THE Q-SWITCHED ND-YAG LASER EFFECTIVELY TREATS TATTOOS - A CONTROLLED, DOSE-RESPONSE STUDY

Background and Design: The Q-switched ruby laser was recently shown to remove tattoos without scarring. The Q-switched neodymium: yttrium aluminum garnet (Nd:YAG) laser, which targets black ink with a longer wavelength that has less absorption by melanin, should effectively treat tattoos with fewer pigmentary alterations. A prospective, blinded, controlled study was conducted to assess the ability of the Q-switched Nd:YAG laser (1064 nm, 10 ns, 5 Hz) to remove tattoos. Twenty-five patients with 39 blue-black or multicolored tattoos (14 previously untreated, 25 Q-switched ruby laser-resistant) were exposed in randomly derived quadrants with 6, 8, 10, or 12 J/cm2 at 3 to 4 week intervals for a total of four treatment sessions. Results: An excellent response (> 75% ink removal) was seen in 77% of the black tattoos and more than 95% of the black ink cleared in 11 (28%) of 39 tattoos at 10 to 12 J/cm2 after four treatment sessions. Colored inks were not as effectively removed. Response was related to fluence with greatest improvement noted in the quadrants treated with 10 and 12 J/cm2. No significant side effects, including pigmentary changes or scarring, were noted. Histopathologic examination demonstrated persistence of tattoo ink in clinically clear areas and confirmed the absence of fibrosis and granulomatous changes. Conclusion: The Q-switched Nd:YAG laser (1064 nm) effectively treats black tattoos with an excellent cosmetic outcome. Bright colors were minimally responsive to treatment. Higher doses were more effective and equally well tolerated.