1.When is corneal transplantation feasible in patients with chemical injuries? Patients with chemical injuries to the eye surface are generally not eligible for corneal transplantation in the early stage, unless corneal autolysis or perforation occurs. After the condition has stabilized for six months, we will decide whether corneal transplantation can be performed according to the condition. However, since there is often a large number of new blood vessels growing into the cornea at this time, the chances of rejection after surgery are greatly increased. 2.What is corneal transplantation? Corneal transplantation is the use of allogeneic normal transparent corneal tissue to replace the cloudy, diseased corneal tissue to restore sight or control corneal disease in the affected eye, which is one of the important sight restoration surgeries in ophthalmology. 3.What is lamellar keratoplasty? Laminar keratoplasty is a partial thickness corneal transplant. Only the diseased tissue in front of the cornea is removed during surgery, and then a partial-thickness clear corneal donor is transplanted to repair the excised area. The chance of postoperative immune rejection is low. It is commonly used in the treatment of superficial corneal opacities, corneal dystrophy opacities, cone corneas, superficial corneal infections, corneal tumors, etc. 4.What is penetrating keratoplasty? Penetrating keratoplasty is a method of replacing a full layer of cloudy and diseased cornea with a full layer of clear cornea. The indications can be divided into optical, therapeutic, shaping and cosmetic according to their surgical purpose. The common indications for optical corneal transplantation are conical cornea, corneal scarring due to various causes, various corneal dystrophies, and corneal endothelial cell failure due to various causes. The main indications for therapeutic corneal transplantation are infectious corneal disease and chemical injuries to the eye. Penetrating corneal transplantation carries the risk of immune rejection. 5.What is artificial cornea transplantation? Artificial keratoplasty is a surgical procedure in which a special optical device made of transparent medical polymer material is surgically implanted into the corneal tissue to replace part of the corneal scar tissue and restore vision. Since the problems such as rejection of synthetic materials by corneal tissues have not been finally solved, the long-term effect is not good, often causing atrial water leakage at the transplantation site and the detachment of the transplantation piece, so it is not possible to be widely used yet. At this stage, artificial cornea is only suitable for those who suffer from double vision after various serious corneal diseases, especially severe chemical burns caused by all corneal leukoplakia and repeated corneal transplantation failure, unable to do other surgeries. 6.Will immune rejection occur after corneal transplantation? Because normal corneal tissue has no blood vessels, it is “immune relative immune immunity”, so corneal transplantation is the most successful type of organ transplantation at present. The incidence of immune rejection in normal corneal transplants is less than 10%, while the incidence of immune rejection in high-risk corneal transplants is greater than 60%. High-risk corneal transplantation includes types of corneal transplantation such as corneal vascularization, large graft pieces or near the corneal edge. 7.What are the symptoms of rejection after corneal transplantation and how to treat them? Post-transplant rejection can occur at any stage, with the peak period being 3-6 months after surgery. The main symptoms are eye redness, vision loss, photophobia and tearing. If any of these symptoms occur, do not be alarmed and go to the hospital immediately. If treated promptly, most immune rejection can be controlled by medication.