Efficacy of 1064‐nm Picosecond Laser in the Treatment of Lichen Planus Pigmentosus: A Split‐Face Randomized Controlled Trial

BACKGROUND: Lichen planus pigmentosus (LPP) is an uncommon variant of lichen planus that causes visible pigmentation and significantly impacts quality of life. Current treatments for LPP are limited, with inconsistent outcomes from topical, oral, and laser therapies. The 1064-nm picosecond laser has shown potential in managing pigmented skin disorders; however, evidence regarding its effect on LPP remains scarce. OBJECTIVES: This study aimed to evaluate the efficacy, safety, and patient satisfaction of the 1064-nm picosecond laser in treating LPP. METHODS: The study was a randomized, split-face controlled trial. Twelve patients with biopsy-confirmed LPP were enrolled, with one side of each participant treated with four sessions of the 1064-nm picosecond laser at monthly intervals. The Modified Dermal Pigmentation Area and Severity Index (mDPASI) and melanin index (MI), assessed by three-dimensional imaging, were measured before each treatment and at 1, 3, and 6 months following the last treatment. Physician global assessment (PGA) and patient satisfaction scores were assessed at 1 and 6 months following the last treatment. Additionally, adverse events were recorded. RESULTS: A total of 12 patients with LPP, aged 55 ± 11.1 years, were recruited, and 11 completed the study. During the 6 months following the end of laser treatment, no significant differences were found in MI, mDPASI, or PGA between treatment and control groups. However, satisfaction scores showed a significant improvement on the treated side compared to the control. The mean overall pain score was 3.70 ± 1.72, with no major adverse events reported. CONCLUSION: The 1064-nm picosecond laser demonstrated limited effectiveness in improving LPP clinical outcomes. Further studies with sham-controlled trials and larger sample sizes are needed to optimize treatment parameters and sessions, and to validate the role of the picosecond laser as a therapeutic option for LPP.