Introduction to tattoo removal using lasers

Tattooing is a body art that has enchanted men since time immemorial. And with this exciting art comes its rather unexciting removal process; as humans were born to be fickle and tattoos are also a victim of their changing tastes and hence the necessity for their removal.

The initial tattoo removal methods were abrasive and skin damaging. They caused considerable skin destruction, inflammation (since they involved removing the outer skin layer), scarring and risk of post treatment infection. Dermabrasion or salabrasion, often with chemical accompaniments, were the commonest processes. When the thermal ways of tattoo removal began, there was no respite from skin damage, inflammation and scarring either. Even the use of liquid nitrogen used to target the skin in a nonspecific manner involved risks of scarring and incomplete results. Surgical removals caused large scars as well.

The first non-scarring process became possible with the advent of selective photothermolysis. Lasers began nonselective tattoo removal in the late 1970s. The nanosecond pulse available with Q-switched neodymium:yttrium-aluminum-garnet, alexandrite, and ruby lasers were considered most favorable for effective and non-scarring tattoo removal. The older lasers or intense pulsed light sources cause considerable scarring. The more modern Q-switched lasers have been the biggest boon in laser tattoo removal, coupled with the advancement in tattoo inks and skin clearing mechanisms. There is continuing research regarding the effectiveness of even shorter pulse-duration lasers in tattoo removal.

First generation tattoo removal lasers

Before the advent of selective photothermolysis, tattoos were removed with these initial relatively destructive laser methods.

The continuous argon laser: This is a green or blue continuous laser pulse of 488 and 514 nm. The tattoo pigments that are to be removed from the skin preferentially absorbs the pulses, but since the passes are not too rapid the heat generated in the process also damages the surrounding skin tissues thus causing hyperpigmented scarring. It also results in considerable tattoo pigment leftovers.

The CO2 laser: CO2 laser is almost a quarter of a century old in the tattoo removal process. This uses a pulse of 10,600 nm and removes tattoos nonselectively, by ablating the superficial skin layer with greater control, uniformity and accuracy while targeting the superficial skin layers. However, even the most advanced CO2 laser is not free from inflammation, hypopigmented scarring and attains only partial removal of tattoo pigments

Recent second generation tattoo removal lasers

Modern tattoo needles are designed to penetrate the epidermis and reach the melanin pigment in the middermis of the skin, which has the capacity to preferentially absorb a large spectrum of wavelengths.

Multiple and broad spectrum of wavelengths are necessary so that tattoos that come in a variety of colors now-a-days can absorb the pulses of radiation necessary for their effective removal. This apart, tattoos often become refractory to some wavelengths of laser pulses and hence alternative lasers may be required to remove the residual tattoo pigments.

Herein the size of the laser beam on the skin also has a great bearing on the extent of absorption of laser rays, which is also linked to scarring and side effects.

Color is also a key factor in the effective absorption of lasers for tattoo removal. In the early days of tattoo removal, black was the most common tattoo pigment and since it was capable of absorbing a wide spectrum of wavelength, red or infrared lasers were effectively used for its removal. Red and near-infrared wavelengths were good enough since they penetrated great depths. However, with the availability of variety of tattoos colors later, it was theorized that the color of the tattoo is not ideal for its removal. Hence, it became necessary to use multiple lasers.

The most recent and standard laser tattoo removal involves the Q-switched lasers, which includes very short nanosecond pulses. Intense millisecond pulses cause scarring and only partial tattoo pigment removal. The ruby, alexandrite and neodymium:yttrium-aluminumgarnet (Nd:YAG) lasers are the best Q-switched laser types.

The ruby laser has reported the most effective but also shows the greatest incidence of hypopigmentation. Of course comparative analysis is not foolproof. Ongoing research with even shorter laser pulse durations (like picosecond lasers) than Q-switched type lasers brings future hope of greater effectiveness, lesser side effects and reduction in number of treatment sessions. This has been combined with efforts in advancements in the optical aspects of the procedure and improvement in degree of skin penetration.

Dos and don'ts in the laser removal procedure

There are a few essential aspects of the laser tattoo removal process, which are:

Patient counseling: This is important so far as any patient misconception regarding the procedure, its outcome, the costs, mind blocks, fears, treatment duration and pre and post-treatment care is concerned. The laser sugeon should provide detailed information on how the procedure will work and what to expect.

Treated skin care: This is also vital in order to ensure a safe and effective process. It involves pretreatment, during treatment and post treatment wound care. The laser surgeon should provide detailed information.

Risks from laser removal of tattoos

There are certain snags that may occur during the process and must be safeguarded against. They are:

• Use of the wrong laser apparatus leading to skin damage
• Use of too high an energy pulse, which can result in temporary pigmentary changes and scarring
• An allergic reaction to tattoo pigments that become dispersed during laser treatment
• Skin darkening in the area of the tattoo