For as long as tattoos have existed, so has humanity’s ability to cast doubt over its decisions. To this day, the permanent nature of tattoos represents a caveat for many unsure about getting one.
Across many millennia, several techniques of tattoo removal have emerged. From dermabrasion, and surgical excisions, to the advent of laser technology. Their dramatic evolution, a testament to human wit and the unstoppable advancement of the medical field.
Considered one of the most outdated tattoo removal techniques there are, physicians long performed dermabrasion with metal or diamond-coated fraises.
However, as dermabrasion typically involved rubbing a diamond fraise wheel or a wire brush over skin that was hardened beforehand with a topical cryogen, this invasive method irreparably damaged the patient’s skin.
Furthermore, this technique also put the physician at risk. Dermabrasion caused a patient’s tissue and blood particles to be violently expelled and suspended in air. This increased the risk of contracting airborne diseases.
Although this procedure usually only required a single treatment, physicians could also choose to perform dermabrasion through several sessions to minimize scarring. However, some degree of damage to the skin was still visible in all cases.
Another preferred technique of dermabrasion included the use of abrasive salts, which the physician rubbed onto the patient’s skin until producing inflammation. This reaction was a necessary part of the procedure as it injured the cells which held the tattoo ink particles.
Shortly after, the physician covered the treated area with wound dressings meant to procure further inflammation, therefore removing the ink pigments more effectively.
Other than scarring, individuals who subjected themselves to dermabrasion were at high risk of developing hypertrophy, a condition in which injured skin becomes thicker and raised due to a growth in cell size.
Dermabrasion patients were also prone to developing keloids, another overgrowth of scar tissue which can produce itchiness, pain, and affect the movement of the skin.
This procedure consisted of removing the tattooed skin in its totality with a sharp tool. After the incision was closed with sutures and healed, a linear surgical scar appeared where the tattoo once was.
While efficient, the larger the design, the more likely the patient would have to be subjected to multiple surgeries to remove their tattoo completely.
Moreover, performing surgical excision became increasingly risky if working on areas such as the palm of the hands and the soles of the feet, where the skin is not as flexible as in the rest of the body. This meant movement usually became restricted once the procedure ended due to said loss in elasticity.
While this method might seem a thing of the past, it’s the only alternative for tattoo removal in certain special cases. For instance, those who are allergic to ink pigments and are unable to resort to modern treatments like laser removal. This happens because laser treatments can trigger an anaphylactic reaction, that is, a sudden and life-threatening allergic reaction.
Nevertheless, a steady evolution in technology over the years opened the possibilities for less destructive tattoo removal procedures such as laser treatments, but how did they come to be?
The Goldman Method: First Steps towards Modern Tattoo Removal
In 1961, American Dermatologist Dr. Leon Goldman made history by becoming the first researcher to treat melanoma, a type of cancer that forms on the skin, with lasers. Five years later, he would supervise the first removal through laser surgery of a tumor.
By then, it had become apparent that the capability of lasers to cut into skin and cauterize blood vessels simultaneously, would allow the new technology many different applications. Tattoo removal was among them.
In 1967, Goldman oversaw the first laser tattoo removal session in history. To perform the procedure, the physician used an ND: YAG laser and a 694 Ruby laser. As Time Magazine reported in October of the same year, the laser treatment removed the tattoo ink pigments by creating bursts of hot vapor over the skin.
In 1983, physicians Rox Anderson and John Parrish, colleagues at Harvard Medical School, opened the door for the improvement of the therapeutic use of lasers and other light sources, through their selective photo-thermolysis theory.
Said theory proposed that by using a specific laser wavelength, it was possible to target the destruction of a group of molecules. This allowed for a better localization of thermal energy, meaning the tissue which surrounded the ink particles would not bear damage contrary to Goldman’s method.
However, even by Anderson’s admission, the procedure was only effective around 75% of the time. Moreover, it could require up to 20 monthly sessions to achieve the desired results, elevating the cost of the procedure to thousands of dollars per each session.
