Effects of 1 470 nm Semiconductor Laser on Vaporization Ablation, Cutting, and Coagulation in Ex Vivo Animal Tissue / 实验动物与比较医学

ABSTRACT

Objective To observe the effects of a 1 470 nm semiconductor laser on vaporization cutting, coagulation, and thermal injury of ex vivo animal tissues, aiming to explore the feasibility of its application in the treatment of benign prostatic hyperplasia.Methods The experimental group and control group were treated with HANS-D1 and ML-DD01FI 1 470 nm semiconductor laser therapy equipment, respectively. Fresh ex vivo pig bladder tissue was exposed to lasers with the optical fiber placed at distances of 0.5 cm and 1 cm from the tissue for 5 s. The effects of layers at powers of 60, 90, 120, 150, and 160 W on tissue injury were observed. Ex vivo dog prostate and pig kidney tissues were used for vaporization ablation and cutting to observe the effects of lasers at the same power levels on tissue vaporization and cutting thermal injury. Additionally, in coagulation mode, the effects of 30, 40, and 50 W semiconductor lasers on tissue coagulation were observed after irradiating ex vivo pig kidney tissue for 5, 10, and 15 seconds. Results When the optical fiber was placed 1 cm away from the tissue, the 1 470 nm semiconductor lasers did not cause accidental damage to adjacent normal bladder tissue. However, at a distance of 0.5 cm, the 120 W, 150 W, or 160 W lasers caused slight damage to the bladder tissue. In addition, with the increase in output power, the vaporization ablation efficiency of 60-160 W lasers on dog prostate tissue gradually increased, showing a good linear correlation between vaporization volume and total energy consumption (P<0.001). Histopathological HE staining results indicated that the coagulation layer thickness in the experimental group was 292.20-309.98 µm, and the vaporization layer depth was 1.49-4.52 mm. In the control group, the coagulation layer thickness was 289.91-303.53 µm, and the vaporization layer depth was 1.88-4.43 mm. There was no significant difference between the two groups (P>0.05). Moreover, when performing vaporization cutting on ex vivo pig kidney tissue with a cross-sectional area of 1 cm2, the efficiency of vaporization cutting by the 60-160 W 1 470 nm semiconductor lasers increased with the increase in output power (P<0.05). The coagulated layer thickness in the experimental group was 496.04-514.47 µm, while that in the control group was 489.39-518.53 µm. Additionally, in coagulation mode, when ex vivo pig kidney tissue was irradiated for 5, 10, and 15 s with 30, 40, and 50 W semiconductor lasers, the coagulation diameter, groove depth, and coagulation efficiency gradually increased with the increase in laser output power (P<0.05). The coagulation layer thickness in the experimental group and control group was 399.10-449.98 µm and 392.97-447.65 µm, respectively, and the vaporization layer depth was 3.05-7.09 mm and 2.70-7.14 mm, respectively. There was no significant difference between the two groups (P>0.05).Conclusion The 1 470 nm semiconductor laser shows good vaporization ablation, cutting, and coagulation effect on ex vivo tissues, with a good linear correlation between the effect and the output energy.