Picosecond Lasers
What are Pico Lasers Treatment?
In the past, Q-Switched lasers were widely practised for removal of tattoos as well as treatment of acquired pigmentation disorders such as melasma, freckles, uneven pigmentation and dull skin.
The Q-Switched laser delivered pulses of high energy in nanosecond domain which is able to selectively target and destroy pigmentations so that your immune cells can eliminate it over time.
Compared to older CO2 lasers and Er:YAG lasers, Q-Switched Nd:YAG and Ruby lasers were relatively selective to pigmentations, and resulted in much lesser adverse affects and recovery time. However, it was soon realised that Q-Switched lasers resulted in a steady state after a certain number of treatments, and further treatments did not improve the condition.
Moreover, prolonged treatment would result in various unwanted side effects were noted such as mottled hypopigmentation as well as postinflammatory hyperpigmentation. The rates of Postinflammatory Hyperpigmentation with Q-Switched lasers has been reported to be as high as 25%.
Picosecond lasers were later introduced, which delivered pulses in the picosecond domain. For reference, a picosecond is a trillionth of a second. Which means 0.000,000,000,001 seconds.
Why deliver laser in picosecond duration?
The shorter the pulse duration, the less bulk heating is generated. But is that necessarily a good thing?
Shorter pulse durations would result in what is called a photo acoustic effect. The rapid heating and expansion of pigments results in a photo acoustic wave which shatters the pigment particles into tiny particles for elimination by your immune cells.
Photoacoustic effect differs from photothermal effect, where longer pulses of energy result in accumulation of heat in the pigment.
A lot of the unwanted adverse affects from laser treatments result from excessive energy causing tissue heating. This in turn could either damage our melanocytes, causing hypo pigmentation (white spots) or overstimulates them, causing hyperpigmentation (dark spots). In worst case scenarios you get a combination of both, resulting in mottled pigmentation.
Therefore, the Picosecond lasers are meant to result in better pigmentation clearance while minimising the adverse affects.
PicoPlus Laser
Picosecond laser is undoubtedly a revolutionary technology, and at the current moment there are only a handful of reliable manufacturers producing solid devices adopting this technology. However, there are still variations in terms of the wavelength, the pulse duration as well as the energy delivery amongst the laser devices. PicoPlus is the latest Picosecond laser by leading aesthetic device manufacturer Lutronics. It was US FDA cleared in 2018, further establishing the safety and efficacy of the device. PicoPlus is also the 1st device approved by the Ministry of Food and Drug Safety (MFDS) for treating melasma. PicoPlus is amongst the few Picosecond lasers that have been certified True Pico by a 3rd party, Korean Testing Laboratory.
How is PicoPlus treatment different from the rest?
PicoPlus offers extremely short pulse duration at 450ps compared to other well known brands of pico laser such as PicoSure and Pico Genesis at 750ps. PicoWay and PicoCare also operates at 450ps, whereas Discovery Pico can operate at 370ps. As mentioned earlier in this article, shorter pulse duration equals better safety. Shorter pulse duration translates to better efficacy because the higher peak power achieved (laser pulse duration inversely related to peak power). Fotona Starwalker PQX with its shortest pulse duration has an extremely high peak power (2.7G) followed by PicoPlus and Discovery Pico both generating the second highest peak power (1.8GW). PicoWay (0.9GW) and PicoCare (1.33GW) have lower peak powers despite also sharing the same 450ps pulse duration. PicoSure has the lowest peak power in this comparison (0.36GW).
Another factor that sets PicoPlus apart is the capability of producing 4 different wavelengths (1064nm, 532nm, 595nm, 660nm) to effectively target almost every type of skin concern, whether it is tattoos and acquired pigmentary disorders, acne and erythema, or even skin rejuvenation for scars and wrinkles. Fotona PQX provides access up to 5 different wavelengths, and PicoCare also has 4 different wavelengths. PicoSure and Pico Genesis has only 2 wavelengths whereas Discovery Pico and PicoWay has only 3 wavelengths. Bear in mind having access to the extra wavelengths are only beneficial in the hands of trained professionals.
This study Choi, M.S., Seo, H.S., Kim, J.G., Choe, S.J., Park, B.C., Kim, M.H. and Hong, S.P., 2018. Effects of picosecond laser on the multi-colored tattoo removal using Hartley guinea pig: A preliminary study. PloS one, 13(9), p.e0203370. showing the effectiveness of different wavelengths in the removal of different coloured tattoos would give us an idea why it is important to have access to multiple wavelengths.