Nevertheless its limitations, it had become obvious that laser treatments would be the best way to move towards a non-destructive tattoo removal procedure. At the same time, other researchers were hard at work developing alternative laser tattoo removal methods.
Carbon Dioxide Laser and Other Non-Selective Thermal Methods
A popular tattoo removal method since the 1980s, carbon dioxide lasers target the water molecules found in the skin. They emit an infrared laser beam at a wavelength of 10,600 nm (nanometers). It’s important to note that the shorter the laser range, the safer it is for individuals who go through the treatment.
However, this method heated the tattooed area in a non-specific manner, meaning it was incapable of singling out ink particles, destroying all superficial layers of the skin. Scarring was a common side-effect of the procedure.
Furthermore, although admittedly more effective than other non-selective thermal methods, this procedure only partially removed the tattoo in most cases.
Similarly, the argon laser is another method of tattoo removal which destroys skin tissue through non-selective heating. Nevertheless, it emits a green or blue laser beam at a shorter wavelength of 488 or 514 nm. Just like the carbon dioxide laser, this method scars the skin that is subject to treatment.
Even though heat is the preferred technique when it comes to treating skin conditions, low temperatures have also proven to be somewhat effective in removing tattoos. Such is the case of cryosurgery, where liquid nitrogen is applied onto the tattooed area to freeze it, and then peeling is induced.
It takes several sessions for this technique to achieve noticeable results, and it can produce adverse effects like blisters, ulcers, and permanent discoloration of the skin.
Q-Switched Tattoo Removal Lasers
But what made it so difficult to target ink particles without damaging the skin surrounding them? The presence of melanin pigments within the skin is one of many factors to take into consideration.
As Dermatologist Eric F. Bernstein put it “Melanin pigment is predominately made to absorb ultraviolet radiation, and although its ability to absorb light decreases with increasing wavelength, melanin absorption is still a clinical problem for tattoo removal well into the infrared wavelengths.”
Moreover, as Bernstein points out, tattoos can also become resistant to certain laser wavelengths, similarly to how bacteria becomes resistant to antibiotics. This means that to remove even a single color of ink, such as black, multiple wavelengths of light might be required for tattoo removal to be effective and leave no scarring.
In other words, for laser treatment to be non-destructive, natural chromophores (the part of a molecule responsible for its color) like hemoglobin, melanin, and water, should not be targeted. Instead, tattoo removal lasers should focus their energy on synthetic chromophores, such as tattoo ink found in cells.
This is where Q-switched lasers, popularized in the 90s and developed by Dr. Rox Anderson, come into play. With varying red and infrared wavelengths that range from 532, 694, 755, and 1064 nm and pulsations that last less than 2 nanoseconds, they can penetrate the skin deeper, past the aforementioned natural chromosomes and directly into the ink particles.
As these particles break down under heat, the color pigments are engulfed by white blood cells, which are then absorbed by small glands known as lymph nodes, and ultimately expelled through the liver.
Picosecond Lasers: Going One Step Ahead Of the Q-Switch
Finally, the latest iteration in laser tattoo removal procedures is the picosecond laser. With a lower exposure time than Q-switched lasers, picosecond lasers allow for a more localized heating of ink particles. Their quick pulsations also eliminate the risk of damaging the surrounding skin tissue.
In 1998, a comparative study regarding the effects of the Q-switched and picosecond lasers found that the latter bore more significant results than the former in 12 out of 16 observed participants.
Another study, published in 2012, recorded picosecond lasers cleared at least 75% of blue and green ink pigments after one or two sessions. When it comes to wavelength resistant tattoos, a third investigation from 2015 established near-complete clearing of the tattooed area in 15 out of the 37 participants who went through previous nanosecond laser treatments without satisfactory results.
Although modern tattoo removal still isn’t a completely painless experience, with the advent of picosecond lasers, which have already significantly reduced the length of the procedure, there’s no telling what laser technology will achieve over the next couple of years down the line.