Laser biological effects are a hot topic in laser medicine. In this study, to explore the quantitative biological effect of laser-induced wound healing and to provide guidance for expanding the clinical application of laser therapy, the injury effects and repair characteristics of skin tissue are studied through infrared laser irradiation of the skin of miniature pigs. Live pig skin was irradiated at multiple spots one time by using a grid-array method with a 1064 nm laser at different power outputs. The skin injury reaction was observed immediately after laser irradiation from low to high doses. The incidence of skin injury was calculated quantitatively. The healing and pathological changes after laser-induced skin injury were observed dynamically within 6 h and for 28 d after laser irradiation. With the increase of irradiation dose, laser-induced skin injuries ranging from mild to severe appeared in turn. The damage threshold of laser irradiation ED 50 is 47.4 J cm −2 with the laser; from 3 d to 28 d after irradiation, the pathological results showed that wound healing tended to be different in all groups, but this trend weakened with the increase in laser irradiation intensity. With the increased irradiation dose, skin injury appears as different types of injury plaques, ranging from mild to severe. Skin injury is worsened and the tissue repair trend is weakened with the increase in laser irradiation dose, producing a good dose-effect and time-effect relationship.

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Background: Laser eye dazzling affects the visual performance through the instant high-intensity light stimulation. The temporary loss or deterioration of the visual function may occur when radiated by lasers. To quantitatively evaluate the dazzling effect of each spectrum band of supercontinuum laser, we conducted an experimental research for exploring the safety and dazzling of animals’ eyes. Methods: Under the condition of dark adaption, the laser with different power densities and spectral bands was output, and the rabbit eyes were radiated by normal incident mode for 0.25 s. The fundus of the rabbit eyes was examined through the inspection mirror, and the upper limit of safe power density was explored. Rabbit eyes were radiated at the upper limit of safe power density, and the microscopic damage model was established for pathomorphological analysis. The eyes were radiated with blinding light for 0.1 s. The visual electrophysiological signals were collected dynamically and the recovery time of ERG-b amplitude was recorded and analyzed after laser radiation. Results: Under dark adaptation, the upper limit of safe power density was 247.00 mW/cm2 in the VS, 194.00 mW/cm2 in the VIS, 1184.00 mW/cm2 in the IS, and 1052.00 mW/cm2 in the FS. The above power densities of laser radiation in rabbit eyes could cause pathological changes of retinal structure, such as local bulge, uneven thickness and disorder of inner and outer nuclear layers, local inflammatory exudation and so on. When the power density was 8.00 mW/cm2, the recovery time of ERG-b wave in rabbit eye was 4.11 ± 0.67 s. When the power density was 12.00 mW/cm2, the recovery time of ERG-b wave in rabbit eye was 4.16 ± 0.55 s. The recovery time of ERG-b wave was 4.50 ± 0.94 s at the power density of 4.60 mW/cm2 in the full spectrum-1, 3.81 ± 0.11 s at the power density of 5.00 mW/cm2 in the full spectrum-2, and 628.00 mW/cm2 in the infrared spectrum. The recovery time of ERG-b wave was only 0.84 ± 0.09 s. Conclusion: The VS, FS, FS-1 and FS-2 of the supercontinuum laser had a good dazzling effect on rabbit eyes, and the dazzling effect was enhanced with the increase of radiation power density, but the infrared spectrum had a little dazzling effect.

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