A healthy, clear cornea is essential for good vision. If your cornea is damaged due to eye disease or eye injury, it can become swollen, scarred or severely misshapen and distort your vision. A cornea transplant may be necessary if eyeglasses or contact lenses can’t restore your functional vision, or if painful swelling can’t be relieved by medications or special contact lenses. A corneal transplant might also be required in cases of conditions such as trichiasis, where eyelashes turn inward and rub against the surface of the eye, causing scarring and vision loss.
A cornea transplant replaces diseased or scarred corneal tissue with healthy tissue from an organ donor. There are two main types of corneal transplants:
Penetrating Keratoplasty (PK)
Traditional, full thickness cornea transplant. During traditional corneal transplant surgery, a circular button-shaped, full-thickness section of tissue is removed from the diseased or injured cornea using either a surgical cutting instrument called a trephine or a femtosecond laser. A matching “button” from the donor tissue is then positioned and sutured into place. The sutures (stitches) remain in place typically for a year or more after surgery. Lastly, a plastic shield is placed over your eye to protect it during healing.
Endothelial keratoplasty (EK or DSEK)
In the past decade, a newer version of corneal transplant surgery has been introduced for certain corneal conditions. EK selectively replaces only the innermost layer of the cornea (endothelium) and leaves the overlying healthy corneal tissue intact. The endothelium controls the fluid balance in the cornea, and if it becomes damaged or diseased, this can cause significant corneal swelling and loss of vision. In EK, the surgeon makes a tiny incision and places a thin disc of donor tissue containing a healthy endothelial cell layer on the back surface of your cornea. An air bubble is used to position the new endothelial layer into place. The small incision is self-sealing and typically no sutures are required.
The most common type of EK procedure is called Descemet’s Stripping Endothelial Keratoplasty, or DSEK. The American Academy of Ophthalmology in 2009 endorsed DSEK as superior to the conventional full-thickness corneal transplant procedure (PK) for better vision outcomes and stability, as well as fewer risk factors.
EK has several advantages over full-thickness PK. These include: faster recovery of vision; less operating time; minimal removal of corneal tissue (and therefore less impact on the structural integrity of the eye and less susceptibility to injury); no related suture complications; and reduced risk of astigmatism after surgery.
Within a relatively short period of time, the EK corneal graft procedure has become the preferred technique for patients with Fuchs’ dystrophy and other endothelial disorders of the cornea. However, traditional full-thickness PK is still the most appropriate option when the majority of your cornea is diseased or scarred.
If you are experiencing corneal issues, please call 703.858.9800 and schedule a consult with our corneal surgeon.
A pterygium is an elevated, wedged-shaped bump on the eyeball that starts on the white of the eye (sclera) and can invade the cornea. Pterygia are benign (non-cancerous) growths, but they can permanently disfigure the eye. They also can cause discomfort and blurry vision.
Treatment depends on the size of the pterygium, whether it is growing and the symptoms it causes. Regardless of severity, pterygia should be monitored to prevent scarring that could lead to vision loss. If a pterygium is small, conservative treatments include lubricants or a mild steroid eye drop to reduce swelling and redness. Contact lenses are sometimes used to cover the growth, protecting it from some of the effects of dryness or potentially from further UV exposure. Topical cyclosporine also may be prescribed for dry eye.
If pterygium surgery is required, several surgical techniques are available. Your ophthalmologist will determine which is most appropriate for you. If needed, pterygium surgery is performed at an outpatient ambulatory surgery center.