硅油眼并发性白内障晶状体上皮细胞超微结构观察

Ultrastructural changes of lens epithelial cells in cataract following silicone oil infusion

目的白内障是眼内硅油填充术后最常见的并发症,其具体的发病机制目前尚未完全明确。应用扫描电子显微镜及透射电子显微镜对硅油眼并发性白内障晶状体前囊膜及上皮细胞的超微结构进行观察分析,为其发病机制及病理改变的研究提供新的线索及依据。观察硅油填充眼并发性白内障晶状体前囊膜及晶状体上皮细胞(lens epithelial cells,LECs)的超微结构改变,探讨硅油在并发性白内障的发生、发展中的作用。方法选取我科2006年5月至2007年10月行硅油取出术患者12例(12只眼),行白内障囊外(ECCE)或超声乳化(Phaco)联合硅油取出术,术中取晶状体前囊膜,浸入3%戊二醛固定液中固定后制作病理标本,分别在扫描电子显微镜(SEM)、透射电子显微镜(TEM)下观察其超微结构改变。结果硅油眼并发性白内障在SEM下可观察到可见部分上皮细胞及ECM脱离前囊膜,晶状体前囊膜LECs游离面呈舌状或瓦片状,覆盖于相邻细胞顶部,并大片状缺失或脱离前囊膜。上皮细胞呈扁平立方形,细胞核呈圆形或椭圆形。TEM下观察晶状体前囊膜为均质的基底膜,前囊下LECs形态极不规则,呈长梭形或扁平状,相邻细胞结合也较疏松,可见大量大小不等空泡存在。LECs间以指状突紧密镶嵌或缝隙连接,线粒体肿胀,嵴消失。细胞核呈椭圆形,密度加深,核内染色质浓缩、边集、固缩呈典型的细胞凋亡表现。结论硅油可促进并发性白内障的发生、发展,硅油眼并发性白内障最终以LECs细胞凋亡为主要形式。

Objective To observe the ultrastructural changes of lens epithelial cells of complicated cataract after silicone oil infusion,and to evaluate the effect of silicone oil on initiation and development of cataract after silicone oil infusion.Methods Twelve patients（12 eyes） who underwent silicone oil removal in our department during the period from May 2006 to October 2007 were recruited randomly into this study.Patients received either extracapsular cataract extraction or phacoemulsification.Anterior capsules were sampled and stained with 3% glutaraldehyde fixation,and observed under scanning electron microscope（SEM） and transmission electron microscope（TEM）.Results Observations with SEM： some endothelial cells or ECM were detached from anterior capsule anterior capsule.The lingulate or tile shaped exposed side of LECs were covering neighboring epithelial cells.Cells were flat and cubic with round or oval nuclei.Observations with TEM： anterior capsules were composed of homogeneous basement membranes.Shape of LECs was extremely irregular,with spindle or flat appearances.Cell conjugations were loose and there were multiple vacuoles of various sizes intracellularly.LECs were connected tightly with gapjunctions.Swollen mitochondriaand flattened crests were also observed.Nuclei were elliptical and highly dense.Typical features of apaptosis,such as chromoplasm condensation,margination,and shrinkage were presented.Conclusion Silicone oil facilitates the initiation and development of cataract,in which apoptosis of LECs plays an important role.