Dual Toning Method with the Combination of Picosecond and Microsecond Nd:YAG in Refractory Melasma Unresponsive to Picosecond Alone.

Melasma is an acquired and treatment-resistant aging facial skin condition prevalent among the older Asian females. The Q-switched toning laser is the most widely used for the treatment of moderate to severe melasma in Asia. Recently, the picosecond laser has been introduced for various pigmentary disorders such as melasma. We evaluated the efficacy and safety of dual toning combined with 1064 nm Nd:YAG picosecond and quasi-long-pulsed laser in the treatment of severe melasma.Twenty Vietnamese females, mean age 41.9 ± 6.4 years, Fitzpatrick skin type IV, with clinical diagnosis of severe dermal and mixed-type melasma were treated by at least eight sessions picosecond Nd:YAG 1064 nm reducing Melasma Area and Severity Index (MASI) to less than 15%. Then they were treated with 3 sessions of dual toning combined picosecond Nd:YAG 1064 nm laser having an energy and spot size of 0.6-0.8 J/cm2 and 8 mm with micropulsed mode Nd:YAG 1064 nm laser (350 µs) having an energy and spot size of 2.6 J/cm2 and 15 mm with ICD off. Mild and even erythema was the endpoint (40-42°C using the infrared thermometer). Treatments were given every 4 weeks. Improvement was rated by MASI at the baseline (T1), after eight sessions of picotoning (T2), and three sessions of dual toning (T3).The mean MASI score of 20 patients at baseline (T1) was 16.24 ± 4.88 (min 6.0; max 28.8); after at least eight picotoning sessions, the mean MASI was 15.12 ± 4.69, representing a 7.44 ± 4.41% reduction in MASI score. The MASI score of the dual toning laser continued to decrease after three dual toning sessions from 15.12 ± 4.6 to 9.77 ± 3.86 (MASI score reduced by a mean of 5.35 ± 2.64), achieving 35.15 ± 13.51% reduction from T2 and 40.17 ± 12.14% reduction from baseline MASI (T1). There were no unexpected side effects in any patients.The dual toning method using the 1064 nm Nd:YAG picosecond and microsecond laser was safe and effective and well tolerated by all patients without downtime. However, larger number of studies should be conducted with more objective measurement techniques to confirm the results of this preliminary study.