When the cornea, the clear front window of the eye, becomes cloudy, scarred, or damaged beyond what any medication or laser can repair, a cornea transplant offers patients the chance to restore clear, functional vision. It is one of the most commonly performed and most consistently successful tissue transplants in human medicine, with outcomes that have improved dramatically with the development of partial-thickness surgical techniques.
Yet most patients who are referred for corneal transplant surgery have never heard the term before, do not know what the surgery involves, and arrive for their consultation with significant anxiety and unanswered questions. This complete guide from Dr. Kunal Nirmal (MS Ophthalmology) at Nirmal Eye Care Hospital, Bhavnagar, explains exactly how a cornea transplant works, the types, the procedure, the recovery, the risks, and what patients in Bhavnagar and across Saurashtra can realistically expect.
What Is the Cornea and Why Does It Need Transplanting?
The cornea is the transparent, dome-shaped tissue covering the front of the eye. It performs approximately two-thirds of the eye’s total focusing power and, as the outermost layer of the eye, also serves as a physical and biological barrier against infection, dust, and injury.
The cornea has five distinct layers: the epithelium, Bowman’s layer, stroma, Descemet’s membrane, and the endothelium. Each layer has a specific function, and disease or damage to any layer can cause the cornea to lose its transparency, leading to blurred vision or blindness that cannot be corrected with glasses, contact lenses, or laser surgery.
According to the News Medical scientific review of cornea transplant procedures, corneal disease is the fourth leading cause of blindness globally, after cataract, glaucoma, and age-related macular degeneration. In India, corneal blindness affects an estimated 1.5 million people, with a donor shortage meaning that patients often wait months to years for a suitable graft.
Who Needs a Cornea Transplant?
A cornea transplant is recommended when the cornea is so damaged or diseased that it cannot achieve adequate clarity or function through any non-surgical intervention. The most common conditions requiring corneal transplant in India include:
- Keratoconus: A progressive condition where the cornea thins and bulges forward into a cone shape, causing severe visual distortion that cannot be corrected with glasses. The most common reason for corneal transplant in young patients in India.
- Bullous keratopathy: Corneal endothelial failure causing the cornea to swell with fluid, resulting in severe clouding and pain. Often occurs after cataract surgery or from Fuchs’ endothelial dystrophy.
- Corneal scarring: From previous infections (particularly viral keratitis from herpes simplex or bacterial corneal ulcers), chemical burns, or physical trauma that has left permanent opacity in the visual axis.
- Fuchs’ endothelial dystrophy: A hereditary condition causing progressive loss of corneal endothelial cells, leading to fluid accumulation and corneal oedema.
- Corneal dystrophies: Inherited conditions causing progressive corneal clouding, including lattice, granular, and macular dystrophies that eventually require transplantation.
- Corneal ulcer with perforation: Severe infection or autoimmune ulceration that threatens the structural integrity of the eye may require emergency transplantation (tectonic keratoplasty) to preserve the eye.
- Failed previous corneal transplant: Graft failure from rejection or primary graft failure may require a repeat transplant procedure.
Types of Cornea Transplant Surgery
Not all cornea transplants are the same. The appropriate procedure depends entirely on which layer or layers of the cornea are diseased. Modern surgery has moved away from full-thickness transplantation in many cases toward selective layer replacement, which produces better outcomes and faster recovery.
PK – Penetrating Keratoplasty (Full Thickness)In the original corneal transplant, all five corneal layers are replaced with a full-thickness donor button. Still used when the entire cornea is diseased. The longest established technique with decades of outcome data. Recovery takes 12 to 18 months; sutures may remain for 1 to 2 years. Higher rejection risk than lamellar procedures. |
DSAEK: Descemet Stripping Automated Endothelial KeratoplastyThe most widely performed corneal transplant globally. Only the diseased endothelial layer and Descemet’s membrane are replaced via a thin donor disc inserted through a small incision. Recovery is faster than PK, rejection risk is lower, and the cornea is structurally stronger. Best for Fuchs’ dystrophy and bullous keratopathy. |
DMEK: Descemet Membrane Endothelial KeratoplastyThe most technically demanding and most anatomically precise endothelial transplant. Only the Descemet’s membrane and endothelium are transplanted without any stromal tissue. Produces the fastest visual recovery and lowest rejection rates of any corneal transplant type. Requires a highly skilled surgical team. |
DALK: Deep Anterior Lamellar KeratoplastyThe front layers of the cornea (epithelium, Bowman’s layer, and stroma) are replaced while the patient’s own endothelium is preserved. This eliminates endothelial rejection risk entirely, making it the preferred procedure for keratoconus and anterior corneal scarring when the endothelium is healthy. |
KPRO: Keratoprosthesis (Artificial Cornea)When biological tissue transplants have repeatedly failed or the patient has severe ocular surface disease that makes graft survival unlikely, an artificial corneal device (Boston KPro or Osteo-odonto-keratoprosthesis) may be considered. This is a highly specialised procedure performed at tertiary referral centres. |
Tectonic KeratoplastyAn emergency procedure to preserve the structural integrity of an eye that is at risk of perforation from severe infection, autoimmune ulceration, or trauma. The primary aim is to save the eye rather than restore vision, though visual improvement often follows once the eye is stabilised. |
How Does a Cornea Transplant Work
The exact procedure varies by type, but a standard penetrating keratoplasty or DSAEK follows this general sequence. Most cornea transplants in India are performed under local anaesthesia with sedation, or general anaesthesia for children or very anxious patients.
