Fundamental Principles for Laser Tattoo Removal

 Key considerations for ensuring optimal laser tattoo removal outcomes include skin type, nature and color of tattoos, and careful selection of laser parameters, according to a comprehensive, literature-based overview of laser tattoo removal published in Dermatologic Therapy.

Considerations for Laser Tattoo Removal

In their paper, dermatology experts from the Universitas Hasanuddin in Indonesia indicate that there are several considerations involved in laser parameters with laser tattoo removal. These parameters include pulse width, fluence, spot size, and repetition rate. In terms of pulse width, the researchers wrote that a minimum of nanosecond pulse is necessary to achieve an optimal tattoo removal with a laser approach.

They also noted that high fluence of energy density is needed in laser tattoo removal of faded tattoos “or when the amount of target chromophore is less while low fluence is used in tattoos with intense color or layered tattoos.” According to the study authors, it is recommended to choose the lowest fluence that is effective for achieving immediate whitening. Clinicians can increase fluence in subsequent sessions as the density of the ink decreases.

For recommendation on spot size, the investigators wrote that a larger spot size is associated with greater photon preservation and increased dermal penetration, ultimately reducing the risk for epidermal injury. In regard to repetition rate, the writers of the paper note that a high rate of repetition is employed in broad and flat lesions to reduce the duration of therapy, whereas low repetition rates are used in cases that need high levels of precision.

Before Intervention

Before removal, experts agree that clinicians should first determine whether a tattoo was created by a professional tattoo artist or an amateur artist. This may help gauge differences in ink composition, depth, and density. These factors may predict the number of therapies needed, with professional tattoos often requiring more sessions compared with amateur varieties.

In addition, the age of the tattoo should be determined before intervention, as older tattoos may require fewer sessions due to ink fading. The number of colors in a tattoo should also be determined, as tattoos with more than 1 color may require the use of more than 1 wavelength. Clinicians should also identify whether the patient developed an allergy during the making of the tattoo, as the allergy may recur during laser tattoo removal.

To predict the number of laser tattoo removal sessions needed for any given patient, the study authors suggest the Kirby-Desai scale be used. This scale includes domains for Fitzpatrick skin type, tattoo location and color, amount of ink in the tattoo, scar tissue, and whether the tattoo is a layered tattoo.

Test spots should also be conducted before a full session, especially in patients with dark skin who are prone to hyper- and hypopigmentation. This test spot can be assessed after 4 to 6 weeks for pigmentation issues as well as efficacy.

Types of Lasers

The Quality-switched (QS) Ruby lasers appear to be the most commonly used option with the best evidence to support their use in laser tattoo removal. Newer approaches including picosecond (PS) lasers as well as combination and multipass therapy may also be effective for ensuring tattoo clearance without excessive adverse events. The desired response from both lasers is immediate whitening.

Laser Wavelength Recommendations by Tattoo Color

For dark blue and black tattoos, the researchers made suggestions based on Fitzpatrick skin types. For patients with Fitzpatrick skin types 1 to 3, experts suggest QS and PS lasers with 694, 755, and 1064 nm wavelengths as effective for laser tattoo removal. In contrast, patients with higher Fitzpatrick skin types 4 to 6 should receive longer wavelengths of 1064 nm, as this will minimize the risk for epidermal injury.

Although the study authors noted treatment could be initiated with 1064 nm wavelength regardless of color, they made specific wavelength suggestions for other ink colors:

·   Red – 532 nm

·   Green – QS 694 to 755 nm

·   Cosmetic/nude – multiple sessions of 1064 nm (after successful test spot)

Post-Treatment Considerations

Pain and edema are often observed following laser tattoo removal, but clinicians can generally manage these events with cold compression. Patients should be advised to avoid sun exposure and apply emollients and bandages on the treated area for a minimum of 7 to 10 days following the procedure. Clinicians should conduct a follow-up assessment at approximately 4 weeks.

Reference

Kurniadi I, Tabri F, Madjid A, Anwar AI, Widita W. Laser tattoo removal: Fundamental principles and practical approach. Published online October 17, 2020. Dermatol Ther. doi:10.1111/dth.14418