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Intense pulsed light photorejuvenation: a histological and immunohistochemical evaluation.

BACKGROUND
The use of intense pulsed light (IPL) for facial rejuvenation had been the topic of many studies. However, few of them discussed quantitative changes in extracellular matrix proteins after IPL therapy.


OBJECTIVE
To objectively quantify the histological changes in extracellular matrix proteins after IPL treatment for facial wrinkles.


METHODS
Biopsy specimens were obtained from the periocular area of six volunteers of Fitzpatrick skin type III-IV and Glogau's class I-III wrinkles. They were subjected to three months of IPL treatment (six sessions at two-week intervals). Using histological and immunostaining analysis coupled with computerized morphometric analysis, quantitative evaluation of collagen types I, III and VII, newly synthesized collagen, total elastin and tropoelastin was performed for skin biopsies at baseline, end of treatment, and three months post-treatment.


RESULTS
Clinical assessment of volunteers did not show clinically noticeable improvement in facial wrinkles after IPL treatment. Furthermore, quantitative evaluation of extracellular matrix proteins showed no statistically significant changes (P>0.05) in response to IPL treatment


CONCLUSION
Although 50 percent of volunteers showed mild improvement in skin texture at the end of IPL treatment, none of them reported improvement in skin tightening or wrinkles. No statistically significant histological changes were observed three months post IPL treatment.