Resumen

Objectives: To evaluate the efficacy and safety of QS Nd:YAG (1064 nm) and KTP (532 nm) lasers in cosmetic tattoo removal, including outcomes in resistant cases treated with adjunctive fractional CO₂ laser. Introduction: Cosmetic tattoos present unique challenges for removal due to pigment composition (e.g., iron oxide, titanium dioxide) and risk of paradoxical darkening. Q-switched (QS) Nd:YAG/KTP lasers are the gold standard, but optimal protocols for resistant cases remain debated. Materials / method: Retrospective analysis of 111 consecutive patients (88.3% female; mean age 33.3±7.8 years; Fitzpatrick II–III 94.6%) with cosmetic tattoos (55% monochromatic, 45% multicolor). Treatments used Q-switched 1064 nm (black tattoos: 400–1200 mJ/P, 1–5 mm spot, 1–3 Hz) or 532 nm (colored tattoos: 400–800 mJ/P, 3–4 mm spot, 1–2 Hz). Resistant tattoos (no response after 3 sessions) received combined fractional CO₂ (8–16 W, 1.2–1.6 msec) + QS laser. Primary outcomes: mean clearance percentage and sessions required; secondary outcomes: adverse events (AEs). Results: Mean clearance was 64.1±18.1% after 2.5±1.6 sessions. Limb tattoos (45% of cases) showed comparable clearance to facial tattoos (p=0.12). Resistance occurred in 18% of cases, predominantly in multicolor tattoos (p<0.01); adjunctive CO₂ improved clearance by 32±14% (p=0.003). No keloids or hyperpigmentation were observed. Transient erythema (23.4%) and hypopigmentation (8.1%) resolved within 3 months. Conclusion: QS Nd:YAG/KTP lasers effectively remove cosmetic tattoos, with higher resistance in multicolor pigments. Fractional CO₂ laser enhances clearance in resistant cases without increasing AEs. Protocol standardization (e.g., 4–5-week intervals for eyebrows) optimizes outcomes.