Purpose: The purpose of this study was to evaluate the effects of the pulsed dye laser on type-1 collagen and collagenase mRNA transcription in fibroblasts in the papillary and reticular dermis. Methods: Four patients with sun damage were given informed consent for biopsy and laser treatment. Pretreatment periorbital biopsies were taken and fixed in formalin. Two patients then underwent two periorbital treatments 6 weeks apart with the Pulsed Dye Laser set at 585 nm,lO mm spot, 3.5-5 J/cm2. The other two patients were treated with the same time course using the photoderm set at 42 J/c&, 590 nm filter, pulse mode 2, pulse duration 4.5 msec, delay 10 msec. Biopsies were taken at six weeks after the last treatment. The biopsies were embeded in pa&in, sectioned at 4 urn, and stained with DIG labelled mRNA probes for collagen type I and collagenase. The slides were analyzed by light microscopy. Results: Collagen type I showed a 18% increase in transcripts in the papillary dermis after photoderm treatment and a 23% increase with the PDL. Collagenase transcripts were increased 32% with the photoderm and up to 40% with the PDL. Of particular interest was the localized increased expression of transcripts in the papillary dermis after treatment.
Conclusion:
This study demonstrated that subsurface resurfacing with the Pulsed Dye Laser can increase free type-1 collagen and collagenase mRNA in fibroblasts for translation into their respective proteins. This method achieves its results by stimulating the production of extracellular matrix proteins and enzymes by dermal fibroblasts. Breaking down sun damaged collagen and replacing it with newly formed collagen can reduce the appearance of rhytids.