Tattoo removal is a procedure to eliminate or significantly lighten a tattoo from the skin. People pursue removal for many reasons, including changes in personal taste, social or professional considerations, or a desire to relocate a tattoo. Modern techniques include laser removal, dermabrasion, surgical excision, and other methods. The process of tattooing generally creates permanent markings in the skin, but people have attempted many methods to try to hide or destroy tattoos.
The standard modern method is the non-invasive removal of tattoo pigment using Q-switched lasers. Different types of Q-switched lasers are used to target different colors of tattoo ink; depending on the specific light absorption spectra of the tattoo pigments. Typically, black and other darker-colored inks can be removed completely using Q-switched lasers, while lighter colors, such as yellows and greens, are very difficult to remove. Success depends on a wide variety of factors including skin color, ink color, and the depth at which the ink was applied.
Recent research has investigated the potential of multi-pass treatments and the use of picosecond laser technology.
History Before tattoo removal with Q-switched lasers began in the early 1990s, continuous-wave lasers were the standard method for tattoo removal. Continuous-wave lasers used a high energy beam that ablated the target area and destroyed surrounding tissue structures as well as tattoo ink. Treatment tended to be painful and cause significant scarring.
Prior to the development of laser tattoo removal methods, common techniques included dermabrasion, TCA (Trichloroacetic acid, an acid that removes the top layers of skin, reaching as deep as the layer in which the tattoo ink resides), Sal abrasion (scrubbing the skin with salt), cryosurgery, and excision, which is sometimes still used along with skin grafts for larger tattoos. Many other methods for removing tattoos have been suggested historically, including the injection or application of tannic acid, lemon juice, garlic, and pigeon dung.
Saline is used to lighten tattoos (including microblading tattoos) through the process of osmosis.
Motives A poll conducted in January 2012 by Harris Interactive reported that 1 in 7 (14%) of the 21% of American adults who have a tattoo regret getting one. The poll did not report the reasons for these regrets, but a poll that was conducted four years prior reported that the most common reasons were "too young when I got the tattoo" (20%), "it's permanent," "I'm marked for life" (19%), and "I just don't like it" (18%). An earlier poll showed that 19% of Britons with tattoos experienced regret, as did 11% of Italians with tattoos.
Surveys of tattoo removal patients conducted in 1996 and 2006 provided more insight. Of those polled, the patients who regretted their tattoos typically obtained their tattoos in their late teens or early twenties and were evenly distributed by gender. Among those seeking removals, more than half reported that they "suffered embarrassment." A new job, problems with clothes, and a significant life event were also commonly cited as motivations. Tattoos that were once a symbol of inclusion in a group, such as a gang, can make it difficult to gain employment. Tattoos that indicate a significant relationship, such as a spouse, girlfriend, or boyfriend, can become problematic if the relationship ends. Celebrities that have had these kinds of tattoos removed include Angelina Jolie, Eva Longoria, Marc Anthony, and Denise Richards.
Removal by replacement
Some people decide to cover an unwanted tattoo with a new tattoo. A skillful cover-up may completely hide the old tattoo, or it may partially hide the old tattoo, depending on the size, style, colors and techniques used on the old tattoo and the skill of the tattoo artist. Covering up a previous tattoo requires darker tones in the new tattoo to effectively hide the unwanted piece. For tattoos that are especially difficult to cover up, a person may choose to get laser tattoo removal to lighten the ink to make the area easier to cover with a new tattoo.
Laser removal
Tattoo removal is most commonly performed using lasers that break down the ink particles in the tattoo into smaller particles. Dermal macrophages are part of the immune system, tasked with collecting and digesting cellular debris. In the case of tattoo pigments, macrophages collect ink pigments, but have difficulty breaking them down. Instead, they store the ink pigments. If a macrophage is damaged, it releases its captive ink, which is taken up by other macrophages. This can make it particularly difficult to remove tattoos. When treatments break down ink particles into smaller pieces, macrophages can more easily remove them.
Tattoo pigments have specific light absorption spectra. A tattoo laser must be capable of emitting adequate energy within the given absorption spectrum of the pigment to provide an effective treatment. Certain tattoo pigments, such as yellows and fluorescent inks are more challenging to treat than darker blacks and blues, because they have absorption spectra that fall outside or on the edge of the emission spectra of the tattoo removal laser. Recent pastel-cultured inks contain high concentrations of titanium dioxide, which is highly reflective. Such inks are difficult to remove because they reflect a significant amount of the incident light energy out of the skin.
The gold standard of tattoo removal treatment modality is considered to be laser tattoo removal using multiple separate Q-switched lasers (depending on the specific wavelengths needed for the dyes involved) over a number of repeat visits. There are several types of Q-switched lasers, and each is effective at removing a different range of the color spectrum. Lasers developed during or after 2006 provide multiple wavelengths and can successfully treat a much broader range of tattoo pigments than previous individual Q-switched lasers. Unfortunately the dye systems used to change the wavelength result in significant power reduction such that the use of multiple separate specific wavelength lasers remains the gold standard.
