A Pilot Split-face Comparison of Q-switched (QS) Single Pulse versus QS Quick Pulse-to-pulse 1,064-nm Nd:YAG Laser Treatment in a Patient with Melasma

Melasma is a common disorder that clinically presents as symmetric illdefined hyperpigmented macules and patches on the face. In the current split-face, evaluator-blinded study, we treated a female patient with eight sessions of 1,064-nm Nd:YAG laser treatment at one-week intervals. Utilizing the Q-switched (QS) quick pulse-to-pulse (Q-PTP) mode, in reference to the laser settings, 1,064-nm Nd:YAG laser energy can be irradiated at split fluences and at a dual-pulse interval of 80-μsec. On the right side of the face, 1,064-nm QS single pulse Nd:YAG laser treatment was administered with the settings of 1.6 J/cm2, a spot size of 7-mm, and 1200 shots. On the left side, 1,064-nm QS Q-PTP Nd:YAG laser treatment was administered with the settings of 1.6 J/cm2 irradiated at dual pulses of 0.8 J/cm2 at 80-μsec intervals, a spot size of 7-mm, and 1,200 shots. Results of objective clinical assessment showed better clinical outcomes with less treatment-associated pain with QS Q-PTP-treatment than with QS single-pulse-treatment. However, clinical outcomes were subjectively indistinguishable between QS single pulseand QS Q-PTP-treatments. Transient or persistent post-treatment erythema and newly developed punctate leukoderma lesions were not reported for either side of the face. Pre-existing punctate leukoderma lesions became obscure, especially on the QS Q-PTP-treated side, with improvement of the melasma lesions. We suggest that the QS Q-PTP mode may be of use in treatment of melasma, particularly on the relatively thin skin of the periorbital regions and in pain-sensitive and erythema-prone patients.