Resumo

Objectives: Over the last 30 years, laser technologies in medicine have predominantly used a single laser beam to irradiate tissues, occasionally in a sequential mode of radiation. Until recently, with the invention of the binary medical laser, there were no medical lasers on the market able to emit two or more laser beams simultaneously to irradiate a tissue target. This new simultaneous (or binary effect) of energy delivery to a treatment target, shows significant advantages in many medical fields compared with a single beam energy source. Introduction: The authors present human skin histological results of the laser that is able to deliver two beam wavelengths of 1550 nm and 1927 nm simultaneously, and in any energy ratio between those two wavelengths. The study design compares four major groups of human skin histology irradiated with laser beams in the following modalities: Simultaneous beam delivery; Sequential beam delivery; Single beam delivery; and Control. Two powerful laser diodes of 1550 nm and 1927 nm directly placed into the laser handpiece emits light directly to the skin surface; spacing 0.5 mm ranging 0.5/1.0/1.0/2.0 mm. Materials / method: Study on the low abdominal skin area prior to abdominoplasty. Area was divided into 12 squares of 3x3cm including simultaneous, sequential, single beam. Post surgical skin harvested for histology. Sirius red + Hematoxylin staining was used to analyze collagen fibers and cells status in regular and polarized light, while a histochemical Weigert method (Resorcinol-Fuchsin dyes) was used to highlight the elastic fibers. Results demonstrated significant differences in depth of laser radiation effect to skin collagen and elastic fibers between simultaneous, sequential and single beam radiation. Results: A single beam of radiation at 1550nm penetrates into the skin up to 150-250 microns (contingent upon pulse energy of 35-45mJ). A single beam of laser of 1927nm penetrates into the skin up to 50-90 microns (contingent upon pulse energy of 5-8mJ). Sequential radiation with a 1550nm beam followed by a 1927nm beam penetrates up to 300-350 microns. Sequential radiation of the skin with a 1927nm beam followed by a 1550 nm beam penetrates up to 300 microns. Simultaneous beam radiation with 1550nm together with 1927nm penetrates from 500 microns to 950 microns (almost 1 mm). Conclusion: The Authors conclude that the binary effect of simultaneous beam radiation of the tissue has a deeper penetration, and a more significant thermal effect in the skin than a single beam or sequential beam radiation.