800μm纤芯光纤发散角影响激光止血效果的离体作用研究

Changes of the divergence angle affect the hemostatic effect of 800 micron core fiber:An ex vivo study

目的在体外情况下,探究800μm纤芯光纤传输低功率绿激光在前列腺增生手术中远距离照射的止血范围。方法取新鲜猪肾脏,将组织固定于步进机下的实验操作台,分别设置光纤头距离肾脏组织1、2、3、4 cm,调试绿激光能量为10、20、30 W,分别照射肾脏组织5、10、15 s,观察其作用效果,使用游标卡尺测量激光投射光斑使肾脏组织产生凝固瘢痕的直径大小、凝固层厚度,并将照射后的组织制病理切片,在显微镜下观察其热损伤区域大小。结果随着光纤头距离肾脏组织越远、激光能量越大、照射时间越长,激光照射在肾脏组织的光斑越大,肾脏组织被凝固的范围更大、深度更深,汽化和碳化现象逐渐出现。在功率30 W、照射时间为10 s、照射距离为4 cm时,肾脏组织未出现汽化和碳化现象,但是凝固层约厚6 mm。结论本实验使用800μm光纤传输低功率绿激光能量,在远距离照射离体肾脏组织后组织产生了更大的凝固范围以及恒定的凝固层厚度,为临床激光远距离照射前列腺止血提供了一定的实验理论依据。

Objective To assess the far distance irradiation effects of low power of 532 nm laser transmitted by 800 μm core fiber in the surgery of benign prostatic hyperplasia(BPH) ex vivo.Methods Fresh porcine kidneys were irradiated with 800 μm core fiber with 532 nm wavelength,at 10 W,20 W and 30 W,respectively,for 5 s,10 s and 15 s at the distance of 1 cm,2 cm,3 cm and 4 cm.The size and thickness of scars caused by irradiation were measured with a vernier caliper.The irradiated tissues were sectioned to observe the thermal injury with a microscope.Results When the working distance was longer,the power of the laser increased;when the irradiation time was longer,the light spot was larger,the size of coagulation was larger and deeper,and carbonization and vaporization of the tissues could be observed.When the laser power was set at 30 W for 10 s at 4 cm,carbonization and vaporization of tissues were not observed.Conclusions The 800 μm core fiber used in our experiment caused large size of coagulation and stable depth of coagulation of renal tissues.This could provide certain reference for laser hemostasis in BPH surgery.The limitation of this experiment was that only one laser and fiber was used;therefore,we will try different kinds of lasers and fibers in future studies.