Dry eye syndrome is caused by a chronic lack of sufficient lubrication and moisture on the surface of the eye. Its consequences range from subtle but constant irritation to inflammation of the anterior (front) tissues of the eye. Dry eyes also are described by the medical term, keratitis sicca, which generally means decreased quality or quantity of tears. Kerato conjunctivitis sicca refers to eye dryness affecting both the cornea and the Conjuctiva.
Tiny fibers of protein in the eye called collagen help hold the cornea in place and keep it from bulging. When these fibers become weak, they cannot hold the shape and the cornea becomes progressively more cone shaped.
Keratoconus appears to run in families. The condition happens more often in people with certain medical problems, including certain allergic conditions. It’s possible that the condition could be related to chronic eye rubbing. Most often, though, there is no eye injury or disease that can explain why the eye starts to change.
A corneal transplant involves replacing a diseased or scarred cornea with a new one. When the cornea becomes cloudy, light cannot penetrate the eye to reach the light-sensitive retina. Poor vision or blindness may result.
In corneal transplant surgery, the surgeon removes the central portion of the cloudy cornea and replaces it with a clear cornea, usually donated through an eye bank. A trephine, an instrument like a cookie cutter, is used to remove the cloudy cornea. The surgeon places the new cornea in the opening and sews it with a very fine thread. The thread stays in for months or even years until the eye heals properly (removing the thread is quite simple and can easily be done in an ophthalmologist’s office). Following surgery, eye drops to help promote healing will be needed for several months. The chances of success of this operation have risen dramatically because of technological advances, such as less irritating sutures, or threads, which are often finer than a human hair; and the surgical microscope. Corneal transplantation has restored sight to many, who a generation ago would have been blinded permanently by corneal injury, infection, or inherited corneal disease or degeneration.
A cornea transplant is performed to improve the function of the cornea and improve vision. If pain is caused by a significantly diseased or damaged cornea, a cornea transplant may relieve that symptom.
With these factors in mind, you also should consider several important questions before you decide to undergo a corneal transplant:
- Your functional vision impede your job performance or your ability to carry out daily activities
- Your vision corrected with special contact lenses or other less invasive measures
- the cost of cornea transplant surgery affecting your financial situation if your vision insurance does not cover everything from pre-screening to post-operative consultations
- All of these issues, in conjunction with a thorough screening and consultation with your eye doctor, must be carefully considered before you make the final decision to have a corneal transplant.
No, your eye color stays exactly the same. The transplant involves only the transparent clear cornea and not the colored part of the eye (iris).
A cornea transplant, also called keratoplasty, is a surgical procedure to replace part of your cornea with corneal tissue from a donor. Your cornea is the transparent, dome-shaped surface of your eye that accounts for a large part of your eye’s focusing power.
A cornea transplant can restore vision, reduce pain and improve the appearance of a damaged or diseased cornea.
Most cornea transplant procedures are successful. But cornea transplant carries a small risk of complications, such as rejection of the donor cornea.
Total cornea transplant recovery time can be up to a year or longer. Initially, your vision will be blurry for the first few months — and in some cases may be worse than it was before — while your eye gets used to its new cornea. As your vision improves, you gradually will be able to return to your normal daily activities. For the first several weeks, heavy exercise and lifting are prohibited. However, you should be able to return to work within a week after surgery, depending on your job and how quickly your vision improves. As with any type of surgery, you have to follow the instructions of your eye surgeon to help minimize corneal transplant complications and expedite healing.
Experts know more about the long-term success rates of penetrating cornea transplants, which use all the layers of the cornea.
Success rates are also affected by the problem that needed to be fixed with the transplant. For example, research has found that the new cornea lasts for at least 10 years in:
89% of people with keratoconus
73% of people with Fuchs’ dystrophy
60% to 70% of people with corneal scarring
In the past decade, a newer version of corneal transplant surgery called endothelial keratoplasty (EK) has been introduced for certain corneal conditions.
Endothelial keratoplasty selectively replaces only the innermost layer of the cornea (endothelium) and leaves the overlying healthy corneal tissue intact. The endothelium controls the fluid balance in the cornea, and if it becomes damaged or diseased, this can cause significant corneal swelling and loss of vision.
In EK, the surgeon makes a tiny incision and places a thin disc of donor tissue containing a healthy endothelial cell layer on the back surface of your cornea. An air bubble is used to position the new endothelial layer into place. The small incision is self-sealing and typically no sutures are required.