Keratoconus is a condition in which the cornea progressively thins and bulges outward. Normally the cornea is round but in keratoconus it takes on the shape of a cone. Doctors do not know for sure why people have keratoconus. In some cases, it appears to be genetic (passed down in families). About 1 out of 10 people with keratoconus have a parent who has it too.
Keratoconus often starts when people are in their late teens to early 20s. The vision symptoms slowly get worse over a period of about 10 to 20 years. Keratoconus often affects both eyes, and can lead to very different vision between the two eyes. Symptoms can differ in each eye, and they can change over time.
Keratoconus usually takes years to go from the early to late stage. However, for some, keratoconus can get worse quickly. The cornea can swell suddenly and start to scar. When the cornea has scar tissue, it loses its smoothness and becomes less clear. As a result, vision grows even more distorted and blurry.
In the early stage, keratoconus symptoms can include:
Mild blurring of vision
Slightly distorted vision, where straight lines look bent or wavy
Increased sensitivity to light and glare
Eye redness or swelling
In later stages, keratoconus symptoms patients experience:
More blurry and distorted vision
Increased nearsightedness or astigmatism (when your eye cannot focus as well as it should). As a result, you may need new eyeglass prescriptions often.
Not being able to wear contact lenses. They may no longer fit and they are uncomfortable.
Do not rub your eyes! — Rubbing your eyes can damage thin corneal tissue and make your symptoms worse.
How Is Keratoconus Diagnosed?
Keratoconus can be diagnosed through a routine eye exam. Your ophthalmologist will examine your cornea, and may measure its curve. This helps to show if there is a change in its shape. Your ophthalmologist may also map your cornea’s surface, corneal topography, or pentacam, using a special computer. This detailed image shows the shape of the cornea and can help diagnose even very early cases of keratoconus.
Keratoconus treatment depends on your symptoms. When your symptoms are mild, your vision can be corrected with eyeglasses. Later you may need to wear special advanced contact lenses (RGP or scleral lenses) to help keep vision in proper focus.
If special contacts cannot achieve good vision, your ophthalmologist might suggest the following treatments:
Intacs This is a small curved device that your ophthalmologist surgically puts in your cornea. Intacs help flatten the curve of your cornea to improve vision.
Collagen cross-linking Your ophthalmologist uses a special UV light and eye drops to strengthen the cornea. Doing this helps to flatten or stiffen your cornea, keeping it from bulging further.
Corneal transplant If keratoconus is severe, your ophthalmologist may suggest a corneal transplant. Your ophthalmologist replaces all or part of your diseased cornea with healthy donor cornea tissue. The surgeons at Northeast Ohio Eye Surgeons use the most advanced techniques for corneal transplantation in keratoconus, such as DALK and PK. DALK preserves the innermost layer of the cornea, provides a speedier recovery and prevents transplant rejection.