Today, the most widely practised tattoo removal technique by far involves the use of lasers. Concentrated beams of light are targeted onto the skin for fractions of a second, breaking the ink into smaller fragments while leaving the tissue unharmed. This happens because the highly energised light (which must be in the absorption spectrum of the targeted area) causes an explosive effect in the pigment. The high energy heats the ink to a temperature of 900 degrees Celsius for an extremely short time, causing it to explode. The resulting tiny fragments are either pushed into deeper layers of the skin and then absorbed and removed by the lymphatic system, or remain in the skin but due to their smaller size become less visible – at least until the next treatment, when they explode again due to the application of the laser and become even smaller.
For several decades, there have been multiple different types of laser devices, each of which has its unique qualities. Many lasers are used for treatment of skin abnormalities such as spider veins, port wine stains, changes in pigmentation, liver spots and hair removal. Not every laser used in the dermatological field is suitable for tattoo removal. Although the wavelength of older devices (such as argon lasers, ruby lasers and CO2 lasers) allowed a small range of colours to be removed, the overwhelming choice for today’s treatment is a Q-switched YAG laser, of which there are several varieties including Erbium, Alexandrite and Pico.
To create a better understanding of these frequently misused concepts, here is a short explanation. “YAG” is an acronym for a neodymium-doped “Yttrium-Aluminium-Garnet” laser. Neodymium is a chemical element with the symbol Nd and is a rare earth element. A YAG laser is a form of solid state laser which uses a neodymium crystal to produce a wavelength of 1064 nanometres. The wavelength is essential to ensure that the tattoo ink will absorb the light and thus explode. At a wavelength of 1064 nm, black ink is targeted; at 534 nm red ink is the target and 694 nm is the wavelength to target green and blue colours. The term “Q-switch” refers to the ability to shorten the wavelength of the laser through technical means in order to target lower-frequency dyes, causing them to oscillate and ultimately to burst. IPL (Intense Pulsed Light) flash lamp technology, which is predominantly used by non-physicians, does not technically involve a laser but is comparable in terms of its effectiveness and the risks and side effects inherent in its use. It is mainly used for hair removal. (1)