[Clinical efficacy of Q-switched Alexandrite laser for pigmentary skin diseases in 4656 patients].

Objective To evaluate the clinical efficacy and safety of Q-switched Alexandrite laser in the treatment of pigmentary skin, diseases ( PSDs). Methods Totally 4 656 patients with PSDs were treated with Q-switched Alexandrite laser. These PDSs included nevus of Ota, seborrheic keratosis, tattoo, naevus fusco-caeruleus zygomaticus, cafe-au-lait-spots, lentigo, naevus of Ito, and spilus naevus. The outcomes and adverse events after treatment were oberserved. Results The response rate was 92.31% and the cure rate was 55.39% for nevus of Ota after six times of treatment, and the cure rate was 100% after nine times of treatment. The response rate was 100% for freckles, seborrheic keratosis, and naevus fuscocaeruleus zygomaticus after four times of treatment. The response rate was more than 77.18% and the cure rate was more than 50% for tattoos after three times of treatment, including amateur tattoo, artificial eyebrow, eyelid lines, and traumatic tattoo. However, after four times of treatment, the response rate and the cure rate were only 50. 00% and 21.43% for cafe-au-lait spots, and 50.00% and 25.00% for spilus naevus, respectively. The response rate was 35.29% for lentigo and 25.00% for naevus of Ito/ spilus naevus after four times of treatment. Conclusion Q-switched Alexandrite laser is effective in the treatment of nevus of Ota, seborrheic keratosis, tattoo, and naevus fusco-caeruleus zygomaticus, but has limited efficacy for cafe-au-lait-spots, lentigo, naevus of Ito, and spilus naevus.