Cornea Transplantation is a surgical procedure in which a damaged or diseased cornea is replaced with healthy donor tissue. It helps restore clear vision, reduce pain, and improve the overall function and appearance of the eye.

Of all the tissue transplants performed in medicine, corneal transplantation is among the most successful and one of the longest established. Surgeons have been replacing diseased corneas with donor tissue for over a century, and the procedure has a track record that very few surgical interventions can match.
The cornea is the clear dome that covers the front of the eye. It contributes significantly to the eye’s focusing power and, more basically, it needs to be transparent for light to pass through to the retina at all. When disease, infection, trauma, or a genetic condition clouds or distorts the cornea, vision degrades in ways that glasses and contact lenses often cannot adequately correct. A transplant replaces the problem tissue with healthy donor cornea from someone who chose to donate their eyes after death.
What has changed most dramatically in recent decades is the surgical approach. Full-thickness transplants, where the entire corneal thickness is replaced, were once the only option. Now surgeons can selectively replace just the diseased layer while leaving the healthy layers intact.
A patient with Fuchs’ endothelial dystrophy, where only the inner cell layer fails, no longer needs a full-thickness graft. A patient with a deep stromal scar but healthy inner cells keeps their own endothelium. These selective techniques have transformed recovery times and long-term outcomes.
Corneal blindness affects an estimated 6.8 million people in India across at least one eye. The causes are somewhat different from the Western pattern: corneal scarring from herpes simplex and bacterial infections is more common here, partly reflecting the higher burden of infectious disease. Chemical injuries, trachoma (now declining but historically significant), advanced keratoconus, and surgical complications all contribute to the pool of patients needing transplantation.
The supply problem is acute. India performs roughly 40,000 corneal transplants a year, which sounds like a large number until you set it against the demand. Cultural hesitation about eye donation, limited awareness, and inconsistent retrieval systems mean that the country recovers far fewer corneas than it could. Patients wait. Some wait long enough that their condition deteriorates while they do.
| Procedure | Description | Best For |
|---|---|---|
| Penetrating Keratoplasty (PK) | Full-thickness corneal replacement | Extensive scarring, advanced keratoconus, full-thickness damage |
| DSAEK | Replacement of the endothelial layer with a thin posterior graft | Fuchs’ endothelial dystrophy, bullous keratopathy |
| DMEK | Replacement of only the Descemet membrane and endothelium | Fuchs’ dystrophy, endothelial failure with a clear stroma |
| PDEK | Thin pre-Descemet stroma included with the graft | Endothelial disease; technically easier to prepare than DMEK |
| DALK | Anterior stroma replaced while the host endothelium is preserved | Keratoconus and anterior stromal scars with healthy inner cells |
| ALK | Superficial replacement of the anterior corneal layers | Superficial scars, pterygium complications, band keratopathy |
In penetrating keratoplasty, the traditional approach, a circular trephine cuts through the full thickness of the diseased cornea and a matching donor button is sutured into the gap using extremely fine 10-0 nylon sutures. These sutures stay in place for a year or more while the graft heals. The central corneal surface is re-established by donor tissue from the start.
Endothelial keratoplasty, which covers DSAEK, DMEK, and PDEK, works through a small incision. The surgeon peels away the diseased inner layer of the host cornea and slides in the prepared donor disc through the incision. The disc is unfolded inside the eye and then held flat against the host cornea using an air or gas bubble injected into the anterior chamber. That bubble does the work a suture would do in PK, pressing the graft into contact while it adheres. No sutures cross the central cornea, which means less induced astigmatism and faster visual recovery.
DALK takes a different approach again. The front layers of the cornea are dissected away down to Descemet’s membrane, using air injected into the stroma to create a clean separation (the big bubble technique). Donor anterior stroma is then sutured in place, and the patient’s own endothelium is left completely untouched. Because the host endothelium is preserved, there is no risk of endothelial rejection, which is the most serious type.
| Procedure | Approximate Cost Range (INR) |
|---|---|
| Penetrating Keratoplasty (PK) | ₹50,000 – ₹1,20,000 |
| DSAEK | ₹60,000 – ₹1,50,000 |
| DMEK or PDEK | ₹70,000 – ₹1,80,000 |
| DALK | ₹60,000 – ₹1,40,000 |
Recovery after corneal transplantation tests patients’ patience more than almost any other eye surgery. After penetrating keratoplasty, vision improvement is gradual and unpredictable. The sutures distort the corneal surface while they are in place, and they need to be selectively removed over many months as the graft heals and the astigmatism pattern becomes clear. Full stabilisation can take a year or longer.
