Nd∶YAP激光照射活体大鼠肝脏生物效应的实验研究

Biological Effects of Nd∶YAP Laser Irradiation on Liver in vivo Rats:an Experimental Study

目的探讨Nd∶YAP激光不同方式照射活体大鼠肝脏对组织的不同影响。方法大鼠15只,按照射方式分为非接触式、接触式、插入式3大组,每组5只鼠。每组分别以功率为3.0、3.5、4.0、4.5和5.0W,照射时间4s,光斑直径为0.5mm的Nd∶YAP激光照射大鼠中叶、右侧叶肝脏。每脏叶照射3～6点,点间间隔>0.5cm。照射后肉眼观察肝脏变化,并于照射处取材,常规石蜡切片,HE染色,光镜下观察。结果各组以功率3.0～3.5W的Nd∶YAP激光照射,以凝固性变化为主,随着功率增加除凝固效应外还逐渐表现出气化效应,组织穿透深度也由约0.5mm逐渐增加至约2.5mm。与相同功率和作用时间非接触式照射比较,接触式照射和插入式照射组织出现更多的缺损和更深的穿透深度。非接触式照射功率较高时出现组织爆破现象,接触式照射和插入式照射组织反应均平稳,无爆破现象,插入式照射较易伤及周围肝脏组织。结论非接触式照射、接触式照射和插入式照射是Nd∶YAP激光照射肿物的可行性方法,可根据肿瘤组织厚度适当选择非接触式照射、接触式照射和插入式照射方式进行照射治疗,但应正确掌握照射功率避免引起照射处周围组织的损伤。

Objective To explore the influence of different irradiation methods on hver in vivo rats by Nd ： YAP laser. Methods Fifteen rats were divided into three groups according to the operation methods, there were no-contact, contact and insertion irradiation groups, respectively, five rats in each group. Nd ： YAP laser was used to irradiate liver middle and right lobes with light spot of 0. 5 mm diameter, and the irradiation power was 3. 0, 3.5, 4. 0, 4. 5 and 5.0 W, respectively, in varous groups, the working time was 4 s. Every hepatic lobe was irrdiated with 3 to 6 light spots with interval above 0. 5 cm. After that the morphology and pathological changes of cases under light microscope were observed. Results The tissues were mainly coagulated in 3.0-3.5 W by all three methods. As increasing in power it aslo demonstrated the gasification, and the penetrating depth was gradually increased from about 0. 5 mm to 2.5 mm. Compared with non-contact irradiation, tissues with contact irradiation and insertion irradiation had more damaged and deeper penetration depth at the same power and action time. The tissues blasted when exposure at a higher power with non-contact irradiation while the rest were stable in the used power dose of the experiment. The insertion irradiation seemed easy to damage tissues around. Conclusions Nd ： YAP laser is a feasible method to treat tumors which can choose non-contact irradiation, contact irradiation or inser- tion irradiation with the power of 3.0-4. 5, 3-5, and 3-4 W, respectively, according to the thickness of tissues, but the operator should know well the power action thus avoiding damage to the surrounding tissues.