Efficacy and safety of picosecond 755-nm alexandrite laser for treatment of nevus of Ota in Taiwanese children: A retrospective study

Objectives To evaluate the efficacy and safety of picosecond 755-nm alexandrite laser in the treatment of nevus of Ota in children. Materials and Methods A retrospective study was conducted by reviewing medical charts and photographs of 86 Taiwanese children with various types of nevus of Ota between January 2017 and September 2020. Picosecond 755-nm alexandrite laser therapy was used to treat pigmentary lesions. Percent clearance of lesions during treatment and the treatment time required to achieve 95%-100% clearance were determined. Results According to Tanino's classification or Peking University Medical College Hospital (PUMCH) classification of nevus of Ota, most patients belonged to Tanino's Type II (32%) and Type III (38%) or PUMCH Type IIb (33%) and Type IIIb (26%), which indicated that the nevus was mainly distributed in the forehead, upper and lower eyelid, zygomatic, cheek, and temple regions. After treatment with picosecond 755-nm alexandrite laser, 96.5% of the patients achieved 95%-100% clearance with an average of 4.3 treatment sessions. The earlier onset of lesions (before 5 months of age) and the darker Fitzpatrick skin types (type IV vs. type III) significantly increased the number of treatments required to achieve clear response, while sex, age at first treatment, Tanino's classification of nevus, and color of nevus had no significant effect. Posttreatment hypopigmentation or hyperpigmentation was transient and resolved within 6 months. No serious response of the skin was evident. Conclusion Picosecond 755-nm alexandrite laser treatment of nevus of Ota in children was safe and effective. The treatment was well-tolerated, and only a few transient, minor side effects occurred.