After endothelial keratoplasty, the picture is considerably better. No sutures cross the visual axis, and most patients notice meaningful improvement within two to four months. That said, the gas bubble used to hold the graft in the early post-operative period requires patients to lie face-up as much as possible in the first day or two, which is uncomfortable but important.
Graft rejection is a risk that does not disappear. It is most likely in the first two years but can occur at any time. Steroid drops are used long-term, sometimes indefinitely, to keep this risk as low as possible. The warning signs of rejection, sudden redness, pain, sensitivity to light, and a drop in vision, need to be treated as an emergency and not left until the next scheduled appointment.
Mayo Clinic. Cornea Transplant. https://www.mayoclinic.org/tests-procedures/cornea-transplant/about/pac-20385285
StatPearls, NCBI. Corneal Transplantation. https://www.ncbi.nlm.nih.gov/books/NBK539690/
Cleveland Clinic. Cornea Transplant. https://my.clevelandclinic.org/health/treatments/17714-cornea-transplant
PubMed. Outcomes of Corneal Transplantation. 2019. https://pubmed.ncbi.nlm.nih.gov/30969512/
A penetrating keratoplasty graft can function well for 15 to 20 years or longer in a suitable eye. Endothelial grafts also have good long-term data, with reasonable function documented at ten years in many patients. Lifespan depends on the underlying condition, how well the patient manages the drops, and whether any rejection episodes occur.
Yes, though less commonly than with solid organ transplants because the cornea is an immunologically privileged tissue. Rejection is treatable if caught early, which is why recognising the symptoms and acting on them quickly matters so much. Endothelial techniques carry a lower rejection risk than full-thickness PK.
It varies considerably by location and urgency. In cities with active eye banks, waits of a few weeks to a few months are typical for elective cases. Emergency situations such as corneal perforation are prioritised. In areas with fewer donations and less eye bank infrastructure, the wait is longer.
The sutures are extremely fine and most patients do not feel them. Occasionally a suture loosens or breaks, which causes localised irritation and needs prompt attention. This is one of the reasons regular follow-up after PK is important even when things seem to be going well.
Almost certainly yes, at least initially. PK often introduces irregular astigmatism that needs to be managed with glasses, contact lenses, or selective suture removal over time. After endothelial keratoplasty, the front corneal surface is largely unchanged and residual refractive error can often be corrected straightforwardly with spectacles.
Not your corneas; they are not suitable for re-transplantation. Other organs and tissues may still be donated. Eye banks assess each case individually.
Not during the procedure. Anaesthesia covers that. Post-operatively, mild discomfort, some sensitivity to light, and tearing in the first one to two weeks are normal. Severe pain is not expected and should prompt a call to the surgeon.
Penetrating keratoplasty typically takes 60 to 90 minutes. Endothelial procedures run 45 to 75 minutes. DALK can take longer depending on how straightforward the big bubble technique proves on that particular cornea.
Yes. They are done as separate procedures, usually weeks to months apart, so the first graft can be assessed before the second surgery is undertaken.
A comprehensive examination by a corneal specialist is the only way to know. If your vision cannot be adequately corrected with glasses or contact lenses and the cause lies in the cornea, transplantation is worth discussing. The assessment includes slit-lamp examination, topography, pachymetry, and an honest conversation about what is realistically achievable.
[FAQ section ends here]
References
Mayo Clinic. Cornea Transplant. https://www.mayoclinic.org/tests-procedures/cornea-transplant/about/pac-20385285
StatPearls, NCBI. Corneal Transplantation. https://www.ncbi.nlm.nih.gov/books/NBK539690/
Cleveland Clinic. Cornea Transplant. https://my.clevelandclinic.org/health/treatments/17714-cornea-transplant
PubMed. Outcomes of Corneal Transplantation. 2019. https://pubmed.ncbi.nlm.nih.gov/30969512/