Chapter 11 - Skin Rejuvenation Using Fractional Photothermolysis: Efficacy and Safety

Abstract

Publisher Summary This chapter discusses skin rejuvenation using fractional photothermolysis. Skin rejuvenation is a term used to define a procedure that can reduce the signs of aging and photodamage. Skin rejuvenation using the concept of fractional photothermolysis is a safe and effective treatment modality. Creating microscopic lesions in the epidermis and dermis can lead to expulsion of necrotic debris and dermal collagen remodeling that correlates with improvement in dyschromia, wrinkles, texture, and scarring, with minimal downtime and side effects. Many fractional lasers may also be used for nonfacial resurfacing of the neck, chest, and hands, unlike traditional ablative devices. The principle behind fractional photothermolysis is the formation of isolated and microscopic thermal wounds that are surrounded by zones of spared, viable tissue in a geometrical pattern that does not depend on chromophore distribution. Fractional photothermolysis is distinct from selective photothermolysis. With selective photothermolysis, certain wavelengths are chosen that are specifically absorbed by target structures. The laser energy is then converted into heat, destroying these target tissues, while leaving the surrounding tissues undisturbed. Both selective photothermolysis and fractional photothermolysis produce an adjustable three-dimensional microscopic thermal injury with the width and depth of the lesion dependent upon the parameters selected. In fractional photothermolysis, using an infrared wavelength, these microscopic tissue injuries are also referred to as microscopic thermal zones or MTZs. The MTZs are columns of coagulated tissue that extend from the epidermis down to the mid-dermis with sections of noncoagulated viable tissue between the columns.