Treatment of photoaging with a very superficial Er:YAG laser in combination with a broadband light source

Journal of Drugs in Dermatology, Nov, 2007 by Alexander L. Berlin, Mussarrat Hussain, Robert Phelps, David J. Goldberg

Abstract

Background and Objective: Studies documenting improvement following combined laser and light-based devices are needed. The objective of this study was to evaluate clinical, histological, and ultrastructural changes in photodamaged facial skin following sequential treatment with ablative superficial erbium:YAG (Er:YAG) laser peels and nonablative intense pulsed light, or broadband light (BBL), treatments.

Study Design/Materials and Methods: Fifteen subjects with photodamaged facial skin and Fitzpatrick skin types I to III underwent 3 monthly treatments with the Profile[TM] system (Sciton, Inc, Palo Alto, CA) utilizing very superficial MicroLaserPeel[TM] settings of 2.5 to 5.0 J/[cm.sup.2] and BBL[TM] settings of 515-, 560-, or 590-nm filters, 10-msec pulse duration, and fluences of 12 J/[cm.sup.2]. Five subjects underwent pre- and post-treatment postauricular skin biopsies for evaluation of treatment-induced light and electron microscopic changes.

Results: Twelve subjects completed the study. Both blinded evaluator and subject assessment of clinical changes documented significant improvement in photodamaged skin, with the greatest improvement achieved in overall appearance and epidermal dyspigmentation. These results were largely maintained at 3 months following the last treatment. Light microscopy showed changes in the epidermis, collagen, and elastic fibers consistent with a wound repair mechanism to the depth of 250 to 350 microns. Electron microscopy revealed a slight decrease in the average collagen fiber thickness, pointing to an increase in type III collagen.

Conclusion: A protocol utilizing multiple combined superficial Er:YAG ablative treatments and nonablative BBL treatments lead to a significant improvement in the clinical signs of photodamaged skin, with histological and ultrastructural evidence of new collagen formation.

Introduction

As various laser and light-based devices are being combined in clinical practice for their additive effect, studies documenting improvement following such treatments need to be undertaken. Both superficial ablative treatments using erbium:YAG laser and nonablative treatments using intense pulsed light (IPL)--also known as broad-band light (BBL[TM])--have been successfully used for facial photorejuvenation. (1,2) In addition to the clinical improvement noted with each of these devices, histological and ultrastructural evidence of new collagen formation and other changes associated with the wound repair mechanism have also been demonstrated. (3) Since both of these treatment options result in minimal, if any, downtime and adverse effects, they represent attractive options for facial rejuvenation.

This study was undertaken in order to evaluate clinical improvement in photodamaged facial skin using multiple sequential very superficial ablative Er:YAG laser peels combined with nonablative full-face BBL treatments. In addition, histological and ultrastructural examination of biopsy specimens was performed to assess the treatment-induced microscopic changes.

Materials and Methods

Fifteen female subjects with photodamaged facial skin, ranging in ages from 30 to 60 years and Fitzpatrick skin types I to III, were enrolled in the study. An explanation of the risks, benefits, and potential complications was given to the subjects, and written informed consent was obtained.

Subjects with a history of herpes simplex in the treatment areas were given prophylactic oral antiviral agents prior to the procedure. Anesthesia was achieved with a topical anesthetic cream applied for 1 hour prior to each treatment. All subjects were then treated using the Profile[TM] multiapplication system (Sciton, Inc, Palo Alto, CA). Specifically, the Er:YAG laser was used in a scanning ablative mode, also known as MicroLaserPeel[TM], with a 6-mm spot size, 2.5 J/[cm.sup.2] for the first session and 5.0 J/[cm.sup.2] thereafter, and 30% pulse overlap to complete one full pass over the entire face. Subsequently, a chilled gel was applied to the face, and the BBL source was used in a nonoverlapping pattern with a 515-, 560-, or 590-nm filter, depending on the level of epidermal dyspigmentation, in a single-pulsed mode with 10-msec pulse duration and fluence of 12 J/[cm.sup.2] using contact cooling.

A petrolatum-based ointment was then applied to the entire face and subjects were instructed on proper wound care. Additionally, the subjects were instructed on proper sun protection and the use of broad-spectrum sunscreens. A total of 3 sessions were performed at 1-month intervals, with additional follow-up visits at 1 and 3 months following the last treatment.

Assessment of clinical improvement was performed using blinded observer evaluation of photographs obtained pre-treatment and at 1 and 3 months following the last treatment. Pre- and post-treatment photographs were randomly placed side by side and the blinded observer was asked to assign the difference, in percents, between the 2 photographs in the following aspects of photodamaged skin: overall appearance, epidermal dyspigmentation, rhytides, and skin laxity. In addition, at 1 and 3 months following the last treatment, subjects completed standardized questionnaires on their perceived percent improvement in the same categories.