The Versatile Q-Switched ND-Yag Laser (Part I) - Skin Rejuvenation by Laser Toning
The word LASER invokes images of James Bond movies, with a villain using a red-coloured beam that cuts through anything it encounters, including James Bond himself. In reality, LASER, abbreviation for Light Amplification by Stimulated Emission of Radiation, was first built in 1960 and it has a plethora of applications that range from military applications to consumer appliances (such as CD disc optical drives) to medical applications (such as LASIK eye surgery).
You may wonder how something so violent, so strong can be used for something else that are so gentle and precise - the secret is the manipulation of the properties of light to control its focus, penetration of surfaces, its "on" and "off" time to control how much it heats, and the strength to control whether it cuts or burns.
This is usually how I explain to my patients on the concept of LASER in aesthetic treatments, particularly the use of the Q-switched ND-YAG laser that are commonly used in skin rejuvenation, treatment of skin pigmentations and tattoo removal.
LASER also has unique property - it is light that is projected in its purest form, i.e. in a single wavelength of e.g. pure blue, or red light, as compared to IPL that is a projected as a rainbow of lights (Intense Pulsed Light, IPL, is also used in skin rejuvenation, hair removal, etc). This has implications in the depth of skin penetration, and the specific things it could target (pigments, blood, water and tattoo particles).
In the following section, I am going to explain, in simple terms, how the Q-switched laser is used in one of the most common and popular treatment for skin rejuvenation - Laser Toning.
Laser toning is a very popular laser skin rejuvenation procedure performed by aesthetic doctors who may own a Q-switched laser. This procedure is essentially a fuss-free, zero-downtime, inside-out approach of skin rejuvenation. Patients describe that this treatment feel like gentle & warm tapping of the skin surface.
Typically, the laser produced by Q-switched laser reaches to depths of about 100 microns where many important skin cells reside, including that of fibroblasts (collagen producing cells) and melanocytes (pigment producing cells) reside. Through specific settings of the laser, there is delivery of specific amount of heat to specific cells or tissues within the skin, for a specific amount of time.
In laser toning, the controlled heat produced by the laser has 2 effects:
Increase of collagen production by fibroblasts; and
Induction of dermal matrix remodelling by dermal matrix proteins. Cells of our skin that are damaged by UV light are stimulated to repair itself.
In laser toning, the strength of the laser is gentle but strong enough to cause destruction of pigments under our skin. With time, pigments are destroyed gradually without over heating the surrounding skin, hence reducing the risks of burns.
There is also a secondary effect of this treatment - pigment cells are stunned by the laser with regular treatment intervals (2-4 weeks' interval) over several months, thus producing less pigments, and resulting in a fairer complexion.
The beauty of laser toning is that it can be combined with other aesthetic treatments. In my practice, I usually combine laser toning with Intense Pulsed Light (IPL) that penetrates the superficial portion of the skin well and stimulates the natural production of new collagen under the skin to soften the appearance of aging.
Pre-treatment with a gentle chemical peel of the skin also enhances the penetration of both the laser and IPL, thus synergistically enhancing their effects.
Laser toning is also safe enough to be done in conjunction with other non-invasive aesthetic treatments such as neuro-modulating toxins (Botox®), dermal fillers, thread lift, and Micro/Macro-Focused Ultrasound (MMFU) - all of which can reduce obvious signs of aging.
I will explain further the versatility of the Q-switched laser in the next few articles. Suffice to say, aesthetic treatments have changed dramatically with this laser.