments, the lesions can be improved or even cleared. It is mainly suitable for small-scale, patchy lesions in the early stage of hyperplasia, which helps to prevent the lesions from further expanding and improve function and appearance.

PDL treatment causes obvious pain, but although the use of surface anesthesia can relieve pain, it may cause vasoconstriction in the treatment area, affecting the efficacy, and pain is also a sign of possible adverse reactions, so anesthesia should be avoided before treatment. Its adverse reactions mainly include transient edema and erythema, and purpura is a common adverse reaction, but the occurrence of purpura reactions can be effectively avoided by applying PDL with long pulse width and subpurpuric dose.

IPL treatment of telangiectasia and preferred choice

IPL treatment is based on the principle of selective photothermal action. Its wavelength is 400-1200nm, and it is continuous, polychromatic, non-parallel, and incoherent. It can transmit multiple wavelengths of light with different intensities at the same time. By selecting different filters, light of different wavelengths is emitted to target specific pigment groups. Oxygenated hemoglobin has a strong absorption of wavelengths of 400-600nm. IPL in the appropriate wavelength band can safely and effectively treat vascular lesions and achieve the purpose of treating facial telangiectasia. At the same time, IPL can also use the photothermal effect to stimulate the contraction, rearrangement and regeneration of skin collagen, improve the overall skin texture, and be used for skin rejuvenation and treatment of photoaging.

ADVANTAGE

Treatment parameters and applicability

For blood vessels of different sizes, the treatment parameters are different. Smaller blood vessels should choose lower energy, shorter pulse width and larger spot size; larger blood vessels require higher energy, longer pulse width and smaller spot size.

Compared with PDL, IPL has the advantages of large spot, fast recovery cycle and good tolerance, and can be used as a substitute or supplement for the existing laser equipment to treat telangiectasia.

References

1.2022 version of the expert consensus on the clinical application of picosecond laser;

2. Progress in photoelectric treatment of facial telangiectasia Zhao Li Sun Li Chin J Laser Med Surg, April 2023, Vol 32, No. 2.

The core founding team of Suzhou Foremed Legend Medical Technology Co., Ltd. comes from Peking University and other well-known universities at home and abroad. Foremed Legend focuses on the design, development and application of high-end medical aesthetic optoelectronic equipment based on compliance and product strength, and is committed to becoming a leading company in the field of high-end medical aesthetic optoelectronic equipment, a provider of integrated diagnosis and treatment intelligent solutions, and a pioneer of medical aesthetic data integration platform.

Through tackling a series of underlying key technologies, Foremed Legend has now independently developed a number of high-end medical equipment such as picosecond laser therapy devices, long pulse laser therapy devices, intense pulsed light therapy devices, photoacoustic imaging skin detection devices and cold air therapy devices, and continues to deepen the research and development of core product technologies, using better technical solutions to benefit the vast number of beauty seekers.

Adhering to the principle of technology for good, Foremed Legend will work with industry and ecological partners to bring more safe and effective medical aesthetic optoelectronic equipment and integrated diagnosis and treatment solutions to the global medical aesthetic market.