The energy density (fluence), expressed as joules/cm2, is determined prior to each treatment as well as the spot size and repetition rate (hertz). To mitigate pain the preferred method is simply to cool the area before and during treatment with a medical-grade chiller/cooler and to use a topical anesthetic. During the treatment process, the laser beam passes through the skin, targeting the ink resting in a liquid state within. While it is possible to see immediate results, in most cases the fading occurs gradually over the 7–8 week healing period between treatments.Kirby W, Holmes E, Desai A, Desai T. Best Clinical Practices in Laser Tattoo Removal: Tips for improving patient outcomes and managing patient expectations. The Dermatologist, June 2012: 23-28.
Q-switched lasers are reported by the National Institutes of Health to result in scarring only rarely. Areas with thin skin will be more likely to scar than thicker-skinned areas.
By 2023, the laser tattoo removal market is expected to grow 12.7% annually.
Mechanism of laser action Experimental observations of the effects of short-pulsed lasers on tattoos were first reported in the late 1960s by Leon Goldman and others.Goldman L. et al. Effect of the laser beam on skin. J Invest Dermatol. 1963;40: pp. 121–122. In 1979 an argon laser was used for tattoo removal in 28 patients, with limited success. In 1978 a carbon dioxide laser was also used, but because it targeted water, a chromophore present in all cells, this type of laser generally caused scarring after treatments.Kirby, William, Desai, Alpesh, Desai, Tejas, Kartona, Francisa, Tattoo Removal Techniques: Effective Tattoo Removal Treatments - Part 1, Skin and Aging, September 2005.
In the early 1980s, a new clinical study began in Canniesburn Hospital's Burns and Plastic Surgery Unit, in Glasgow, Scotland, into the effects of Q-switched ruby laser energy on blue/black tattoos.Reid W.H., McLeod P.J., Ritchie A., Ferguson-Pell M. Q-switched ruby laser treatment of black tattoos. British Journal of Plastic Surgery, 1983, 36, 455-459. Further studies into other tattoo colors were then carried out with various degrees of success. Research at the University of Strathclyde, Glasgow also showed that there was no detectable mutagenicity in tissues following irradiation with the Q-switched ruby laser.Newstead J. Assessment of laser/skin interactions by histologic and cytogenetic techniques. Ph.D. Thesis, University of Strathclyde, Glasgow. 1988. This essentially shows that the treatment is safe, from a biological viewpoint, with no detectable increase in the risk of the development of cancerous cells.
It was not until the late 1980s that Q-switched lasers became commercially practical with the first marketed laser coming from Derma-lase Limited, Glasgow. One of the first American published articles describing laser tattoo removal was authored by a group at Massachusetts General Hospital in 1990.
Tattoos consist of thousands of particles of tattoo pigment suspended in the skin.Kilmer SL, Garden JM. Laser treatment of pigmented lesions and tattoos. Semin Cutan Med Surg. 2000 Dec;19(4):239. While normal human growth and healing processes will remove small foreign particles from the skin, tattoo pigment particles are too big to be removed automatically. Laser treatment causes tattoo pigment particles to heat up and fragment into smaller pieces. These smaller pieces are then removed by normal body processes. Q-switched lasers produce bursts of infrared light at specific frequencies that target a particular spectrum of color in the tattoo ink. The laser passes through the upper layers of the skin to target a specific pigment in the lower layers.
Laser tattoo removal is a successful application of the theory of selective photothermolysis (SPTL). However, unlike treatments for blood vessels or hair, the mechanism required to shatter tattoo particles uses the photomechanical effect. In this situation the energy is absorbed by the ink particles in a very short time, typically nanoseconds. The surface temperature of the ink particles can rise to thousands of degrees but this energy profile rapidly collapses into a shock wave. This shock wave then propagates throughout the local tissue (the dermis) causing brittle structures to fragment. Hence tissues are largely unaffected since they simply vibrate as the shock wave passes. For laser tattoo removal the selective destruction of tattoo pigments depends on four factors: The color of the light must penetrate sufficiently deep into the skin to reach the tattoo pigment. Pigments deeper in the skin are harder to remove than those near the surface. The color of the laser light must be more highly absorbed by the tattoo pigment than the surrounding skin. Different tattoo pigments therefore require different laser colors. For example, red light is highly absorbed by green tattoo pigments, while yellow tends not to absorb light. The time duration (pulse duration) of the laser energy must be very short, so that the tattoo pigment is heated to fragmentation temperature before its heat can dissipate to the surrounding skin. Otherwise, heating of the surrounding tissue can cause burns or scars. For laser tattoo removal, this duration should be on the order of nanoseconds. Sufficient energy must be delivered during each laser pulse to heat the pigment to fragmentation. If the energy is too low, the pigment will not fragment and no removal will take place.
Q-switched lasers are the only commercially available devices that can meet these requirements.Kilmer SL. Laser treatment of tattoos. Dermatol Clin. 1997 Jul;15(3):409–17.