Evaluation of histologic and electron microscopic changes after novel treatment using combined microdermabrasion and ultrasound-induced phonophoresis of human skin

Background: Mechanical exfoliation using microdermabrasion has been used as a minimally invasive treatment of photodamage, as well as to improve absorption of topical agents. Phonophoresis, a method of electrically assisted percutaneous delivery of macromolecules, relies on ultrasonic waves producing alterations within the stratum corneum that result in increased absorption. Objective: To determine the effects on photodamaged facial skin that resulted from the ultrasound-enhanced delivery of a combined hyaluronic acid, retinol, and peptide-containing complex following microdermabrasion. Methods: Seven individuals, aged 40-65, with Fitzpatrick skin types I-III and class I-III rhytids, underwent eight weekly aluminum oxide crystal microdermabrasion procedures (Parisian Peel (R); Aesthetic Technologies, Golden, CO, USA), followed by administration of a topical combined hyaluronic acid, retinol, and peptide-containing complex, propelled through ultrasound phonophoresis. The participants continued manual twice-daily application of the topical complex between treatments. Clinical evaluation included digital photography, and patient and investigator assessment of changes in skin dryness, texture, brightness, tone, and rhytids. The 3-month post-treatment histologic evaluation consisted of pre- and post-treatment biopsies evaluated for microscopic and ultrastructural changes. Results: An overall mild clinical improvement in the skin was noted. A slight increase in vascularity within the papillary dermis, increased reticulin stain (type III collagen), and ultrastuctural evidence of increased type I collagen indicate dermal injury with resulting new collagen formation. Conclusion: Microdermabrasion followed by ultrasonic phonophoretic application of topical products represents a novel dermal delivery approach to photorejuvenation.