Cornea Transplant

Cornea transplant, also known as keratoplasty is a surgical procedure in which part of your cornea will be replaced with corneal tissue from a donor.

Some facts about Cornea Transplant:

• Cornea is the transparent, dome shaped surface of your eye, where light enters your eye. It is a large part of the ability of your eye to see clearly.
• Vision can be restored, pain can be reduced and the appearance of a damaged or diseased cornea can be improved with a cornea transplant.
• Rejection of the donor cornea is a small risk of complications associated with cornea transplant.
• A cornea transplant is performed to restore vision of a person with a damaged cornea or to relieve pain or other signs and symptoms associated with cornea diseases.
• Keratoconus in which a cornea that bulges outward; thinning or tearing of the cornea; cornea scarring, caused by infection or injury, swelling of the cornea; corneal ulcers those are not responding to medical treatment and complications caused by previous eye surgery can be treated with a cornea transplant.
• Fuchs' dystrophy is a hereditary condition that can also be treated with a cornea transplant.
• Eye infection, glaucoma, problems with the stitches used to secure the donor cornea, rejection of the donor cornea, bleeding and retinal problems, such as retinal detachment or swelling are some of the possible risk of Cornea transplant.
• When the immune system of your body mistakenly attack the donor cornea, it is called rejection, and might require medical treatment or another cornea transplant.
• Loss of vision, eye pain, red eyes, sensitivity to light are the signs and symptoms of rejection.

Preparation for Cornea Transplant:

• You will have to undergo a thorough eye exam before cornea transplant surgery, in which your eye doctor looks for conditions that might cause complications after surgery.
• The size donor cornea you need will be determined by your eye doctor by taking the measurements of your eye.
• A review is required for all medications and supplements you are taking as you may need to stop taking certain medications or supplements before or after your cornea transplant.
• Unrelated eye problems, such as infection or inflammation, will be treated by your doctor before your surgery as it can reduce your chances of a successful cornea transplant.
• The corneas those are used in cornea transplants come from died people. However, corneas are not used from people who have died from unknown causes or from donors with certain conditions, such as diseases that can spread, previous eye surgery or eye disease.
• People needing cornea transplants do not require tissue matching, unlike with organs such as livers and kidneys.

Types of Cornea Transplant:

The entire thickness or partial thickness of the diseased cornea will be removed and is replaced with healthy donor tissue in Cornea Transplant. The type of method to be used in Cornea Transplant will be decided by your doctor.

Penetrating keratoplasty (PK):

Penetrating keratoplasty (PK) is a a full thickness cornea transplant in which cuts are made through the entire thickness of the abnormal or diseased cornea by your surgeon to remove a small button sized disk of corneal tissue.
The precise circular cut will be made by using a special instrument. The cut to fit donor cornea is placed in the opening. Then stitches or sutures are used by the surgeon to stitch the new cornea into place. These stitches will be removed in a later visit with your eye doctor.

Endothelial keratoplasty (EK):

Diseased tissue from the back corneal layers, including the endothelium and a thin layer of tissue that protects the endothelium from injury and infection will be removed in this procedure. The removed tissue will be replaced by the donor tissue.
Descemet stripping endothelial keratoplasty (DSEK) and Descemet membrane endothelial keratoplasty (DMEK) are  two types of endothelial keratoplasty.
Donor tissue are used to replace about one third of the cornea in DSEK where as a much thinner layer of donor tissue is used in DMEK. DMEK is  more challenging than DSEK as the tissue used in DMEK is extremely thin and fragile. But, it is commonly used.

Anterior lamellar keratoplasty (ALK):

Diseased tissue will be removed from the front corneal layers, including the epithelium and the stroma, while leaving the back endothelial layer in place.
The type of ALK procedure that is right for you will be determined by the depth of cornea damage.
Only the front layers of your cornea will be removed in superficial anterior lamellar keratoplasty (SALK), leaving the healthy stroma and endothelium intact. A deep anterior lamellar transplant (DALK) procedure will be used when cornea damage extends deeper into the stroma. The removed portion will then be replaced by grafting healthy tissue from a donor.

Artificial cornea transplant (keratoprosthesis):

Some people might receive an artificial cornea (keratoprosthesis) if they aren't eligible for a cornea transplant from a donor cornea.

Procedures for Cornea Transplant:

• You will either be given a sedative to help you relax and a local anesthetic to numb your eye, or to put you to sleep on the day of your cornea transplant.
• Surgery will be done on one eye at a time.
• The duration of time spent in surgery varies person to person depending on their health condition.

Recovery from Cornea Transplant:

• Eye drops or oral medications will be prescribed immediately after cornea transplant and during recovery to help control infection, swelling and pain.
• Eye drops can help prevent cornea rejections by suppressing the immune system.
• Wearing eye protection such as eye shields or glasses will help protect your eye as it heals.
• You might have to lie on your back for a while after surgery to help the new tissue stay in place depending on the type of transplant.
• Avoid rubbing or pressing your eye.
• You need to visit your eye doctor regularly in the year after surgery to monitor your progress and look for complications.