脉冲1.338μm激光角膜损伤效应研究  

Corneal Injury Induced by Pulsed 1.338 μm Laser Radiation

作　　者：杨在富[1] 王嘉睿[1] 陈虹霞[2] 景小敏[1] 杨景庚[1] 张笑明[1] 

机构地区：[1]军事医学科学院放射与辐射医学研究所,北京100850 [2]中国人民解放军总医院第一附属医院皮肤科,北京100048

出　　处：《激光生物学报》2012年第6期497-501,共5页Acta Laser Biology Sinica

基　　金：国家科技重大专项(2008ZXJ09014093);国家自然科学基金(30600493;61275194)资助

摘　　要：目的:实验研究脉冲1.338μm激光的角膜损伤效应,确定其损伤阈值,并与10.6μm激光角膜损伤特点进行比较。方法:采用输出波长1.338μm、脉冲宽度5 ms的Nd:YAG激光为照射光源,角膜光斑直径1.7 mm,以不同剂量的激光照射新西兰白兔角膜,于照后1 h观察角膜损伤情况,统计损伤发生率,采用加权概率单位法计算损伤发生率为50%时所对应的激光剂量,即损伤阈值ED50。在1.5倍阈值剂量下比较该激光与10.6μm激光角膜损伤的特点。实验中注意观察晶状体和眼底是否有损伤。结果:脉冲1.338μm激光角膜损伤阈值为27.0 J/cm2(95%置信区间25.8～28.1 J/cm2)。阈值水平下,角膜损伤斑肉眼观察呈淡淡的灰白色,裂隙灯下可见一与角膜同厚的灰白色反光带,晶状体或视网膜正常;1.5倍阈值剂量下,角膜损伤斑为清晰的瓷白色,裂隙灯下可见一与角膜同厚的白色反光带,同时观察到晶状体前表面白色反光点,但视网膜无变化。与之相比,10.6μm激光角膜损伤在裂隙灯下仅观察到一很窄的亮白反光条,位于角膜表层。结论:脉冲1.338μm激光在光斑直径1.7 mm,脉冲宽度5 ms条件下的角膜损伤阈值为27.0 J/cm2。角膜损伤特点是,损伤斑呈灰白色或瓷白色,累及角膜全层,而10.6μm激光损伤仅累及角膜浅层。Objective： To establish the corneal damage threshold （ EDso ） for 1. 338 μm laser exposure and compare the corneal damage effects between 1. 338 μm and 10.6 μm laser radiation. Methods： A neodymium： Yttrium alumi- num gartnet （Nd：YAG） laser was used to deliver 1. 338 μm laser to the cornea of New Zealand rabbit. The laser spot diameter on cornea was limited to 1.7 mm. The pulse duration was 5ms. The exposed sites were elinieally evaluated for presence of lesions at 1 h post-exposure. The EDso was calculated with probit analysis method. Under the laser dose of 1.5 times of threshold,the corneal damage effects induced by 1. 338 μm and 10.6 μm laser radiation was compared. Results：The rabbit corneal EDso for 1. 338μm laser exposure was determined to be 27.0 J/cm^2 ,with the 95% confi- dence interval of 25.8 - 28.1 J/cm^2. Corneal damage induced by threshold exposure was a faint white-grey spot and the whole thickness of cornea involved. When the laser dose was increased to 1.5 times of threshold, the cornea showed a distinct white spot and the lens was also injured. As comparison, only the superficial layer of cornea was damaged whenthe laser changed to 10.6 μm. Conclusion ： The established EDso of rabbit cornea for pulsed 1. 338 μm is 27.0 J/cm^2. The corneal lesion induced by 1. 338 μm laser showed a characteristic full thickness lesion, while that induced by 10.6 μm laser showed only superficial lesion.

关 键 词：脉冲1.338μm激光 角膜 损伤效应 损伤阈值 

分 类 号：R136.2[医药卫生—劳动卫生] R779.12[医药卫生—公共卫生与预防医学]