Cornea and External Eye Disease at the University of Washington

Surgical techniques in corneal surgery have improved dramatically over the last decade with more sophisticated operating microscopes and finer surgical instrumentation. The prognosis for a good surgical result in corneal transplantation is excellent in most cases.

Tueng T. Shen, MD, PhD and Michael Wu, MD of the University of Washington Cornea and External Disease Service specialize in surgical and medical management of corneal disorders, cataract surgery, and refractive surgeries.

Dr. Shen and Dr. Wu have extensive training and experience in Cornea and Refractive surgery. Their surgical and clinical expertise includes advanced techniques for cataract surgeries, corneal transplantation surgeries, anterior segment reconstruction, and management of corneal and external diseases. Dr. Shen performs refractive surgeries (LASIK, LASEK, PRK, and other surgical correction for refractive purposes, such as post transplantation). Dr. Wu performs LASIK and PRK for refractive purposes, as well as intracorneal ring (INTACS) implantation for keratoconus patients unable to wear contact lenses.

In the United States, approximately 30,000 patients receive corneal transplants each year. The waiting list for suitable transplantable donor material can be long, and there is always a need for more donor tissue. We are fortunate in the state of Washington to have the Lions' Sight and Hearing Foundation, an excellent eye bank in Seattle, that has tremendously improved the availability of donor material.

Listed below are Frequently Asked Questions about corneal transplantation, in general, and how donor tissue is obtained. Additional information about the cornea and corneal disease can be found by viewing this Fact Sheet from the National Eye Institute.

What is the Cornea?
The cornea is the clear front window of the eye. In its normal state, the cornea allows rays of light to pass through and be focused on the retina. The cornea is about as wide and thick as a dime and has a slight dome shape.
Many eye conditions affect the cornea and may change its transparency. Injuries, infection, inherited conditions, or aging changes may cause clouding or distortion of the cornea with decreased or distorted vision.
Sometimes the vision can be improved with glasses, a contact lens, or medications. However, when nonsurgical treatment fails, a corneal transplant may be necessary to improve vision.
A corneal specialist provides consultation, diagnosis, and treatment for the full range of medical and surgical conditions affecting the anterior segment of the eye. These include infections of the cornea, corneal decompensation, corneal dystrophies including Fuchs' dystrophy, keratoconus, corneal trauma and scarring, cataract, recurrent corneal erosions, pterygium, and dry eye syndrome.

What is a Corneal Transplant?
A central portion of the diseased cornea, approximately the size of a small shirt button, is removed at the time of surgery, as shown on the right, and replaced with a clear cornea donated by a person recently deceased. The new cornea is held in position with very fine suture material that may remain in place for months or years. After a corneal transplant, it may take some time for the vision to improve. The vision will be limited by corneal swelling and astigmatism. Astigmatism is an irregular corneal shape and affects every patient undergoing a corneal transplant. It may ultimately be necessary for one to have glasses or a contact lens in order to obtain the best sight possible. In general, some stitches may be removed between 3 and 6 months, and then additional sutures may be removed at a later time to minimize the astigmatism. Glasses are not prescribed until the cornea is sufficiently stable to give a substantial improvement in vision.

Who Needs a Corneal Transplant?
Any condition that causes permanent clouding or distortion of the cornea may result in poor vision and, therefore, require a transplant. There are other factors to consider in deciding who may benefit from this operation and at what time. The health of the rest of the eye is a key factor. If there is severe or irreversible retinal damage concurrent with the corneal disease, this may limit the potential of the eye to achieve good central vision. Glaucoma, or a high pressure in the eye, is often associated with corneal disease and may actually worsen after surgery. Other considerations include the vision in the opposite eye, whether the corneal condition is causing severe pain, and the relative prognosis for the specific condition that causes decreased vision in the eye being considered for a transplant. Additionally, any past eye surgery must be taken into account with regard to the effect it may have on further surgery.

How is Donor Material Obtained?
The donated cornea will come from a recently deceased person who had either decided to be an eye donor or whose family has made a humanitarian gesture in donating the eye so as to aid in the restoration of sight. The health of the donor material is carefully inspected before it is used, and screening tests are done to exclude transmittable diseases. If there is evidence of transmittable disease present, the corneas are not used.
To protect the privacy of the donor and his/her family, the details of the donation are not revealed. The donor tissue is placed in a special preservative solution which maintains the health of the donor cornea until the time of surgery.

What is the Purpose of an Eye Bank?
The eye bank is a nonprofit organization that sets a fee for transplantable corneal tissue, and covers the expense of obtaining, processing, and transporting the donor eyes. It acts as an intermediary between the next of kin for the patient donating his/her eyes after death and the eye surgeon who will perform the corneal transplant. The eye bank arranges to surgically retrieve tissue, antiseptically preserve it, and use various tests to assess the potential viability of the cornea if used for transplantation.

When Will the Stitches Be Removed?
In most cases, the stitches will be removed 3 months to 1 year after the operation. Some stitches may be left indefinitely. The stitches in an adult patient will be removed in the office after placing anesthetic (numbing) drops on the eye. Stitch removal in children is generally done under general anesthesia.

What Can I Expect in the Hospital?
The surgery is typically performed on an outpatient basis but some patients may be asked to stay overnight, depending on their other medical needs. The surgery is done under local or general anesthesia and may take from 1 to 3 hours.
Written instructions concerning medications and an appointment for the first postoperative visit will be given at the time of discharge from the hospital. The telephone number for appointments is (206) 598-4011.

What if my Cornea is Rejected?
Transplant rejection usually will not occur within the first 2 weeks after surgery. The major cause of early clouding of the transplant is not rejection but failure of the donated tissue to regain its vitality. If a rejection episode occurs, it is usually within the first month to 2 years after surgery. It is uncommon for a transplant to reject after 2 years, although this happens on rare occasion. If graft rejection occurs, more than half the time it can be reversed by early treatment with eye drops. The signs and symptoms of rejection are redness of the eye, increased light sensitivity, decreased vision in the eye, and pain the eye.

Business/Insurance-related Questions
Our patient care coordinators, Bruce Motter and Andrea DeCano, will assist patients in processing insurance forms and answer related questions. They can be reached at (206) 598-6918.

Summary
With modern techniques, corneal transplant surgery can, in most instances, restore useful vision to eyes affected by corneal diseases. While a guarantee of good vision cannot be made, the success rate from this procedure is now very high.
The Cornea Service at the University of Washington Eye Center will help in any way way possible to restore your vision. To schedule an appointment with one of our cornea specialists and surgeons, please call the UW Eye Center at (206) 598-4011.

For more information and to find an ophthalmologist near you, please click on one of the following links:
American Academy of Ophthalmology (AAO)
Eye Bank Association of America (EBAA)