Use of a picosecond pulse duration laser with specialized optic for treatment of facial acne scarring.

IMPORTANCE: Fractional laser technology is routinely used in the treatment of acne scarring, with thermal injury resulting in collagen synthesis and remodeling. Use of a picosecond pulse duration with a diffractive lens array may be a new technologic advancement in the treatment of acne scarring.

OBJECTIVE: To investigate the safety and efficacy of a 755-nm alexandrite picosecond pulse duration laser with diffractive lens array for the treatment of facial acne scarring.

DESIGN, SETTING, AND PARTICIPANTS: This single-center, prospective study performed in a private practice with a dedicated research department included patients with clinically diagnosed scarring secondary to inflammatory or cystic acne.

INTERVENTIONS: Patients received 6 treatments with a 755-nm picosecond laser with a spot size of 6 mm, fluence of 0.71 J/cm2, repetition rate of 5 Hz, and pulse width of 750 picoseconds in combination with a diffractive lens array, allowing for greater surface area and pattern density per pulse.

MAIN OUTCOMES AND MEASURES: The pain and satisfaction scores for overall appearance and texture were recorded. Masked assessment of clinical photographs and analysis of 3-dimensional volumetric data were performed. Biopsy specimens were obtained for independent histologic evaluation by 2 investigators at baseline and at 3 months after last treatment.

RESULTS: Fifteen women and 5 men (mean age, 44 years; age range, 27-61 years) with Fitzpatrick skin types I through V and facial acne scarring were enrolled. The mean pain score was 2.83 of 10. Patients were satisfied to extremely satisfied with improvement in appearance and texture at their final treatment and follow-up visits. The masked assessment scores of 17 patients were 1.5 of 3 and 1.4 of 3 at 1 and 3 months, respectively (a score of 0 indicates 0%-25% improvement and a score of 3 indicates >75% improvement). A 3-dimensional analysis revealed a mean 24.3% improvement in scar volume, maintained at 1 (24.0%) and 3 (27.2%) months after treatment. Histologic analysis revealed elongation and increased density of elastic fibers, with an increase in dermal collagen and mucin.

CONCLUSIONS AND RELEVANCE: Treatment of facial acne scars with a diffractive lens array and 755-nm picosecond laser produced improvement in appearance and texture at 3 months after the last treatment, with objective findings similar to those published for a series of fractional ablative laser treatments. Histologic findings suggest that improvement in scarring from this treatment goes beyond remodeling of collagen.