Transplantation of the cornea (corneal transplantation, through keratoplasty) is performed in order to:
- improve the optical properties of the cornea and eyesight, for example replacing the cornea that has healed after the corneal ulcer; clouded (Fuchs's dystrophy or swelling after cataract surgery); with a turbid cornea in connection with the deposition of opaque abnormal stromal proteins (eg, in hereditary stromal dystrophy of the cornea); with incorrect astigmatism, with keratoconus;
- restore the anatomical structure of the cornea to preserve the eye, for example, in the perforation of the cornea;
- treatment of a disease resistant to therapy, for example, with a severe fungal ulcer of the cornea; or to relieve pain, for example, when feeling foreign body due to recurrent rupture of blisters in bullous keratopathy.
The most frequent indications for corneal transplantation are bullous keratopathy (artifacial, endothelial dystrophy of Fuchs, aphakic), keratoconus, repeated transplantation of tissues, keratitis (viral, bacterial, fungal, Acanthamoeba, perforation) and corneal stromal dystrophy.
Usually, tissue selection is not performed. Cadaver tissue that is suspected of having an infection should not be used.
Transplantation of the cornea can be performed using general anesthesia or local anesthesia with intravenous administration of sedatives.
Local antibiotics are used after the operation for several weeks, and local glucocorticoids - for several months. In order to protect the eye from accidental trauma after transplantation, the patient wears a bandage, glasses and sunglasses. In some patients, in the early postoperative period, corneal astigmatism can be reduced by adjusting the seam or partially removing the suture. Achieving maximum visual acuity can take up to 18 months due to a change in refraction after removal of the suture, wound healing and / or correction of corneal astigmatism. In many patients, earlier and better vision is achieved by wearing rigid contact lenses over the corneal transplant.
Complications include infection (intraocular or corneal), wound filtration, glaucoma, transplant rejection, transplant failure, high refractive error (astigmatism and / or myopia), and relapse (eg, herpes simplex, hereditary stromal dystrophy of the cornea).
68% of transplant rejections are reported. The patients develop a decreased vision, photophobia, pain in the eye and redness of the eye. Transplant rejection is treated locally with glucocorticoids (eg, 1% prednisolone hourly), sometimes with an additional periocular injection (eg, 40 mg methylprednisolone). If transplant rejection is severe, glucocorticoids are additionally administered orally (eg, prednisolone 1 mg / kg 1 time per day) and sometimes intravenously (eg, methylprednisolone 3-5 mg / kg 1 time per day). Usually the episode of rejection is reversible and the function of the transplant is completely restored. A transplant can become nonfunctional if the episode of rejection is severe or long-lasting, and after many episodes of transplant rejection. A repeat transplant is possible, but the long-term prognosis is worse than at the first transplant.
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