How to perform ablative laser surgery for skin resurfacing?

The word laser is an acronym for “light amplification by stimulated emission of radiation.” Throughout the past halfcentury, the better understanding of cutaneous physiology and laser technology has substantially improved to provide a sophisticated perspective for laser-skin interactions. Basic knowledge of the fundamentals of laser physics is essential to understanding laser devices. Ablative lasers lead to the controlled removal of the outer layer of the skin along with various degrees of heat formation within the dermis. Ablative lasers have proven efficacy for skin rejuvenation hence commonly used in aesthetic dermatology. Additionally, they are increasingly implemented into medical dermatology for various skin disorders' management. This study aimed to reveal the basic information in using ablative lasers and illustrate the numerous indications based on the physician’s creative potential. The theory of “selective photo-thermolysis” of Anderson and Parish in 1983 is a mile-stone for laser physics. According to this theory, thermal damage can be confined to a selected target within the exposed tissue. This target is determined by laser device wavelength and may include hemoglobin, melanin, exogenous pigment, or water. The target chromophore of ablative lasers is water. Three criteria must be fulfilled to sustain a pure ablation effect during laser applications and eliminate heat generation within the tissue. First, the target chromophore (water) must more avidly absorb the given wavelength than the surrounding tissue. Second, the duration of laser exposure (pulse duration) must be less than the thermal relaxation time of the exposed tissue. Third, laser procedures must be applied with sufficient high-energy settings to yield ablation. The ablative lasers in dermatologic practice include carbon dioxide (CO 2 ) and Erbium:yttrium-aluminum-garnet (Er:YAG) lasers, which emit light in the infrared spectrum. The exposed tissue rapidly heats due to the preferential absorption of energy by intracellular water, which leads to vaporization. The wavelength of the Er:YAG laser (2940 nm) is closer to the absorption peak of water (3000 nm) compared to that of the CO 2 laser (10,600 nm). Consequently, during Er:YAG laser applications, almost all energy is absorbed in the epidermis and papillary dermis, yielding superficial ablation with less accompanying thermal tissue damage and thermocoagulation. Contrarily, heat generation and coagulation are prominent features of CO 2 laser applications. Extreme heat generation is avoided during ablative laser surgeries to diminish ominous long-term complications, such as postinflammatory hyperpigmentation and scarring. However, heat generation can be beneficial and/or are required for certain conditions since the thermal effect stimulates collagen production and provides hemostasis. Conventional Er:YAG lasers lead to almost pure ablation with minimal thermal damage; however, coagulation can be acquired to a certain degree by novel devices by increasing pulse duration. Even by adjusting laser parameters, Er:YAG lasers are Tips for interventional dermatology Girişimsel dermatolojide püf noktaları Çalışkan and Botsalı. How to perform ablative laser surgery?