- Pre-surgical Assessment and Donor Tissue Preparation
Before surgery, the patient undergoes corneal topography, pachymetry (thickness mapping), anterior segment OCT, and retinal assessment to confirm the transplant is appropriate and the retina is healthy enough to benefit from surgery. Donor corneal tissue is assessed by an eye bank for cell density, clarity, and safety. The donor tissue is prepared in advance for the specific procedure type.
- Anaesthesia and Preparation
Local anaesthesia with a periocular or sub-Tenon’s block numbs the eye and prevents movement. Intravenous sedation keeps the patient comfortable and relaxed throughout. The eye is cleaned and draped, and a speculum holds the eyelids open. The operative field is prepared under a microscope.
- Removal of Diseased Corneal Tissue
For PK: a circular trephine (a hollow punch instrument) cuts a button of diseased cornea from the eye, creating an opening into the eye’s interior. For DSAEK/DMEK: only the diseased endothelial layer is stripped from the inside of the patient’s cornea using specialised instruments no full-thickness incision is made. For DALK: the front stromal layers are dissected and removed layer by layer while carefully preserving the endothelium below.
- Preparation and Insertion of Donor Tissue
For PK: a matching-size button is cut from the donor cornea and placed into the opening in the patient’s eye. For DSAEK: the donor disc is folded or rolled and inserted through a small incision using a specially designed injector, then unfolded inside the anterior chamber and positioned against the back surface of the patient’s cornea. For DMEK: an even thinner scroll of Descemet’s membrane and endothelium is inserted and unrolled inside the eye with careful air injection.
- Securing the Graft
For PK: the donor button is sutured into place with 16 interrupted sutures or a continuous running suture using 10-0 nylon sutures finer than a human hair. These sutures may remain in the eye for 12 to 24 months. For DSAEK and DMEK: no sutures are needed on the graft, and an air bubble is injected into the anterior chamber to press the donor tissue against the recipient cornea, where it adheres through fluid forces over 1 to 2 hours.
- Closure and Immediate Post-Operative Care
The wound is closed and checked for watertight integrity. A shield is placed over the eye. The patient rests face-up for 1 to 2 hours in recovery (critical for DSAEK and DMEK allows the air bubble to hold the graft in position). Most cornea transplant patients are able to go home the same day or the following morning.
Cornea Transplant Recovery Timeline
| Time After Surgery | PK (Full Thickness) | DSAEK / DMEK (Endothelial) | DALK (Anterior) |
|---|---|---|---|
| Day 1 | Rest, face-up positioning, no driving | Face-up 24 hrs is critical for graft adherence. | Rest; shield over eye. |
| Week 1 | Vision blurry; light sensitivity common | Significant improvement often visible by day 3 to 7. | Gradual clearing begins. |
| Month 1 | Vision improving but irregular | Many patients see 6/18 or better. | Clearer; sutures in |
| Month 3 to 6 | Suture adjustment may be needed. | Most patients reach near-final vision. | Vision stabilising |
| Month 6 to 12 | Selective suture removal begins. | Final prescription stable; glasses or contact lens fitted | Final vision is often excellent. |
| 12 to 24 months | All sutures removed; final prescription | Graft well established; annual monitoring | Long-term monitoring continues |
| Steroid drops | 1 to 2 years | 6 to 12 months (lower rejection risk) | 6 to 12 months |
Frequently Asked Questions
Is Cornea Transplant Surgery Painful?
The surgery itself is performed under anaesthesia and is completely pain-free during the procedure. After surgery, mild discomfort, foreign body sensation, and light sensitivity are common for the first few days and are managed with prescribed eye drops and pain relief. Significant pain after corneal transplant is unusual and should prompt immediate contact with your surgeon; it may indicate elevated eye pressure or infection.
How Long Does a Cornea Transplant Last?
A successful corneal graft can last for decades. DSAEK and DMEK grafts have 10-year survival rates of 75 to 85% in large studies. PK grafts that survive the first 5 years also have good long-term durability. The main threats to long-term graft survival are rejection episodes (which can be treated if caught early), progressive endothelial cell loss over time, and secondary glaucoma. Annual follow-up monitoring is important for life after corneal transplant.
Can Both Eyes Have a Cornea Transplant?
Yes, If both corneas are diseased, sequential bilateral transplantation is possible, typically performed as separate operations several months apart. Simultaneous bilateral surgery is generally not performed due to the small but real risk of bilateral complications. Patients with conditions like keratoconus or Fuchs’ dystrophy often ultimately need transplantation in both eyes over time.
How Is Corneal Transplant Different from Lasik Eye Surgery?
LASIK reshapes the existing cornea using a laser to correct refractive errors (short-sightedness, long-sightedness, and astigmatism) in a healthy cornea. Corneal transplantation replaces all or part of a diseased or damaged cornea with donor tissue when the cornea itself is no longer clear or functional. The two procedures address completely different problems. LASIK is an elective procedure for vision correction; corneal transplant is a medically necessary procedure to restore corneal clarity and function.