What is Keratoconus? (brief, layman’s terms)
Keratoconus is a condition that causes the cornea (“window” to the front of the eye) to thin. As it begins to thin, the cornea starts to have abnormal areas that become steep. When light rays hit a cornea with steep areas and flatter areas, then the light rays scatter inside the eye causing blurry vision and light sensitivity.
Are some people more likely to develop it? (age, gender, risk factors)
Keratoconus usually starts to cause visual changes at younger ages (early teens to early 20’s) but in equal amounts with men and women. Those with a history of allergies, eczema, asthma and family history of Keratoconus have a higher risk of developing Keratoconus. There is a greater risk of the cornea thinning if someone tends to rub there eyes a lot, particularly if they rub their eyes with their knuckles.
How would someone know if they have it? (symptoms)
There are many people who have such a small degree of Keratoconus, that they are unaware/remains undiagnosed since they are still able to see well with glasses or contact lenses. However, if a person has vision that is changing often (many changes in eyeglass and/or contact lens prescriptions) this can be an indication of Keratoconus. Poor vision with new glasses and contact lenses can also be a warning flag.
How do eye doctors diagnose Keratoconus? (examine the eye, perform tests, equipment)
Keratoconus can be diagnosed by measuring the steepness and thickness of the cornea. A topographical map will measure high points and low points on the cornea giving us an indication of normal astigmatism (non-pathological) versus abnormal astigmatism (pathological). Normal astigmatism is present in 80% of the general population, thus, normal astigmatism is not an indicator for Keratoconus.
What consequences can occur if Keratoconus is left untreated?
If Keratoconus is progressive and left untreated, vision can deteriorate and scarring of the cornea can occur. If the cornea becomes too thin and scarred, a corneal transplant will become necessary to rehabilitate vision to a functional level.
Is Keratoconus always degenerative, or is it possible for it to stay at a mild level?
Keratoconus is not always degenerative or progressive. Nature has a way of making our whole body stiffer as we age, thus the cornea becomes stiffer and less apt to continue to thin. Additionally, extra caution to keep eye inflammation down (allergies, dry eyes, poorly fit contact lenses) are a must to encourage corneal stability.
How do you treat Keratoconus? Are there risks involved in the treatment?
There is no cure for Keratoconus, however, Collagen Cross-Linking (CXL) can slow or stop the progression of the disease. CXL is useful for those whose corneas are actively thinning/steepening but cannot reverse any damage or thinning that has already occurred. The purpose of this procedure is to strengthen the collagen bonds in the cornea. Those bonds are the “softest” at younger ages but will naturally start to harden/stiffen as one gets older. The CXL procedure does come with risks, however. Eye pain and blurry vision are expected following the procedure but there is also a risk of eye infection and scarring of the cornea. CXL has not shown to be beneficial for those whose corneas are stable. As for my personal experience, Keratoconus tends to stabilize in the 30’s.
Can keratoconus affect a person’s balance?
Because Keratoconus can cause vision to be unequal between the eyes, this can contribute to dizziness and/or loss of depth perception. With more severe cases of Keratoconus, an eyeglass prescription may help improve vision somewhat but the distortion from high amounts of astigmatism can be disorienting. Instead, specialty designed contact lenses can help alleviate the distorted vision one can get with eyeglasses. Corneal gas permeable lenses, hybrid (corneal gas permeable lens with a soft skirt) and scleral gas permeable lenses are generally the best means to provide clear vision for a person whose cornea has an abnormal shape like with Keratoconus.