All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Corneal transplantation: procedure, prognosis
Medical expert of the article
Last reviewed: 04.07.2025
Corneal transplantation (corneal transplantation; penetrating keratoplasty) is performed for the purpose of:
- improve the optical properties of the cornea and vision, for example by replacing a cornea that has healed after a corneal ulcer; become cloudy (Fuchs' dystrophy or edema after cataract surgery); with a cloudy cornea due to deposits of opaque abnormal stromal proteins (for example, in hereditary corneal stromal dystrophy); with irregular astigmatism, with keratoconus;
- restore the anatomical structure of the cornea to preserve the eye, for example, in case of corneal perforation;
- treatment of disease that is resistant to therapy, such as severe fungal corneal ulcer; or to relieve pain, such as foreign body sensation due to recurrent rupture of blisters in bullous keratopathy.
The most common indications for corneal transplantation are bullous keratopathy (pseudophakic, Fuchs endothelial dystrophy, aphakic), keratoconus, re-tissue transplantation, keratitis (viral, bacterial, fungal, Acanthamoeba, perforation) and stromal corneal dystrophies.
Tissue matching is not usually performed. Cadaveric tissue suspected of being infected should not be used.
Corneal transplantation can be performed using general anesthesia or local anesthesia with intravenous sedation.
Topical antibiotics are used for several weeks postoperatively, and topical glucocorticoids are used for several months. To protect the eye from inadvertent trauma after the transplant, the patient wears a patch, glasses, and sunglasses. In some patients, corneal astigmatism can be reduced early postoperatively by suture adjustment or partial suture removal. It may take up to 18 months for peak visual acuity to be achieved due to changes in refraction after suture removal, wound healing, and/or correction of corneal astigmatism. Many patients achieve earlier and better vision by wearing rigid contact lenses over the corneal transplant.
Complications include infection (intraocular or corneal), wound leakage, glaucoma, graft rejection, graft failure, high refractive error (astigmatism and/or myopia), and disease recurrence (eg, herpes simplex, hereditary corneal stromal dystrophy).
Graft rejection is reported in 68% of cases. Patients develop decreased vision, photophobia, ocular pain, and ocular redness. Graft rejection is treated with topical glucocorticoids (eg, 1% prednisolone hourly), sometimes with an additional periocular injection (eg, 40 mg methylprednisolone). If graft rejection is severe, additional oral glucocorticoids (eg, prednisolone 1 mg/kg once daily) and sometimes intravenous glucocorticoids (eg, methylprednisolone 3-5 mg/kg once daily) are given. The rejection episode is usually reversible and graft function is fully restored. The graft may become nonfunctional if the rejection episode is severe or prolonged or after multiple rejection episodes. Retransplantation is possible, but the long-term prognosis is worse than with the first transplant.
[ Prognosis of corneal transplantation
The frequency of favorable long-term outcomes of corneal transplantation is more than 90% in keratoconus, corneal scars, early bullous keratopathy or hereditary stromal corneal dystrophies; 80-90% - in more developed bullous keratopathy or inactive viral keratitis; 50% - in active corneal infection; from 0 to 50% - in chemical or radiation injury.
The overall high success rate of corneal transplantation is related to many factors, including corneal avascularity and the fact that the anterior chamber has venous but not lymphatic drainage. These conditions contribute to low immunologic tolerance. Another important factor is the effectiveness of glucocorticoids used locally or systemically to treat graft rejection.
Corneal Limbal Stem Cell Transplantation
Corneal limbal stem cell transplantation surgically replaces deficient stem cells in the periphery of the cornea when host stem cells fail to regenerate following injury. Persistent, non-healing corneal epithelial defects can be caused by conditions such as severe chemical burns and severe contact lens intolerance. These defects result from the failure of corneal epithelial stem cells to regenerate. Untreated, persistent, non-healing corneal epithelial defects are susceptible to infection, which can lead to scarring and/or perforation. Corneal epithelial stem cells are found at the base of the epithelium at the limbus (where the conjunctiva meets the cornea). Because the corneal graft is used only in the central area of the cornea, treatment of persistent, non-healing epithelial defects requires corneal limbal stem cell transplantation. Corneal limbal stem cells can be transplanted from a patient's healthy eye or from a cadaveric donor eye. The patient's damaged corneal epithelial stem cells are removed by partial limbal excision (the epithelium and superficial stroma of the limbus). The donor limbal tissue is sutured into the prepared bed. The transplanted limbal epithelial cells form new ones that cover the cornea, healing its epithelial defects.