Corneal Transplants Performed at Our Jacksonville, FL Practice
The cornea is the clear tissue in the front part of the eye. It is made of three primary layers: the Epithelium, the corneal stroma, and the Endothelium. The epithelium is a thin surface layer. The stroma is a thick transparent middle layer composed of collagen fibers. The endothelium is a single layer of specialized cells that pumps fluid out of the corneal stroma and keeps it clear. Too much fluid in the stroma can cause swelling of the cornea and decreased vision.
What is Corneal Transplant Surgery?
When the cornea loses its clarity and transparency due to scarring, swelling or abnormal blood vessel development, a corneal transplant can to performed to restore vision and reduce pain and discomfort.
A corneal transplant is a surgical procedure where part of your cornea is replaced with a donor cornea. Conditions that can be treated with corneal transplant include:
- Keratoconus (Abnormal bulging of the cornea)
- Anterior corneal dystrophies (Lattice dystrophy, granular dystrophy)
- Posterior corneal dystrophies (Fuchs dystrophy)
- Corneal Ulcers
- Corneal scarring (from injury or infections)
- Thinning of the cornea
- Complications from previous corneal surgeries or disorders
Corneal transplant is a relatively safe and successful procedure. However, it does carry a small risk of serious complications such as eye infection, problems with the stitches used to secure the donor cornea, increased pressure in the eye (glaucoma), cataract formation, or rejection of the corneal tissue.
Types of Corneal Transplants
- Full-Thickness Corneal Transplant
- In full-thickness corneal transplant surgery, the surgeon removes the entire diseased corneal tissues with a circular “cookie cutter” type instrument. The cornea is then replaced with a precisely matched donor corneal tissue with the aid of tiny hair-like sutures.
- Partial-Thickness Corneal Transplant
- Partial-thickness corneal transplant is performed when only a certain layer of the cornea is affected by a disease. The patient’s own healthy, properly functioning corneal layers are left in place. These types of the procedure include:
- Endothelial keratoplasty
- Anterior lamellar keratoplasty
- Partial-thickness corneal transplant is performed when only a certain layer of the cornea is affected by a disease. The patient’s own healthy, properly functioning corneal layers are left in place. These types of the procedure include:
Endothelial Keratoplasty (EK)
EK involves removing the diseased back layer of the cornea: The endothelium along with the Descemet membrane. The donor tissue is then carefully prepared and implanted to replace the removed corneal tissue. An air or gas bubble is placed under the graft to hold it in position. No sutures are used to hold the graft in place. If the graft does not adhere sufficiently, a “re-bubble” procedure to re-inject the gas or air bubble may be necessary within the first few weeks after the initial procedure.
There are two types of endothelial keratoplasty. The most common type is called Descemet stripping automated endothelial keratoplasty (DSAEK). In this surgery, the donor tissue consists of the endothelium, Descemet membrane and a small amount of stroma.
A newer type of procedure, called Descemet membrane endothelial keratoplasty (DMEK), uses a much thinner layer of donor tissue (No stroma). Because the tissue used in DMEK is extremely thin and fragile, this procedure is more challenging than DSAEK and is performed not as commonly.
Anterior Lamellar Keratoplasty (ALK)
This procedure removes the diseased front corneal layers, including the epithelium and the stroma, but leaves the back endothelial layer in place.
Recovery after corneal transplant:
Recovery after a corneal transplant surgery generally takes several months to a year. Recovery depends on the reason for your surgery, your health, type of corneal transplant, your body’s wound healing time, corneal astigmatism and refractive errors. In some cases, patients may wear glasses or a rigid, hard contact lens over the corneal transplant to improve vision.
Your risk of complications and cornea rejection continues for years after your cornea transplant. For this reason, it is very important to see your eye doctor annually.
Signs and symptoms of corneal rejection include:
- Redness
- Sensitivity to light
- Decrease in Vision
- Pain
These symptoms can be remembered by the acronym RSVP. It is important to inform your eye doctor immediately if you notice any of the signs and symptoms of corneal rejection. Majority of the time, the rejection episodes can be successfully treated with medical treatment.
Post-Surgical Care for Your Corneal Transplant
In the first few weeks following surgery, particular care needs to be taken to avoid putting any pressure or strain on the affected area. The stitches can remain in place for up to a year-and-a-half following surgery. During the follow-up period, the ophthalmologist may also alter the sutures in the area to minimize any sight problems (astigmatism) caused by the irregular surface the transplant provides.
As the time since the surgery increases, the swelling and blurring, which are common effects of the surgery, will subside. Many people find that the transplant area remains thicker than the surrounding tissue and may be slightly raised. For most patients, their corneal transplants are healed and working well about a year after surgery.
How is Vision Improved by Corneal Surgery at Our Jacksonville, FL Practice?
Most people will find that their vision improves after surgery. Some sight problems, such as astigmatism or nearsightedness will remain, as the transplant will never completely match the depth and curvature of the rest of the cornea. These problems can normally be corrected with contact lenses or glasses.
Transplant patients normally need to wait around three months, or until all the stitches are taken out, to be tested for new prescription lenses. As a separate procedure, patients may wish to have laser vision correction (PRK or LASIK). Following laser correction, individuals often find that they are able to dispense with, or reduce the use of, their corrective vision aids.
The right choice of contact lens following corneal transplant surgery is important, in order to minimize corneal swelling at the same time as improving vision. We normally recommend appropriate lenses on a patient by patient basis, but types that usually work well include hybrid lenses, GP (gas permeable) or RGP (rigid gas permeable) lenses. In some cases, soft contact lenses may also be used.