How Laser Tattoo Removal Works
Tattoos and tattoo removal have existed for ages. Since the time that tattoos were first used as a form of punishment or branding, people have sought ways to remove them. Fortunately these days, the decision to remove a tattoo is usually personal and related to one’s changing tastes and outlook on life.
Before lasers, tattoos were able to be removed in a number of ways, including salt-abrasion (salabrasion), dermabrasion, acid removal, or frank surgical excision. These methods were quite effective, but were painful and left scars. Laser tattoo removal originally started as a way to burn off a tattoo. Lasers such as the CO2 and argon lasers were used but were not much better than destructive surgical methods, leaving behind open wounds that had to heal over time. The arrival of Q-switched lasers was a watershed moment in laser tattoo removal. These lasers work by a completely different mechanism than ablative lasers (the kind that destroy the skin). A q-switch is a super-fast shutter that allows the emission of a very short burst of laser light, in the nanosecond range. The light is also sent out at a very high energy, all packed into that short burst. The effect on the tattoo ink is similar to throwing an ice cube in a glass of warm water – it fractures. The heat of the laser is absorbed preferentially by the tattoo pigment, but it occurs faster than the ink particle can thermally expand, causing it to fracture into tiny pieces. These smaller pieces become small enough to be digestible by the immune white cells of the body and are taken away to distant areas. As this course of action is repeated, the tattoo becomes lighter and lighter, until it is virtually invisible.
Different ink colors respond differently to laser treatment. There are 3 q-switched lasers commonly used on the market today: Ruby, Alexandrite, and Nd:YAG. The ruby was the first q-switched laser and operates at a short wavelength of 690 nm. This makes it effective for blue and green tattoos more than for others, such as black or red. Alexandrite operates at 755 nm and is best for green tattoos. The YAG can be used at both 532 and 1064 nanometers, making it effective against both black and red tattoos, more than the other lasers. There are certain colors that seem more resistant to laser treatment than others, with any laser. These include yellow, pink, and purple.
Each laser tattoo removal treatment is fast. It may take half an hour or more to create a 3 inch tattoo, but a single laser session may last only 30 seconds! Typically, topical anesthetic is placed prior to the treatment or a small area may be injected with local anesthetic. After the treatment, there is sometimes blistering and bruising, but this is not necessary for the treatment to work. Treatments are usually done every 4-6 weeks. A single tattoo might be nearly gone after 3 treatments, but this is scarce. More commonly, tattoos take 6-12 treatments. Some inks are resistant to laser tattoo removal, due to their chemical character. This is the case with metal-oxide tattoo pigments, such as iron and titanium oxides. Although they are nevertheless removable, it takes many more treatments.
These days, laser tattoo removal is effective and safer than ever with the use of q-switched lasers. It does require time and patience for it to work.