Intense pulsed light (IPL) is widely used in treating skin conditions and has been reported to increase collagen and elastic fibers without damaging the epidermis.Objective
To evaluate the effect of variation in the number of passes and intervals of IPL treatments on photorejuvenation in rats.Materials and Methods
Groups of two rats each were exposed to two or four passes of an IPL source using a fluence of 30 J/cm2 and a cut-off filter of 560 nm at 1- or 3-week intervals. The collagen and elastic fiber content in stained tissue biopsies and the thickness of the collagen fibers of IPL-irradiated and unexposed skin regions were compared.Results
Collagen distribution and collagen fiber diameter was in IPL-irradiated than in control regions. The number of passes did not significantly affect the collagen fiber thickness, but the collagen fibers from the 3-week-interval groups were thicker than those of the 1-week-interval groups (p < .001).Conclusion
IPL increased dermal collagen fibers and collagen fiber diameter, suggesting efficacy in photorejuvenation and wrinkle reduction.