What is the Cornea?
The cornea is the clear window at the front of the eye. It forms the rounded front of the eye and is responsible for helping properly focus light. Thankfully, most people have a clear, healthy cornea; however, there can be several conditions that affect this critical piece of the eye and significantly impact your eye health. A corneal specialist can help diagnose and discuss treatment options for any of these conditions and more.
Common Conditions involving the Cornea
Severe Dry Eye
Dry eyes can be debilitating and affect more and more people today as the demands on our eyes increase. Although conservative measures can often improve the situation, some cases require additional treatment, such as prescription drops or in-office procedures to improve the discomfort and blurred vision than can happen with dry eyes. Some patients with systemic conditions such as Sjogren syndrome, Lupus, or rheumatoid arthritis may also have severe dry eye that requires additional treatment. If you have symptoms that are not responding to initial treatment, a corneal specialist may be able to help.
Corneal ulcers are infections on the surface of the eye. These are usually rare but can be more common in contact lens wearers or following trauma to the eye. These are often caused by bacteria but can be caused by viruses, fungi, or other atypical organisms. Corneal ulcers need to be diagnosed and treated quickly because even a few days without treatment can lead to worsening vision and scarring of the cornea. Talk to your eye doctor immediately if you are worried about a developing eye infection.
Keratoconus and post-LASIK ectasia
The cornea is usually rounded and clear; however, in a condition called keratoconus, the cornea weakens and begins to thin and bulge forward, mimicking the shape of a cone. Unfortunately, this process can significantly decrease the clarity of vision even with glasses or contact lenses. This disease can run in families and is associated with eye rubbing. A corneal specialist can screen for keratoconus using a topography or tomography test which takes a picture of the curvature of the cornea. The earlier keratoconus is diagnosed, the better visual outcomes can be. Patients with worsening keratoconus can now get a procedure called corneal crosslinking (CXL) which strengthens the cornea and can stop keratoconus from progressing. In advanced cases, patients may need a special contact lens or even a corneal transplant for better vision.
Fuchs Dystrophy (endothelial dystrophy) is a condition characterized by progressive damage to the inner lining of the cornea, the endothelium. This layer of cells is responsible for keeping the cornea clear and regulates the amount of water in the cornea. If the layer is damaged, then the cornea can swell and turn cloudy, which can interfere with good vision. In advanced stages, the cornea can become painful due to fluid accumulating. Thankfully, few patients reach this stage today due to advances in corneal transplant surgery. A partial thickness (endothelial) transplant can replace a layer of damaged cells with a donor layer and restore both function and vision. There are different ways to perform this surgery, such as DSEK and DMEK, and a corneal specialist can discuss whether surgery is right and what options may work best for you.
Corneal scars can occur from old infections or trauma and can interfere with good vision. Even if it has been many years since the scar formed, there may be treatments that can improve the quality of vision. There have been improvements in hard contact lenses that can improve vision in certain circumstances. Some treatments can also include laser resurfacing in the case of surface scars, or partial thickness corneal transplants that can replace the scarred cornea with healthy clear tissue. It is best to discuss options with your corneal surgeon to find out if anything can be done for your condition.
Pterygia are red vascular growths on the surface of the eye which can expand over the surface of the eye to distort the surface of the eye or even cover the pupil. These are commonly associated with sun and wind exposure or chronic dry eyes. A pterygium can get irritated or inflamed and can progress over time to cause visual changes. In these cases, they can be surgically removed with significant cosmetic and visual improvement.
Corneal dystrophies are rare, genetically associated disease that can appear earlier in life and progress over time. Sometimes patients are aware of other family members who may have similar findings; however, at times, the diagnosis can be subtle. In certain cases, patients need treatment that may include laser resurfacing or corneal transplantation. Talk to one of our experts if you have a family history of a corneal dystrophy or have been diagnosed with one to learn more about your options.
Advances in surgical techniques and technologies have pushed the field of cornea surgery further and further in recent decades. We now have options to heal or replace the specific parts of the cornea that are diseased, only affecting what is necessary and decreasing the amount of time your eye needs to heal. Even though the thought of eye surgery can be scary, when it is necessary to restore vision, you can have peace of mind knowing that all of the best options are available to you. Here are some of the procedures our surgeons have experience with:
- Full thickness corneal transplant (Penetrating keratoplasty)
- Removal of all layers of the cornea and replacement with a full thickness corneal donor. Usually this is done for full thickness damage to the cornea, such as after trauma, or in a severe scar or corneal dystrophy
- Partial thickness corneal transplants (DMEK, DSEK, DALK)
- A partial thickness corneal transplant can be done for many conditions such as Fuchs dystrophy or scars in the front part of the cornea. By removing only the layer with the issue healing and visual outcome can be improved in these cases.
- Corneal crosslinking (CXL)
- Corneal crosslinking is an in-office procedure to strengthen the cornea in cases of worsening keratoconus or ectasia following laser refractive surgery. This procedure can help to stabilize the surface of the eye and prevent the need for a more invasive surgery.
- Laser vision correction (LASIK, PRK, PTK)
- Laser vision correction can treat many levels of nearsightedness and farsightedness with excellent results. In addition, laser resurfacing (PTK) can be used to laser away some corneal scars. Make an appointment with a corneal specialist to learn more about your options and testing to see if you are a candidate for laser correction options.
- Superficial keratectomy
- A superficial keratectomy is usually an in-office procedure to remove irregularities on the surface of the cornea. These are usually bumps in the surface layer of the cornea that interfere with clarity of vision, and smoothing the surface of the eye can make the cornea more regular.
Specialty Contact Lenses
Even when surgery is not an option or not desired, improvements in contact lens technology mean that we can improve vision for many patients with new forms of contact lenses such as rigid gas permeable (RGP) lenses, hybrid contact lenses, or scleral contact lenses. These forms of lenses have a harder center that helps to treat conditions that may have left an irregular surface such as corneal scars, infections, or trauma. Even if you have used RGP lenses in the past without success, advances in technology may mean that you can see better and more comfortably than before. A corneal specialist can let you know if a specialty contact lens is right for you and refer you to one of our contact lens specialists who fits these special types of lenses.