无防腐剂的1％利多卡因对年龄相关性白内障患者晶状体上皮细胞影响的病理学研究

Pathological study on effects of preservative.free 1% lidocaine on lens epithelial cells of patients with age-related cataract

目的探讨无防腐剂的1％利多卡因对年龄相关性白内障（ARC）患者晶状体上皮细胞（LEC）的作用及其作用机制。方法自身配对设计。收集75例（82只眼）ARC患者的晶状体前囊膜，其中男性40例（44只眼），女性35例（38只眼）；年龄41～85岁，平均67．97岁；皮质性自内障34只眼，核性22只眼，后囊膜下性26只眼。对超声乳化白内障吸除术中撕下的82只前囊膜标本分别用1％利多卡因溶液浸泡1min（利多卡因组）或用平衡液（BSS）浸泡1min（BSSⅠ、Ⅱ组）或不加入任何药物处理（对照组），然后行锥虫蓝-茜素红活性染色，显微镜照相，计数LEC及坏死细胞；并通过HE染色及电镜观察LEC的病理及超微结构改变。采用配对设计t检验和单因素方差分析对数据进行统计学分析。结果LEC坏死率对照组和BSSI组分别为（56．19±2．71）％和（57．23±1．98）％，两组间差异无统计学意义（t=2．0693，P=0．0505），利多卡因组和BSSⅡ组分别为（99．86±8．22）％和（57．64±7．00）％，二者比较差异有统计学意义（t=27．6781，P=0．0000），但利多卡因组内不同年龄组、不同性别、不同类型白内障患者LEC坏死率差异均无统计学意义（F值分别为0．03、2．37、0．71，P〉0．05）。HE染色显示利多卡因组LEC空泡变性明显，细胞与囊膜间出现空隙，胞核浓缩、碎裂、溶解。对照组和BSS组LEC结构基本正常，仍贴附于囊膜上。电镜下利多卡因组LEC形态不规则，细胞与细胞及细胞与囊膜间的连接崩解断裂，细胞膜内陷，细胞器严重变性，结构破坏，染色质凝聚、边集、裂解，不少细胞皱缩、脱落、消失。结论无防腐剂的1％利多卡因能松解ARC患者LEC间及细胞与囊膜间的连接，并可破坏细胞结构，导致细胞变性、坏死。

Objective To assess whether preservative-free 1% lidocaine is capable of destroying the LECs in age-related cataract （ARC） in order to provide scientific basis for pursuing safe and effective drugs to eliminate LECs in cataract surgery. Methods Lens anterior capsule （LAC） specimens were collected from 75 patients （ 82 eyes） with age-related cataract （ ARC）, including forty males （44 eyes） and thirty-five females （38 eyes）. The age range was 41-85 years, the mean age was 67.97 years. There were 34 cortical cataracts,22 nuclear cataracts and 26 subcapsular cataracts. Capsule specimens were divided into 4 groups： balanced salt solution （BSS） group Ⅰ and group Ⅱ （exposed to BSS for 1 minute） ,lidocaine group （exposed to preservative-free 1% lidocaine for 1 minute） and the control group. Specimens were stained with trypan blue and alizarin red. Photomicrographs of each capsule were taken to observe the viability of LECs and to count the number of necrosis LECs. The pathologic changes of LECs were evaluated by histological methods （11 LAC, 22 pieces） as well as transmission and scanning electron microscopes （5 LAC, 10 pieces）. In the control and BSS group Ⅰ （23 LAC） ,one half of each capsule specimen was used for the control group and the other half was used for BSS group Ⅰ. In lidocaine group and BSS group 11 （43 LAC）, one half of each capsule specimen was used for lidocaine group and the other half was used for BSS group Ⅱ. Results The rate of necrosis LECs of the anterior capsules in the control group and BSS group Ⅰ was （56. 19± 2. 71 ）% and （57. 23 ± 1.98 ）%, respectively. The rate of necrosis LECs of the capsules in lidocaine group and BSS group Ⅱ was （ 99. 86 ± 8. 22） % and （ 57. 64 ± 7.00） %, respectively. Matching t-test showed that the rate of necrosis LECs in lidocaine group was greater than that in the BSS group Ⅱ （ t = 27. 6781 ,P=0. 0000）. There was no significant difference in the number of necrosis LECs between the control group and BSS group I （t = 2. 0693,P = 0. 0505 ）. There was also no significant difference between males and females; between different cataract, types and between varying age groups （P 〉 0. 05 ）. After irrigated with lidoeaine,LECs showed vacuoles and detached from the capsule, and many cavities appeared between the LECs and the capsule. The capsules of BSS and control group showed a normal layer of LECs attached to the capsule. Under transmission and scanning electron microscopes, in lidocaine group, the junction between the LECs and between the cells and the capsule were destroyed; many cells detached from the capsule and the rest arranged loosely. Some LECs dented and many vacuoles emerged, resulting in destruction of the cellular structures. Conclusion Preservative-free 1% lidocaine may loose the junction between LECs and between the cells and the capsule, and also destroy cellular structures, resulting in degeneration and necrosis of the LECs.