不同材料人工晶状体表面表皮葡萄球菌黏附实验的研究

摘要

Background Postoperative endophthalmitis following intraocular lens(IOL)implantation is still one of the most feared complications of cataract surgery.Bacterial adhesion to IOLs during their insertion is a prominent etiological factor.The adhesion characteristics of bacteria to IOL are very vital for the prevention of endophthalmitis after cataract surgery.Objective The present study was to observe the in vitro adherence ability of Staphylococcus epidermidis to different intraocular lenses(IOLs)and compare the results in bacterial counting between scanning electron microscopy(SEM)photographs and quantitative cultures. Methods Five types of IOLs,including hydrophobic acrylic IOL,polymethylmethaerylate(PMMA)IOL,heparin-surface-modified(HSM) PMMA IOL,silicone(SI)IOL and hydrophilic acrylic IOL,were put into S.epidermidis(ATCC 12228)suspension for 1 hour.The bacterial adhesion numbers on the IOL surfaces were counted by quantitative cultures and scanning electron microscopy(SEM) photographs. Results Quantitative culture counting of viable adherent bacteria released by sonication showed that hydrophobic acrylic IOL and PMMA IOL were more likely for bacteria to attach.The number of bacteria on the five types of IOL surfaces showed significant differences(F=100.084,P=0.000).No significant differences were found in the number of bacteria between hydrophilic acrylic IOL and HSM-PMMA IOL (t=2.285,P=0.052)with the quantitative culture method.Direct counting of adherent bacteria in SEM photographs revealed that there were significant differences in bacterial adhesion numbers among difierent IOL material groups,with the numbers from high to low as follows:Hydrophobic IOL＞PMMA IOL＞SI IOL＞Hydrophilic IOL＞HSM-PMMA IOL(F=118.065,P=0.000).The counting method by SEM method was superior to that by quantitative cultures (t=5.019,P=0.000). Conclusion The bacterial adhesion ability varies upon the difference of IOL materials.Less bacterial adhesion is found on hydrophilic acrylic IOL and HSM-PMMA IOL,implying that the use of IOLs made from these two materials during surgery could diminish the incidence of postoperative endophthalmitis and intraocular inflammation associated with IOLs implantation.%背景感染性眼内炎是白内障摘出及人工晶状体(IOL)植入术后最严重的并发症之一,细菌黏附于IOL表面随手术带入眼内是其主要原因,了解细菌对IOL的黏附情况对预防术后眼内炎的发生具有重要意义.目的研究不同材料的IOL光学表面表皮葡萄球菌的黏附情况,比较细菌培养菌落计数及扫描电子显微镜计数2种方法的优缺点.方法疏水性丙烯酸酯IOL、聚甲基丙烯酸甲酯IOL(PMMA IOL)、肝素修饰聚甲基丙烯酸甲酯(HSM-PMMA IOL)、硅凝胶IOL(SI IOL)、亲水性丙烯酸酯IOL 5种不同材料的IOL(每种6枚)置于表皮葡萄球菌(ATCC12228)细菌悬液1h后,采用细菌培养菌落计数及扫描电子显微镜2种方法观察表皮葡萄球菌在各种IOL表面的黏附数量.结果细菌培养菌落计数发现疏水性丙烯酸酯IOL和PMMA IOL最易于黏附细菌,亲水性丙烯酸酯和HSM-PMMA IOL黏附的细菌最少,5种IOL中细菌黏附数的比较差异有统计学意义(F=100.084,P=0.000),亲水性丙烯酸组和HSM-PMMA组间差异无统计学意义(t=2.285,P=0.052);扫描电子显微镜观察结果显示5种IOL组细菌在IOL上光学分布表面计数的总体比较差异有统计学意义,按照细菌在IOL上黏附的数量从多到少依次为Hydrophobic>PMMA>SI>Hydrophilic＞HSM-PMMA(F=118.065,P=0.000).两种细菌菌落计数方法比较发现扫描电子显微镜法优于细菌培养菌落计数法,差异有统计学意义(t=5.019,P=0.000).结论 5种IOL中以亲水性丙烯酸酯和HSM-PMMA IOL 黏附的细菌最少,提示亲水性丙烯酸酯IOL和HSM-PMMA IOL在降低白内障IOL植入术后眼内炎的发生方面有一定的作用.