Tattoo Removal Devices
Tattoo lasers are one of the most misunderstood and misrepresented devices on the aesthetic market. There are a few companies that sell what they call a "tattoo removal" laser, but some are nothing more than a modified hair removal device and don't work well enough on all tattoo ink colors to satisfy the entire patient base looking for comprehensive tattoo removal services. Most tattoo lasers do not have the energy to completely remove all ink colors in a reasonable number of treatments, and because the patient has to wait between treatments for the skin to heal, this could take a very long time if the system is less effective. With a weak tattoo laser, the possible outcomes would be leaving behind a faded tattoo, requiring patients to spend a lot of money and time to get an acceptable outcome, or pushing the limits of the laser that results in a burn, leaving behind a scar in the shape of the tattoo. Any one of those scenarios will result in a very dissatisfied customer base with a negative public image that makes it difficult or impossible to establish and grow a tattoo removal or aesthetic business.
A tattoo laser is a Q-Switched device. Q-Switched (aka quick switched) basically means it delivers light energy in a very short pulse that is much shorter than a standard laser. Standard aesthetic lasers measure their pulse width in milliseconds (ms) but a Q-Switched laser measures the pulse width in nanoseconds (ns). A millisecond is one-one thousandth of a second. A nanosecond is one-one billionth of a second. The light emitted from a Q-Switched laser acts more like an acoustic wave than traditional light; it still is attracted to a specific pigment or color much like a standard laser is attracted to various chromophores based on the wavelength, but the light blasts the pigment/ink into microscopic particles so it can be absorbed by the body.
The mechanics of the process is that the light is attracted to the ink based on the color of the ink and the wavelength of the laser light. Since the ink resides deep in the skin, the difficulty of the procedure is that you have to deliver the right level of energy to affect the ink without damaging the skin between the surface and the ink. This is done by delivering a very high amount of energy in a very short period of time, hitting the ink with that acoustic blast and generating heat in the tissue only where the ink resides, without creating too much heat in the skin above the ink. To reach deeper in the skin without generating too much heat on the surface, the spot size must be large in relation to the energy applied, since the laser energy creates a profile that resembles a cone; the deeper it reaches into the skin, the more narrow the peak power area becomes until it comes to a point. The area the laser beam can affect shrinks as you go deeper into the skin, reducing the amount of ink the beam will remove. If you reduce the spot size to increase the energy (the power density rule: take the same amount of energy output from a laser at one spot size, reduce the spot size and you increase the light energy of the beam), you reduce the overall area of ink that is treated deep in the skin and this dramatically increases the chance of causing a burn on the surface of the skin. Having a device that can generate a high energy with a large spot size is critical for success with the minimization or elimination of complications.
Here's why the maximum energy of a tattoo laser is critical and the biggest problem with most of the devices currently sold on the market. The lower the maximum energy per pulse the system can produce, the less ink the device will affect per treatment, so a lower powered laser will require more treatments in a series to completely remove a tattoo of any ink color. The base wavelength of a tattoo removal device is traditionally 1064nm (YAG laser) and the laser manufacturer will advertise, or list in the device specifications, the maximum energy at the 1064nm wavelength. Most of the current tattoo lasers are a 1 Joule per pulse system (in the 1064nm wavelength). The 1064nm wavelength will treat black and dark blue inks. A maximum energy of 1 Joule per pulse is sufficient for effective tattoo removal, so a 1 Joule/1064nm device will work well for tattoos with dark ink colors. As you can see, since a large percentage of tattoos are dark in color, even a basic tattoo removal laser can treat a good percentage of tattoo clients. But that is like opening a coffee shop and only selling plain black coffee; you will have many clients, but you will turn a lot of potential customers away or, worse yet, create unhappy clients by trying to serve them something they don’t want. When considering the purchase of a tattoo laser that will be useful for all tattoo types and patients, you have to look beyond the specifications of the base wavelength.
To affect red inks or colors close to that hue, the system is switched to 532nm (when changing a system from 1064nm to 532nm, it is referred to as "doubling" the wavelength), but when you switch to 532nm, you reduce the laser's energy by 55%. So, if you start with a 1 Joule system (1,000mj), when changing to 532nm, you end up with roughly 450mj as the workable energy. 450mj is still a sufficient level of energy, but remember that as you lower the total energy delivered, this means it will take a higher number of treatments in a series to completely remove a tattoo. When setting the system to treat sky blue inks, you install a handset called a dye pack while the system is operated in the 532nm mode. The dye pack contains a dye that alters the light wavelength exiting the handset from 532nm to 585nm. There is also another dye pack to change the wavelength from 532nm to 650nm, to affect the greens. When the 650nm or 585nm dye packs are installed, it further reduces the light energy output by 45% to 65%. This means that, when you start with 1 Joule per pulse in the 1064nm mode, you will end up working with around 200mj or less in the 650nm or 585nm modes. At that low level of output, the spot size must be reduced dramatically to generate enough energy to have any effect on the tattoo, resulting in less ink being removed per session. Treating a tattoo with exotic colors such as turquoise or greens will require many treatments and may never completely remove all the ink, leaving behind a faded image.
A standard treatment involves utilizing the 1064nm wavelength to get the darker colors first (if the majority of the tattoo is made up of dark inks). The patient then must allow the "injury" to heal for 8 weeks or longer between each treatment. If the system has a high enough maximum energy output to safely deliver a large spot, it may be able to remove most if not all of the dark colors in one or two treatments. In the majority of cases, the patient needs to come back for multiple treatments with every wavelength. Next, the system is changed to another wavelength (532nm, 585nm or 650nm) based on the color composition of the tattoo. Most low powered systems do not have enough of an effect on the non-standard colors to remove them in two treatments so again, it will take a number of sessions. Depending on how the treatment/service was sold to the patient, there could be a variety of issues: if sold as a package of a certain number of treatments, the patient will not be happy if they have to pay for additional treatments to remove the remnants of a faded tattoo, and if sold by the practitioner as a complete removal (removal of the tattoo, regardless of the number of treatments) the clinic may lose money.