Corneal transplantation, also known as keratoplasty, is one of the most important and effective procedures in ophthalmology. It involves the surgical replacement of a cloudy or damaged cornea with a healthy donor cornea. The cornea is the transparent, domed part that covers the front of the eye and plays a critical role in the refraction of light, allowing clear and sharp vision. In cases where the cornea loses its clarity, normal curvature or functionality, vision is dramatically reduced and can even lead to blindness. Corneal transplantation provides a solution to these situations, giving many patients the ability to see clearly again.
The cornea and its importance in vision
The cornea is the “window” of the eye. It is colourless and transparent, acting like a lens that allows light to pass through the eye and focus on the retina. Its health and clarity are essential for good vision.
Corneal disorders can be caused by:
- Hereditary conditions (e.g. keratoconus)
- Infections (bacterial, viral, fungal)
- Injuries or chemical burns
- Degenerative lesions
- Surgical procedures that led to clouding
When medication and conservative methods fail, corneal transplantation is the only solution.
Indications for corneal transplantation
The decision to have a corneal transplant is made when vision cannot be improved with glasses, contact lenses or other treatments.
The main indications are:
- Keratoconus: This is a progressive condition in which the cornea thins and becomes conical in shape, causing severe astigmatism and reduced vision.
- Corneal scars: Can result from trauma, infections (e.g. herpes) or chemical burns.
- Corneal dystrophies: Such as Fuchs dystrophy, which leads to loss of endothelial cells and swelling.
- Extensive clouding after interventions: In some cases of cataract or glaucoma surgery.
- Infections resistant to treatment: When drugs and interventions fail.
Types of corneal transplantation
There are different types of keratoplasty, depending on which part of the cornea needs to be replaced:
1. Penetrating Keratoplasty (PK)
This is the classic transplantation, where the entire thickness of the cornea is replaced with a healthy donor.
2. Anterior partial thickness keratoplasty (DALK)
In this technique, only the anterior part of the cornea is replaced, preserving the patient's endothelium. It is mainly indicated for keratoconus.
3. Posterior partial thickness keratoplasty (DSAEK, DMEK)
It involves replacement of the endothelium only, useful in Fuchs dystrophy and other endothelial diseases.
The choice of method depends on the condition, age, needs and health of the patient.
Process of transplantation
The procedure is performed under local or general anesthesia and lasts about 1-2 hours. The donor cornea is taken from eye banks and subjected to special testing.
The surgical technique involves the removal of the damaged tissue and the placement of the new cornea, which is fixed with tiny sutures. New partial-thickness techniques use thinner incisions, with faster recovery.
Results and success rates
Corneal transplantation has high success rates, ranging from 80% to 95%, depending on the condition and type of surgery.
- In keratoconus, success rates are extremely high.
- In dystrophies, especially with DMEK, the results are spectacular with rapid recovery.
- In infections or wounds, success rates are lower, due to a higher risk of rejection.
Patients often get vision improved enough to return to their daily activities.
Complications
Despite its success, corneal transplantation is not without risks. The most common complications are:
- Graft rejection: the immune system may recognise the new tissue as foreign.
- Infections: Rare, but serious.
- Astigmatism and refractive errors: glasses or laser may be needed for correction.
- Relapse of the original disease: In some conditions there is a risk of recurrence.
Regular monitoring by an ophthalmologist is crucial for the early treatment of any problems.
Postoperative care and rehabilitation
Post-operative care plays an important role in the success of the surgery. The patient is given special drops (cortisone, antibiotics) for several months and must avoid injuries or strenuous activities.
Full stabilization of vision may take 12-18 months, especially in penetrating keratoplasty. Stitches are removed gradually. In many cases, correction with glasses or contact lenses is required for the best visual outcome.
Life after corneal transplantation
Most patients report a significant improvement in their quality of life after surgery. They can return to work, drive and enjoy daily activities with fewer restrictions.
Following the doctor's instructions, patience in recovery and regular medical monitoring are the keys to success.
