Implantation Of NHA-PAH Keratoprostheses After Alkali Burns In Rabbit Eyes

Objective To explore biocompatibility and biohealing characteristics of the porous nanohydroxyapatite-polyvinyl alcohol hydrogel keratoprosthesis(NHA-PAH KPro) after that implanted into the diseased corneal stroma of rabbits,meanwhile,the study was to discuss the clinical feasibility of NHA-PAH KPro.Methods Ten New Zealand white rabbits were randomly numbered NO.1 to NO.10. The models of the alkali-burned corneas were randomly performed on rabbit eye. Stageâ… operation:The NHA-PAH KPro was inserted into the alkali-burned corneal lamella.The biocompatibility and corneal neovascularization were observed at scheduled times after operation.The operated eyes were then followed up for 3 months.Stageâ…¡operation:Removed the anterior lamellar cornea tissues,exposing the central optical core of the KPro.The stability of the KPro and complications were investigated by slit-lamp microscopy.Two of the animals were sacrificed at 1 month and 2 month after operation;the cornea were removed and examined by light microscopy;the surface of skirt was observed under scanning electron microscope. The remains of the rabbits were observed to describe clinical outcome,initially.Take the ultrasonic biomicroscope(UBM) exam to see the situation of anterior chamber angle.Results NO.7 rabbit was not implanted the KPro,because of trephination through the posterior corneal lamella during the operation,so the observation of NO.7 rabbit was ended.NO.7 rabbit had the KPro extrusion after 3 days of the implantation.The rest of NHA-PAH KPro had been retained during the experiment observation without severe complication such as infection,corneal melting,aqueous humor leakage and extrusion.The central optical core of the KPro kept transparence basically except for NO.8,NO.1 rabbit,without complications such as Kpro extrusion,aqueous humor leakage,retroprosthetic membrane,anterior synechia,posterior synechia or cataract. Both central and peripheral anterior chamber existed.Histological study:fibroblast and neovascularization had penetrated the microporous of the nanohydroxyapatite(NHA) skirt.The extracellular matrix deposited on surface of NHA skirt was more dense and tight.NO.8 and NO.1 rabbit had fiber proliferous membrane in front and post of the Kpro,respectively,occluding the pupil area. During the observation,the NHA-PAH KPro of NO.5,NO.9 had been retained for more than 7 month.Conclusions The skirt of NHA-PAH KPro can promoted the corneal neovaslarization and improve the interfacial biointegration of skirt and host cornea; The modified NHA-PAH KPros have obtained a relatively stable results after implantation into animal corneas;The micropores design of the NHA-PAH KPros profited the adhesion of the fibrocyte and promoted the corneal neovaslarization, because the former it can ameliorate the nutrition metabolizability theoretically;it has clinical feasibility for NHA-PAH KPro designed by ourselves.