The Study Of Corneal Wound Healing In Rabbits After Descemet's Stripping Endothelial Keratoplasty

INTRODUCTIONEndothelial dysfunction is one of the leading causes of corneal visual deficit.The only method of endothelial replacement for nearly 100 years has been full-thickness, penetrating keratoplasty(PKP)surgery.But there are many complications during and after the operation,which limit the final visual rehabilitation of the transplant patient. So corneal surgeons have been searching for a method of endothelial replacement that would be less invasive,safer,and more predictable than PKP.Great strides have been made in the endothelial keratoplasty surgery during the past ten years.Descemets stripping endothelium karatoplasty(DSEK),developed from the deep lamellar endothelial keratoplasty(DLEK)is more and more used for endothelial replacement, which leaves the corneal surface untouched,completely eliminates the use of corneal sutures,and avoids a lot of complications.So the patients can attain optimal vision quickly after the operation.Until now there have been only some literatures about the clinical observation after DSEK and the process of corneal wound healing and tissue repair is still unreported.The current study is designed to study the process of Corneal wound healing after DSEK,which will be helpful for wide clinical application.MATERIALS AND METHODSSixty rabbits were divided into the donor groups,DSEK groups and PKP groups, which consisted of 20 rabbits respectively.DSEK or PKP was performed in only one. eye of the rabbits.Observe the recovery of corneal transparency with slit lamp.Observe the adherence between the donor disc and recipient's bed and the change of corneal thickness with SL-OCT.Five rabbits were killed at 1 week,2 week,3 week and 4 week postoperatively,separately.The corneal buttons were harvested for histological study (HE staining).RESULTSClear cornea could be obtained in 19 recipient eyes after DSEK.The cornea of 1 recipient eye was opacity because of the dislocation of the donor disc.By slit-lamp examination,the corneal edema was serious at 3 day postoperatively and the cornea was completely clear at 4 week postoperatively.By SL-OCT examination,the donor disc and recipient's bed were adhered well,the cornea was obviously thicker than normal at 3 day postoperatively,then became thinner and thinner.4 weeks postoperatively,the corneal thickness restored to normal.By light microscope,the interface of the donor disc and recipient's bed was apparent in the early postoperative period.The slots between the collagen fibrils were wider than normal and the collagen fibrils did not arrange well.4 weeks postoperatively,the interface of the donor disc and recipient's bed was invisible and the collagen fibrils arranged in good order without scarring.Clear cornea could be obtained in 16 recipient eyes after PKP.The corneas of 4 recipient eyes were opacity because of the rejection of the donor grafts.There was no obvious increase of the corneal thickness postoperatively.4 weeks postoperatively,the arrangement of the collagen fibrils was not as normal as preoperatively and the corneal wound healing was still incomplete.CONCLUTIONThe corneal wound healing was rapid after DSEK without scarring in the central optical zone,which played an important part in the recovery of corneal transparency.