用于大功率激光治疗的瞬态喷雾冷却系统

Transient spray cooling system for high-power laser treatment

大功率激光治疗过程中,避免表皮及正常组织的热损伤副作用,是保证激光治疗安全性和有效性的关键。本文采用具有高制冷性能的医用134a制冷剂,通过对高压储液罐、密闭传输管路、高速雾化喷射装置以及电子学控制等系统的设计,形成了可与治疗激光不同时序输出、对皮肤和组织进行实时快速冷却的瞬态喷雾冷却系统。通过研究喷洒时间、喷射距离、类皮肤材料温度变化之间的量效关系,验证了装置的冷却效果。实验结果表明,在20~50ms喷洒时间内可将组织温度降低40~60℃。冷却系统的生物兼容性、耐压性、密封性通过了医疗器械注册检验。并联合大功率1450nm半导体激光用于面部痤疮的临床治疗,189例轻中度痤疮患者在连续治疗4次后治疗的总有效率达87.3%,未出现皮肤热损伤。该瞬态喷雾冷却系统可与各类激光治疗设备集成应用,提高了现有激光治疗技术的安全性、有效性和治疗范围。

During high-power laser treatment,protection of the epidermis and normal tissues from thermal damage is critical to ensure safety and effectiveness of the process. In this investigation,medical134a cryogen with high cooling performance was used,and a high-pressure storage tank,an airtight transmission line,a high-speed atomized spray device,and an electronic control system were designed as part of a transient spray cooling system combined with laser therapy for different output timings to cool the skin and tissue in real-time. By studying the relationship between the spraying time,jet distance,and temperature changes of materials that are similar to skin,the cooling effect of the device was evaluated. The experimental results show that the tissue temperature can be reduced from 40 ℃ to 60 ℃ in 20 ms to 50 ms. The biological compatibility,pressure resistance,and sealing of the cooling system met the requirements of medical device registration. The system was combined with a high-power1 450 nm semiconductor laser to treat facial acne in a clinical setting,and the total effective rate for189 patients with mild-to-moderate acne is 87.3% after four treatments without thermal damage. It is possible to combine the transient spray cooling system with various laser devices to improve the safety,effectiveness,and scope of existing laser treatments.