A Case of acne scarring treated with Fractional Photothermolysis

ABSTRACT

Acne scarring affects 30% of patients with moderate to severe acne vulgaris. It is particularly common in acne conglobata and acne fulminans. To reduce the incidence of scarring, acne is best treated early. There are various treatments available for acne scars, such as chemical peel, dermabrasion, laser (resurfacing), dermal fillers, punch grafting and subcision therapy. Fractional photothermolysis is a novel technology designed to create a network of microscopic intradermal zones of thermal injury in the dermis and overlying epidermis with islands of spared, normal tissue, using focused beams of infrared laser energy (1550nm). Fractional photothermolysis (Fraxel laser treatment; Reliant Technologies; Palo Alto; California) is currently approved by the US Food and Drug Administration for the treatment of periorbital rhytids and dyspigmentation. The Fraxel laser is a 30watt, diode pumped, 1,550nm erbium fiber laser that targets water as its chromophore. It is a safe and gradual laser procedure that stimulates the body to replace aged and photo-damaged skin, even on delicate skin areas, such as the neck, chest and hands. Utilizing the concept of fractional treatment, 70-100um wide and 250-800um deep, microthermal zones of tissue coagulation are produced. Tissue is not vaporized and the stratum corneum remains intact. The epidermal coagulated tissue is expelled and replaced by keratinocyte migration.When there is a significant damage to the basement membrane zone, the dermal contents are also expelled as microscopic epidermal and dermal necrotic debris. Zone of collagen denaturation in the dermis cause upregulation of the inflammatory cascade, which leads to collagen remodeling and new collagen formation. The mid-infrared wavelength of the Fraxel laser allows deeper penetration into the tissue without the injury observed with traditional ablative laser (such as lengthy downtime, severe pain and prolonged edema). The reported complications are post-inflammatory hyperpigmentation (up to 20%), hypopigmentation, infection and scarring.