A clinical and histologic prospective controlled comparative study of the picosecond titanium : sapphire (795 nm) laser versus the Q-switched alexandrite (752 nm) laser for removing tattoo pigment

Background: Theory predicts that picosecond lasers should be more effective than the cur rently available nanosecond lasers in removing tattoo ink, In addition to thermal confinement, such pulse widths cause optimal photomech anical disruption of the target. Objective: This study compared the efficacy of the picosecond titanium:sapp hire (795 nm, 500 psec) laser and the Q-switched alexandrite (752 nm, 50 ns ec) laser in the treatment of tattooed guinea pigs Methods: Six albino guinea pigs, each with 6 uniformly 1 cm circular black tattoos, were treated. Three of the tattoos were divided into 2; one half w as treated with the titanium:sapphire laser and the other half with the ale xandrite laser. Fluences used for both lasers were 6.11, 4.24, and 2.39 J/c m(2) with spot sizes of 1.25, 1.5, and 2 mm, respectively. The remaining sp ots served as control. Clinical evaluation and biopsies were performed at b aseline and at 11 and 16 weeks after a single laser treatment. Results: Greater clearance of tattoo was observed in titanium:sapphire lase r-treated areas in 2 of the 4 surviving guinea pigs. In some areas total cl earing was observed after the single titanium:sapphire laser treatment. Cle aring improved with higher fluences. No scarring was present. Histologic re sults showed similar findings. Conclusion: Our findings suggest that the picosecond titanium:sapphire lase r is more effective than the Q-switched alexandrite laser in removing tatto o pigment and may be of significant clinical utility.