两种软性聚甲基丙烯酸羟乙酯一体式人工角膜植入碱烧伤兔角膜的研究

The study of new soft one-piece PHEMA keratoprosthesis implanted into alkali burned rabbits cornea

目的 评估两种软性聚甲基丙烯酸羟乙酯（PHEMA）一体式人工角膜（Ⅰ型和Ⅱ型）植入碱烧伤角膜后的临床结果.方法 实验研究.将12枚两种人工角膜植入（各6枚）碱烧伤后的兔角膜,进行裂隙灯、眼底照相、B超及超声生物显微镜（UBM）检查.结果 所有植入物均稳定存留于角膜内,实验观察最长达72周.所有的人工角膜位置无移位,无结膜瓣裂开,无漏水,无感染,指测眼压正常,B超显示后节情况正常,UBM显示大部分动物出现虹膜粘连（10只眼）,眼底照相无视网膜脱离.Ⅰ型有3只眼发生后增殖物；Ⅱ型无后增殖物发生.每一例人工角膜表面可见增生的结膜覆盖光学区域.结论 新型的PHEMA一体式人工角膜没有界面问题,手术一次植入,其中Ⅰ型无需摘除晶体和玻璃体切除,Ⅱ型光学区后突出部分可能会降低后增殖膜的发生,并且采用的软性水凝胶材料使眼压测量成为可能,其长期效果需要进一步观察.

Objective This study was to evaluate clinical results of two types soft one-piece keratoprosthesis （KPros） made of PHEMA implanted to alkali burned rabbit corneas.Methods Experimental study.Twelve pieces KPros were implanted alkali burned rabbit corneas （type Ⅰ and Ⅱ,6 pieces respectively）.The examinations including slit-lamp,fundus photography,B-ultrasound and ultrasound biomicroscope （UBM）were carried out.Results All Kpros were stable and no complications happened including conjunctiva flap dehiscence,aqueous leak and infection.IOP were normal by finger touch.B-ultrasound show no retina detachment and UBM show synechia in most animals（10 case）.Retroprosthetic membrane happened in type Ⅰ （3 case）.Visible conjunctiva hyperplasia covering the optical region happened in all KPros.Conclusions （1） The same material,integrated design,maybe eliminating the material interface problem.（2） Simple surgical skills.（3） IOP measurement is possible because of soft material.（4） KPro I do not need removal of the lens and vitrectomy.The projecting portion of KPro Ⅱ may reduce the incidence of proliferative membrane.Long term effects need more cases and further observation.