PRINCIPLES AND MECHANISMS

Principles and mechanisms of picosecond laser treatment of melasma

The pulse duration of picosecond laser is at the picosecond level (10⁻¹² s), which is only one thousandth of the pulse width of traditional Q-switched laser. The principle mechanism is as follows:

The ultra-short pulse width makes it easier for energy to gather and not easy to dissipate outwards, which can break the pigment into smaller particles to a greater extent, and is more conducive to the subsequent metabolism and clearance of the human body.

Different from the photothermal effect of traditional lasers, picosecond lasers mainly rely on photomechanical effects. The photothermal effect is mild, thus reducing the related adverse reactions caused by the photothermal effect in the treatment of melasma with traditional lasers, such as skin burns, pigmentation, etc.

Picosecond laser can also stimulate cell regeneration and promote collagen production. While reducing pigmentation, it can improve skin quality, reduce wrinkles, and achieve a comprehensive skin rejuvenation effect.

Currently, there are three wavelengths of picosecond laser used in clinical practice, namely 532nm, 755nm and 1064nm. Different wavelengths can play a role in different levels and types of pigments when treating melasma.

IMPROVEMENT EFFECT

Picosecond laser improves melasma

A study selected 52 patients with melasma (all female) and used the American Cynosure 755nm honeycomb picosecond laser for treatment. The specific parameters are as follows: wavelength 755nm, frequency 10Hz, spot diameter 6-8mm, energy density 0.40-0.71J/cm², and the patient's skin was slightly red and slightly hot during the treatment process as the treatment endpoint. After the treatment, cold spray for 45 minutes, and let the patient pay attention to moisturizing and sun protection. Picosecond laser treatment was 4 times in total, once every 1.5 months. The efficacy was determined 6 months after treatment. Research data showed that the efficacy of picosecond laser treatment of melasma increased with the number of treatments, and patient satisfaction evaluation also increased with the number of treatments.

Another study explored the effectiveness and safety of 1064nm Nd:YAG picosecond laser in the treatment of melasma. 38 patients with melasma were treated with picosecond laser once a month for 3 consecutive times. The laser parameters were set to ZOOM mode, with a spot size of 7mm, a frequency of 8Hz, and an energy density of 0.75-0.95J/cm². The entire skin was scanned once and the lesion area was scanned twice. The results showed that 1064nm Nd:YAG picosecond laser with large spot, low energy and ZOOM mode is safe and effective in treating melasma, and is worthy of clinical promotion.

According to the "Expert Consensus on Photoelectric Treatment and Repair of Chloasma", picosecond laser can achieve good results in treating melasma and has high safety. Previous studies have reported that the use of large spot and low energy to treat melasma is safe and effective. 1064nm, 755nm, 595nm, 532nm and other wavelengths of picosecond laser can be used for treatment, and the treatment interval is 1 to 4 weeks. There are also reports that the use of 1064nm picosecond laser in fractional mode combined with 4% hydroquinone cream to treat melasma is better than the control side.

However, it should be noted that the cause of melasma is complex and prone to recurrence. When using photoelectric instruments to treat melasma, it is necessary to carefully adjust and set parameters.

References:

1. Expert consensus on photoelectric treatment and repair of melasma

2. Clinical observation of 755nm picosecond laser treatment of melasma

3. Clinical application of picosecond laser treatment of melasma

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, research and development and application of high-end medical beauty optoelectronic equipment based on compliance and product strength, and is committed to becoming a leading enterprise in the field of high-end medical beauty optoelectronic equipment, a provider of integrated diagnosis and treatment intelligent solutions, and a pioneer of medical beauty data integration platform.

Through tackling a series of underlying key technologies, Foremed Legend has now independently developed a number of high-end medical devices such as picosecond laser therapy devices, long pulse laser therapy devices, intense pulsed light therapy devices, photoacoustic imaging skin detection equipment 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 science and technology for good, Foremed Legend will work with industry and ecological partners to bring more safe and effective medical beauty optoelectronic equipment and integrated diagnosis and treatment solutions to the global medical beauty market.