准分子激光原位角膜磨镶术后角膜瓣下上皮细胞植入伴瓣融解免疫组化及临床研究

目的 探讨准分子激光原位角膜磨镶术（excimer laser in situ keratomileusis,LASIK)后角膜瓣下上皮细胞植入伴瓣融解的免疫组化、临床特点及其处理方法。方法 对LASIK术后14例（15只眼）患者角膜瓣下上皮细胞植入的临床特点及处理方法进行分析,同时将其中部分瓣融解的4只眼角膜植入组织的刮除物,用4种单克隆抗体进行免疫组化和TUNEL法染色方法进行观察。结果 角膜瓣下上皮细胞植入后,角膜瓣最远端层间混浊,且逐渐扩大、浓密,角膜瓣缘缺损呈月食状,术后约3个月时病灶不再 扩大,刮除植入组织后角膜透明。植入组织HE染色、免疫组化染色及TUNEL法染色示：植入层内可见空泡样退行性变病灶,空泡内可见溶菌酶,植入层细胞具有自身凋亡的趋势,空泡内细已全部凋亡。结论 LASIK术后角膜瓣下的植入过程可分为上皮内生、角膜瓣部分消溶和自限3个时期。植入物的早期为有形膜状物质,晚期多为无结构物质,主要由细胞凋亡所致;角膜瓣的融解也可能是因细胞凋亡所致。对上皮植入葡匐性进展者,应尽早清除。

Immunohistochemical and clinical studies on sub-corneal flap epithelial implantation accompanied by flap melting after excimer laser in situ keratomileusis

Objective To study the immunohistochemical and clinical characteristics of the corneal epithelial cells implanted under the flap accompanied by the flap melting after excimer laser in situ keratomileusis (LASIK) and the method of management. Methods In eight eyes (In 4 eyes a part of the flap melted.) with corneal epithelial cells implanted under the flap after LASIK, the corneal flap was torn again. The implanted tissue was removed. After washing between the interfaces, the flap was repositioned. The implanted tissue was immunohistochemically stained by using four kinds of monoclonal antibodies and using terminal deoxyribonucleotide transferase mediated dUTP nick end labeling (TUNEL) method. Results Early in the course, the disorder appeared on the temporal side, expanded and thickened. The defective periphery of the corneal flap presented as a partial lunar eclipse. The melting process was self limited in 3 months. The result was good after the implanted tissue was removed. The implanted material was stained by using HE, immunohistochemical and TUNEL methods. Some vesicle like degeneration in the implanted layer was found. There was lysozyme in the vesicles, and the cells of implanted layer possessed a trend of apoptosis. All the cells were dead in the vesicles. Conclusions The progress of corneal epithelial implantation under corneal flap after LASIK may include 3 periods: epithelial implantation, corneal flap melting and self limitation. Early in the course, the implanted material presented as a thin film. Afterwards, it becomes a non structural material. Possibly the melting of the corneal flap is caused by apoptosis. Therefore, the implanted epithelium should be removed early.