ing 15% L-ascorbic acid, 1% alpha-tocopherol, and 0.5% ferulic acid ± skin exposure to the 1927 nm wavelength (8 passes; 5 mJ/pulse; settings [treatment coverage]: low [5%]; medium [7.5%]; high [10%]), with assessment of permeation via highperformance liquid chromatography.11,12 A dose-dependent uptake of the serum was observed, with an 8-, 12-, and 17-fold increase in enhancement ratios with low, medium, and high energy laser settings, respectively (Figure 3).10-12 In another skin permeability experiment with different donor tissue, compared with skin not exposed to laser treatment, a 5-fold increase in the uptake of the serum was observed with the 1927 nm wavelength handpiece and a 2.7-fold increase with the 1440 nm wavelength handpiece (Figure 4).10 These results indicate that the 1927 nm and 1440 nm handpieces can facilitate delivery of small molecular weight compounds through the skin without compromising the barrier function of the stratum corneum.
Clinical Applications
The 1440 nm and 1927 nm NFDL system has been studied for a wide range of applications. Studies have found a reduction in the number of detectable skin pores and improvement in photodamaged skin, melasma, postinflammatory hyperpigmentation (PIH), and hyperpigmentation (including ethnic/ periorbital) following treatment (Tables 3 and 4).13-20
Skin Texture or Textural Changes
The safety and efficacy of the 1440 nm wavelength handpiece of the NFDL system for improving overall skin appearance and reducing detectable pores was demonstrated in a study in 20 patients14 with Fitzpatrick skin type I–VI.14 Patients received 6 treatments 2 weeks apart (± 3 days) at the highest tolerable energy level (8 passes; 4, 7, or 9 mJ/pulse). Digital imaging was used to determine a pore score (percentage of skin surface with detectable pores). Clinicians and patients also
