About the Cornea
The cornea is the clear part in the front of the eye. It allows light to pass through to the retina unobstructed. The curvature of the cornea bends the light rays and focuses them on the retina, producing clear images in normal vision.
Disease or trauma to the cornea can alter its structure and cause vision loss. Changes in corneal shape, thickness, or clarity cause poor vision that can often be corrected with a corneal transplant.
Corneal Transplant Surgery
During Cornea Transplant Surgery, a circle of tissue about 8mm in diameter is removed from the patient's cornea. It is replaced with corneal tissue from a human donor. The donor tissue is carefully screened to prevent transmission of disease to the recipient. The new donor cornea is stitched into position using very thin nylon thread. The sutures are barely visible and do not cause pain, although it is normal for the eye to feel scratchy or irritated for the first few days after surgery.
For the first few weeks after the surgery, the vision is usually blurry. After several weeks, the vision begins to clear. Within 3 or 4 months, new spectacles can be prescribed, which often sharpen the vision even more.
As with any type of surgery, there are risks in corneal transplant surgery. Infection or bleeding in the eye can be very serious problems, but rarely occur. Other risks include cataracts, retinal detachment, glaucoma, donor failure, and donor rejection. Most of these complications can be repaired surgically or controlled with medications. The doctor will discuss these risks in detail prior to surgery.
Corneal Transplant Pre-op, Post-op and Recovery:
- Pre-op: Prior to being accepted for transplant surgery at Corneal Associates, you will need to undergo a thorough eye exam to confirm that you will benefit from surgery. You are likely to be examined by more than one doctor. As with any surgery, it is best for you to be well rested and well hydrated before the procedure. You will also need to arrange for a family member or friend to escort you home after the procedure.
- Post-op: After the procedure, you will need to take it easy for several days. It is essential that you take the medicated drops prescribed to diminish the chances of infection. The stitches used in the procedure will be removed a few at a time. You will need to return to Corneal Associates several times.
- Recovery: It will take about 9 months for you to recover fully. During that time, you will need to protect the eye as much as possible with dark or shaded glasses. You will make several return visits to Corneal Associates so we can monitor your progress and remove stitches. In most cases, we are able to tell patients that they are fully recovered in 9 months to one year. In a few cases, we perform enhancements to remove scar tissue, and the recovery period can be longer.
Double Running Sutures
Corneal transplantation has evolved into a highly successful procedure. About 90% of patients experience improvement in their vision following this procedure. This surgery is usually performed on an outpatient basis, meaning patients do not have to spend the night in the hospital.
Dr. Perl may use a double running suture technique on his patients undergoing penetrating keratoplasty (PK). Double running sutures may lead to faster restoration of visual function in eyes that have undergone penetrating keratoplasty. The technique uses two continuous, parallel running 10-0 and 11-0 nylon sutures. Typically, the 10-0 suture is removed at eight to 12 weeks, which can allow for early visual restoration. Double running sutures also allow for better wound closure, fewer wound leaks, less astigmatism and lower incidence of rejection since the 11-0 thread is so fine and essentially inert.
NEW Corneal Transplant Procedure
Dr. Perl and Corneal Associates of New Jersey are excited to offer a new state-of-the-art procedure for patients in need of a corneal transplant. With some corneal diseases, the vision may become cloudy. This happens when the eye’s endothelial cells are damaged. These cells are located at the back of the cornea. Since only these cells are damaged, the patient can have a partial transplant.
About the New Method
Descemet's Stripping Endothelial Keratoplasty (DSEK) is the new method used during corneal transplant procedures. Corneal Associates of New Jersey is one of the few practices in the US to perform this advanced treatment. In DSEK, a surgeon uses special instruments to enter the cornea. Next, the surgeon removes the rear part of the cornea, called Descemet's Membrane. Once the damaged Descemet's Membrane has been removed, a donor membrane is inserted.
There are no stitches after the procedure, so fewer follow up exams are needed. Like many procedures, DSEK may not be appropriate for some people with particular corneal diseases. The knowledgeable staff of Corneal Associates of New Jersey can help decide if DSEK is appropriate for you.
When are corneal transplants recommended?
Corneal transplantation can help people who have vision loss due to disease or trauma of the cornea.
Corneal Transplants are Recommended for the Following Conditions:
Changes in corneal shape:The normal cornea has a fairly spherical curvature. In a disease known as keratoconus, the cornea can protrude outward forming a cone-like curvature, which causes visual loss. This disease is thought to be inherited, and usually begins to produce loss of vision sometime in the late teens and early adult years.
Contact lenses and glasses may improve vision in patients with keratoconus, but sometimes corneal transplantation is necessary to restore good vision. See our page on Keratoconus.
Changes in corneal thickness:Corneal edema, a build-up of fluid or swelling of the cornea, can result in loss of vision. This can occur as a result of cataract surgery or spontaneously due to corneal dystrophies or inflammation of the cornea. The cornea then becomes thickened and cloudy, obstructing the passage of light through the eye. When inflammation or infection is the causes of the edema, antibiotics or anti-inflammatory drops are prescribed to reduce the swelling. When the edema occurs after cataract surgery or is due to a dystrophy of the cornea, a corneal transplant is often necessary.
Changes in corneal clarity or opacity of the cornea: The normally clear cornea can become cloudy due to scarring after an injury or an infection. The scar tissue prevents the clear passage of light through the cornea, resulting in a loss of vision. Sometimes scar tissue can be removed with a laser (excimer laser phototherapeutic keratectomy or PTK). When the scar extends into the deeper corneal tissues, a corneal transplant is usually necessary to restore vision.