Intense Pulsed Light Photorejuvenation: A Histological and Immunohistochemical Evaluation
November 2011 | Volume 10 | Issue 11 | Original Article | 1246 | Copyright © November 2011
Moetaz El-Domyati MD,a Tarek S. El-Ammawi MD,a Osama Moawad MD,b Walid Medhat MD,a, c Mỹ G. Mahoney PhD,c Jouni Uitto MD PhDc
a Department of Dermatology, Al-Minya University, Al-Minya, Egypt b Moawad Skin Institute for Laser, Cairo, Egypt c Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, PA
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.
J Drugs Dermatol. 2011;10(11):1246-1252.
Different laser and light-based systems have been described for skin photorejuvenation, including ablative and nonablative therapies.1-3 Nonablative photorejuvenation has been classified into two types: Type 1 is for treatment of visible ectatic vessels and pigmentation, while Type 2 photorejuvenation relates to dermal remodeling for wrinkle improvement and/or skin texture and tightening.4, 5
There are two proposed hypotheses elucidating how nonablative photorejuvenation devices might elicit their effects: 1) dermal water absorbs light energy, causing a direct thermal effects on the dermal matrix; 2) the light energy is absorbed by other chromophores (such as hemoglobin, melanin, or both) triggering the release of cellular mediators and growth factors from cutaneous vessels or adnexal structures. Both would give rise to increased dermal temperature, leading to fibroblast activation with subsequent new collagen deposition and dermal matrix remodeling.2, 6
Intense pulsed light (IPL) is one of the light-based technologies used for skin rejuvenation, producing light energy in the visible and mid-infrared ranges of the electromagnetic spectrum.7 It was first introduced in 1992 and was cleared by the US Food and Drug Administration (FDA) in late 1995.8, 9 IPL is a noncoherent polychromatic filtered flashlamp source producing light energy in a broad band wavelength spectrum (400–1200 nm).10 However, a defined wavelength band could be allowed to penetrate the skin and target specific structures by the use of certain cutoff filters.11, 12
Although evidence-based, peer-reviewed publications discussing the effect of IPL at the histopathological level are few, the use of IPL for skin rejuvenation has been rapidly increasing. This study focused primarily on the evaluation of the clinical effects coupled with objective quantification of the corresponding histological changes after IPL treatment for facial photorejuvenation with emphasis on wrinkle effacement.
The present study was conducted on six female volunteers with Fitzpatrick skin types III–IV and Glogau class I–III wrinkles13 (age range: 37–52 years; mean±SD: 44.1±5.2) attending the dermatology outpatient clinic at Al-Minya University Hospital, Al-Minya, Egypt for facial photorejuvenation. All subjects gave an informed consent for study participation and photographs