By Raymond Schoeman
Laser tattoo removal is growing fast, following the popularity of tattooing. Yet, the general perception remains vague and sci-fi like. It even seems a certain perception developed among the younger generations; having a tattoo is no longer the commitment it used to be since it can be ‘zapped’ away at anytime.
Although it is completely possible to remove a tattoo without any scarring or shadows, it takes a much greater commitment than most people realize. I think a great part of this has to do with the mass of YouTube videos showing entry-level equipment creating a spectacular reaction during the first treatment, ‘frosting’.
‘Frosting’ is a shock reaction the body has during a treatment. Since most tattoos are black, you do not need a lot of energy for the first treatment to have a spectacular ‘frosting’. Even though it doesn’t make for good results, it does make good YouTube videos.
You can compare ‘frosting’ in tattoo removal with shedding in hair removal. If you exceed a certain fresh hold energy level, you will have shedding — but not permanent hair removal.
With tattoo removal you have to know how to choose the right wavelength to eliminate the colour you’re working on. Since black absorbs all colours of light, it is the easiest to work on, and have some results on any wavelength you may use. Other colours are not so easy.
The general rule of thumb is that you need to use a wavelength as far away from the wavelength of the colour ink you’re working on. If you work on green ink, which reflects between 495 nm and 570 nm, you will be best served with a laser of 1064 nm.
When you work on red ink which reflects between 620 nm and 800 nm, you rather want to work with a laser of 532 nm. Although 1064 nm is even further away from 800 nm than 532 nm is from 620 nm, you need to keep in mind that red also reflects infrared wavelengths, and will therefore reflect more of the 1064 nm than the 532 nm.
For successful treatment you need as much absorption and as little reflection as possible. But wavelength is not the only parameter that makes for a successful treatment.
For tattoo removal you need to create a photoacoustic reaction. This means that you have to create a shock wave to break the ink particle apart. For this you need a minimum fresh hold energy combined with an extremely short pulse length. Nowadays, you have the choice between nanosecond and picosecond lasers.
For the most effective treatment course, you need a combination of nano- and picoseconds. In the beginning of your treatment course you will need longer nanosecond pulses to break up the larger ink particles. Later on you need to switch to shorter picosecond pulses to refine this process.
You can compare this process to that of a sculptor. He will start with a block of stone that is larger than the figure he wants to create and first has to remove all the excess. For this he uses a heavy-duty chisel. Once the stone is ready to create the figure, he switches over to a finer tool. If he chisels with a fine tool against a big block of stone he will have to work a lot longer because he is only breaking small bits off at a time.
You also have to ensure you have enough energy for a successful tattoo removal treatment. If you under treat, you may still have ‘frosting’ but will have no long-term results. The energy determines the ‘punch’ you will deliver to the ink particle. And if you do not hit hard enough you will not break it apart.
The output energy is one of the greatest factors influencing the price of a machine. For very good reason.
You cannot do tattoo removal with a long pulse laser that causes a photothermal reaction, as you will cause severe damage to the tissue surrounding the ink particle. The concept behind tattoo removal is to create a reaction where you break the ink particle apart without spreading heat to the surrounding tissue.
With a long pulse laser you use the ink particle as an element to create heat that will spread and destroy the surrounding tissue – leading to severe scarring.
