Usefulness of picosecond pulse alexandrite laser treatment for nevus of Ota.

Background and aims: Recently, novel picosecond pulse duration lasers (ps-lasers) have been developed for the treatment of multicolored and recalcitrant tattoos, and safety and efficacy have been reported. We therefore hypothesized that ps-lasers could be an alternative treatment for dermal pigmented lesions. We performed a retrospective review to evaluate the efficacy and safety of the ps-laser for nevus of Ota.

Subjects and methods: A retrospective photographic review of 15 patients with nevus of Ota was performed (ages from 10 months to 65 yr). The patients were treated in the Ohshiro Clinic with a picosecond-domain 755 nm alexandrite laser (ps-Alex laser) from June 2015 to August 2017. Improvement was evaluated as the percentage of pigmentation clearance comparing the baseline findings with those at 3 months after the final treatment using a four category grading scale: Poor, 0-24%; Fair, 25-49%; Good, 50-74%; and Excellent 75-100% improvement. Adverse events were also assessed.

Results: All patients obtained clinical improvement ranging from fair to excellent. All 5 patients whose primary treatment was the ps-Alex laser obtained excellent in 2-3 treatment sessions (average 2.5 sessions), and the average total treatment span was 10.0 months. Treatment with the ps-Alex laser caused transient hyperpigmentation followed by improvement to complete resolution at 3 months of follow-up.

Conclusions: Our results suggest that 755 nm ps laser treatment is efficacious for the treatment of nevus of Ota with minimum adverse events.