corneal transplant

Corneal transplantation is the replacement of a opaque or diseased cornea with a transparent cornea to achieve visualization, treatment of certain corneal diseases, and improved appearance. It is the best surgery for allografts. Indication 1. Corneal degeneration or malnutrition. 2, corneal leukoplakia caused by various reasons. 3, infection (virus, bacteria, fungi, amoeba) caused by drugs can not control keratitis or ulcers. 4, opacity after corneal stroma, congenital corneal opacity. 5, keratoconus (denaturation period). 6, corneal blood staining. 7, severe corneal trauma, laceration, chemical injury. 8, after the elastic layer bulging, corneal sputum. 9, corneal endothelial function decompensation, corneal bullous lesions. Preoperative preparation 1. The patient has 0.3% norfloxacin eye drops 1 to 2 days before surgery. 2, preoperative night 0.25% ezrin eye ointment, or 1% pilocarpine eye drops 2 times before surgery. 3, infectious keratopathy as a pathogen test (smear test bacteria + culture). 4, chemical burns to check tear film rupture time and tear secretion test. 5, through the injury to do b super or x-ray film. 6, 1 hour before surgery, vaginal azide 0.5g and diazepam 5mg, pediatric 20% mannitol (4ml / kg) intravenous infusion. 7, anesthesia: adult ball, orbicularis muscle. Pediatric basic anesthesia plus local anesthesia, oppression of the eye for 10 minutes. Surgical procedure 1. The suture or the opener is opened. The upper and lower rectus muscles are fixed with sutures. Corneal fistula, perforation, aphakic eyes and pediatric patients suture fleiringa rings. 2, according to the range of corneal lesions to choose the trephine, generally with 7 ~ 7.5mm ring drill to drill the plant bed. Adults generally choose a 0.25mm trephine drill than the graft, drill the implant bed and cut the diseased cornea. 3. Drilling the transplanted piece: 1 From the epithelial surface, the left hand is covered with gauze wrapped around the cornea, and the right hand-held trephine is placed vertically in the center of the donor cornea. After drilling through, the corneal graft is cut with a cornea. 2 From the endothelium, the corneal flap with the scleral flap should be removed. 3 Place the corneal endothelium face up on the cutting pillow and cut the corneal graft with a sharp lap. 4. Fix the graft and place the graft on the graft hole. The 10-0 nylon suture is fixed at 12, 6, 3, and 9 points. Intermittent suture, generally 16 needles, continuous suture 22 ~ 24 needles, intermittent sutures easy to adjust sutures to reduce astigmatism after surgery, continuous suture stimulation, strict wound closure, reducing operation time. Stitching should reach 4/5 of the corneal thickness. 5. Reconstruction of the anterior chamber: Inject physiological saline or disinfectant air from the edge of the graft to reduce the anterior iris adhesion and the turbidity of the graft to achieve watertightness. 6, astigmatism examination, using a corneal scattered disc under the microscope to adjust the tightness of the suture. 7, surgery under the conjunctiva injection of gentamicin 20,000 units, dexamethasone 2.5mg, including both eyes.