Histologic comparison of microscopic treatment zones induced by fractional lasers and radiofrequency

Abstract

Introduction: Fractional photothermolysis induces microscopic, localized thermal injury in the skin surrounded by undamaged viable tissue in order to promote wound healing. Objective: This study evaluated acute histologic changes following each single pass of various fractional lasers and radiofrequency (RF). Methods: Three male domestic swine were used. We used fractional Erbium:glass (Er:glass), Erbium:yttrium-aluminum-garnet (Er:YAG), CO₂ lasers, and fractional ablative microplasma RF. We analyzed features and average values of the diameter, depth, and vertical sectional areas treated with each kind of laser and RF. Results: The microscopic treatment zone (MTZ) of fractional Er:glass resulted in separation of dermoepidermal junction with no ablative zone. Fractional Er:YAG provided the most superficial and broad MTZ with little thermal collateral damage. Fractional CO₂ resulted in a narrow and deep “cone”-like MTZ. Fractional RF resulted in a superficial and broad “crater”-like MTZ. Conclusions: This study provides the first comparison of MTZs induced by various fractional lasers and RF. These data provide basic information on proper laser and RF options. We think that these findings could be a good reference for information about fractional laser-assisted drug delivery.