This procedure uses donor tissue to restore vision and reduce pain from cornea disease. Our overview helps you understand the risks and benefits of this sight-saving operation.
A cornea transplant is an operation to replace part of the cornea with corneal tissue from a donor. This operation is sometimes called keratoplasty. The cornea is the transparent, dome-shaped surface of the eye. Light enters the eye through the cornea. It plays a large role in the eye's ability to see clearly.
A cornea transplant may:
Most cornea transplant operations are successful. But cornea transplant carries a small risk of complications, such as rejection of the donor cornea.
During a full-thickness cornea transplant, a circular disk-shaped portion of the cornea is removed and replaced with a similarly sized portion of cornea from a donor. This operation is called penetrating keratoplasty.
A cornea transplant is most often used to restore vision to a person with a damaged cornea. A cornea transplant also can relieve pain or other symptoms associated with cornea diseases.
A number of conditions can be treated with a cornea transplant, including:
The eye is a complex and compact structure measuring about 1 inch (2.5 centimeters) in diameter. It receives millions of pieces of information about the outside world, which are quickly processed by the brain.
Cornea transplant is relatively safe. Still, it does carry a small risk of serious complications, such as:
The body's immune system can mistakenly attack the donor cornea. This is called rejection. Rejection might require medical treatment or another cornea transplant.
Make an urgent appointment with your eye doctor if you notice symptoms of rejection, such as:
Rejection occurs in about 10% of cornea transplants.
Before cornea transplant surgery, you will undergo:
Corneas used in transplants come from people who have died. Corneas from people who died from unknown causes are not used. Corneas from people who had previous eye surgery, eye disease or certain conditions, such as diseases that are passed from one person to the next, also are not used.
Unlike people who need organs such as livers and kidneys, people needing cornea transplants don't require tissue matching. In the United States, donor corneas are widely available, so there's usually not a long waiting list.
A cornea transplant removes either the entire thickness or the partial thickness of the diseased cornea and replaces it with healthy donor tissue. Your cornea surgeon will decide which method to use. These types of operations include:
Penetrating keratoplasty. This operation involves a full-thickness cornea transplant. Your surgeon cuts through the entire thickness of the irregular or diseased cornea to remove a small button-sized disk of corneal tissue. A special instrument is used to make this precise circular cut.
The donor cornea, cut to fit, is placed in the opening. Your surgeon then uses stitches, also called sutures, to keep the new cornea in place. The stitches might be removed at a later visit with your eye doctor.
Endothelial keratoplasty. There are two types of endothelial keratoplasty. These operations remove diseased tissue from the back corneal layers. The layers include the endothelium and a layer of tissue called the Descemet membrane, which is attached to the endothelium. Donor tissue replaces the removed tissue.
The first type of operation, called Descemet stripping endothelial keratoplasty (DSEK), uses donor tissue to replace up to one-third of the cornea.
The second type of operation, called Descemet membrane endothelial keratoplasty (DMEK), uses a much thinner layer of donor tissue. The tissue used in DMEK is extremely thin and fragile. This operation is more challenging than DSEK but is commonly used.
Anterior lamellar keratoplasty (ALK). Two different methods remove diseased tissue from the front corneal layers, including the epithelium and the stroma. However, they leave the back endothelial layer in place.
The depth of cornea damage determines the type of ALK operation that's right for you. Superficial anterior lamellar keratoplasty (SALK) replaces only the front layers of the cornea. This leaves the healthy stroma and endothelium intact.
A deep anterior lamellar keratoplasty (DALK) operation is used when cornea damage extends deeper into the stroma. Healthy tissue from a donor is then attached to replace the removed portion of the cornea. This process is known as grafting.
Your doctor will discuss which method of cornea transplant surgery is best for you, tell you what to expect during the operation and explain the risks of the operation.
On the day of your cornea transplant, you'll be given a medicine to help you feel calm or less anxious or a medicine that numbs your eye. Either way, you shouldn't feel pain.
Surgery is done on one eye at a time. The amount of time spent in surgery depends on your situation.
After your cornea transplant, you can expect to:
Most people who receive a cornea transplant will have their vision at least partially restored. What you can expect after your cornea transplant depends on your health and the reason for your surgery.
Your risk of complications and cornea rejection continues for years after your cornea transplant. For this reason, see your eye doctor yearly. Cornea rejection can often be managed with medicines.
At first, your vision might be worse than it was before your surgery. Your eye needs time to adjust to the new cornea. It can take several months for your vision to improve.
It may take several weeks to several months after surgery for the outer layer of your cornea to heal. When it heals, your eye doctor will make adjustments that can improve your vision, such as: