Purpose To investigate the surgical procedure,and to evaluate the clinical efficacy,complications and histological changes after descemet membrane endothelial keratoplasty(DMEK).
Methods It was an experimental study. Donor grafts were dissected from 10 New Zealand rabbit eyes.Another 20 New Zealand rabbits were divided into two groups randomly, 10 rabbits per group.DMEK was performed in the right eyes,and the left eyes were used as normal controls.Group A was experimental group:a 3mm limbal incision was made.Descemet membrane and endothelium were stripped off at a 8.5 mm diameter,then the same size of graft made by air-bubble method only including descemet membrane and endothelium was inserted into recipient,s anterior chamber. Sterile air was injected to strengthen the attachment.Group B was experiment control group:the procedure was similar to group A,but without any graft transplanted. The corneal transparency, graft placement and anterior chamber were observed
under slit lamp.The attachment of graft and the change of corneal thickness were evaluated by SL-OCT. Tissue slicing and HE staining were made to observe the histological changes.
Result In group A,there were 6 corneas resumed transparent in 7 days. The grafts were adhered well under the SL-OCT .The margin of two grafts were curled. They recovered again after re-bubbling.But there were also 2 grafts were failed because of serious dislocation. The cornea was
obiouslv thicker at 3 day postoperatively,and then gradually became thinner,and 1-2 weeks later,corneal thickness restored to normal. The corneas were severe edema after surgery in group B with neovascularization whose cornea is much thicker than group A at any time.Under the light microscope,the interface of the donor disc and recipient’s bed was apparent in the early period of postoperation.Four weeks later,the interface was invisible without scarring.
Conclusion DMEK is a new form of endothelium keratoplasty.The graft of DMEK is get closer to normal corneal structure.So it may become the first choice for the treatment of bullous keratopathy. |