Randomized, Double-Blind, Split-Face Study Evaluating Fractional Ablative Erbium:YAG Laser-Mediated Trans-Epidermal Delivery of Cosmetic Actives and a Novel Acoustic Pressure Wave Ultrasound Technology for the Treatment of Skin Aging, Melasma, and Acne Scars

November 2015 | Volume 14 | Issue 11 | Original Article | 1191 | Copyright © November 2015


Macrene Alexiades MD PhDa,b

aAssociate Clinical Professor Yale University School of Medicine
bFounder and Director, Dermatology and Laser Surgery Center, New York, NY

Abstract
BACKGROUND: Fractional laser resurfacing enhances trans-epidermal delivery (TED), however laser penetration depths >250- μm fail to substantively increase drug delivery.
AIM: Evaluate the safety and efficacy of a novel acoustic pressure wave ultrasound device following fractional ablative Er:YAG 2940-nm laser (FELR) and topical agents for rhytids, melasma, and acne scars.
STUDY DESIGN: Randomized, blinded, parallel group split-face side-by-side, controlled study evaluating FELR and topical anti-aging and anti-pigment agents to entire face succeeded by ultrasound to randomized side. Fifteen subjects were enrolled to three treatment arms:rhytids, melasma, and acne scars. Two monthly treatments were administered with 1, 3, and 6 month follow-up. Efficacy was assessed by Comprehensive Grading Scale of Rhytids, Laxity, and Photoaging by Investigator and two blinded physician evaluators. Subject assessments, digital photographs, and reflectance spectroscopic analyses were obtained.
RESULTS: Rhytid severity was reduced from a mean of 3.25 to 2.60 on the 4-point grading scale. Spectrophotometric analysis demonstrated increases in lightness (L*) and reductions in redness (a*) and pigment (b*), with greater improvements on the ultrasound side as compared to FELR and topicals alone. Moderate erythema post-treatment resolved in 7 days and no serious adverse events were observed.
CONCLUSION: In this randomized, paired split-face clinical study, FELR-facilitated TED of topical anti-aging actives with ultrasound treatment is safe and effective with improvement in rhytids, melasma, and acne scars. Statistically significant greater improvement in pigment levels was observed on the ultrasound side as compared to FELR-TED and topical agents alone.

J Drugs Dermatol. 2015;14(11):1191-1198.

INTRODUCTION

Recent research has focused upon the use of fractional laser resurfacing to augment topical drug delivery.1 The main barrier to attaining appreciable clinical results with topical therapy has been the stratum corneum, which blocks the majority of compounds from entering the skin, allowing only smaller (<500 Da) lipophilic molecules to slowly enter.2 In the past, attempts to boost topical compound delivery have included chemical and physical approaches, such as nanocarriers, penetrants, microneedling, electroporation, chemical peeling and stratum corneum stripping. Recently, research has focused upon the use of fractional laser resurfacing to create microscopic channels through the stratum corneum and epidermis to a desired depth to increase topical agent delivery.
An ideal candidate for generating controlled perforations and creating passages of trans-epidermal delivery (TED) for cosmeceuticals is the fractional Er:YAG 2940-nm laser, which is efficiently absorbed by water molecules and may be used to precisely ablate the epidermis to a desired depth with minimal thermal injury.3 Fractional Er:YAG-mediated TED has been used to enhance delivery of analgesics,4,5, narcotics,6 anesthetics, 7 methotrexate,8 imiquimod,9 and aminolevulinic acid for photodynamic therapy.10 Thus, a number of published reports demonstrate the use of fractional Er:YAG laser to facilitate topical delivery of active compounds into the skin.
The degree of drug delivery enhancement following fractional laser is limited by several factors. A systematic histological study demonstrated that while laser fluence was directly proportional to pore depth, it did not directly correlate with drug uptake.11 Bachav and colleagues showed that low energies of fractional Er:YAG laser ranging from 4.5-13.6 J/cm2 resulted