Our eyes have a clear protective barrier against germs, dirt, and other harmful things. It is called the cornea, and it can be damaged through injuries, infection and other factors, distorting our vision. In fact, there is a disease which can change or distort the shape of the cornea, called keratoconus. This disease may affect out daily lives, as it thins our cornea and may result in blurry vision. As you read further into this article, you will learn more about the causes, symptoms and treatments for keratoconus. So keep reading and feed your mind with insightful ideas regarding this disease.
Keratoconus: What Is this Illness?
As mentioned, keratoconus is a condition wherein there is a gradual thinning of the cornea. When the cornea begins to become thin, it bulges out, forming an unnatural rounded cone shape which brings light rays out of focus. The deformed curvature of the cornea may lead to nearsightedness (myopia), blurred vision, increased sensitivity to light and astigmatism.
Causes of Keratoconus
The cause of keratoconus is yet unknown, but according to some studies, it is most likely due to a combination of genetic vulnerability along with hormonal and environmental factors. Moreover, new research suggests that the corneal tissue’s enfeebling may be caused by a deficiency in an enzyme in our cornea. This deficiency causes the cornea to be more vulnerable to oxidative damages caused by free radicals.
In addition, this condition is also connected to excessive rubbing of the eyes, lingering irritation of the eyes, poorly fitted contact lenses and overexposure to UV (ultraviolet) rays emitted by the sun.
Symptoms of Keratoconus
The progressive distortion of the cornea triggers irregular astigmatism and nearsightedness, which develops greater problems with blurred and distorted vision. A person with keratoconus will also experience light and glare sensitivity, eye strain, eye irritation, eye redness or swelling, headaches and general eye pain.
Treatments for Keratoconus
One of the treatments for keratoconus includes the use of lenient contact lenses/eyeglasses for the early stage. But as the cornea continues to thin and change in shape, rigid gas spongy contact lenses can be prescribed to correct the vision. Listed below are some of the possible treatments for keratoconus:
Piggybacking contact lenses
Gas-permeable contact lenses dome above a cone-shaped cornea can be uncomfortable. That’s why some eye care experts practice “piggybacking” two varieties of contact lenses in one eye. You can do this by placing a soft lens over the eye before fitting a gas permeable lens over that soft lens. This increases the comfort of the wearer, since the soft lens acts like a suppressing pad under the stiff GP lens.
Custom soft contact Lenses
Custom soft contact lenses are actually made to correct the mild-to-moderate effects of keratoconus. These lenses are usually made-to-order, based on the measurements of the patient’s eye(s).
Semi-scleral and scleral lenses
These are a larger version of the gas permeable type of contact lenses. The fact that they larger means they rest even more on the sclera. On the other hand, the semi-scleral lenses encompass a smaller area than the scleral. These kinds of lenses are more comfortable, as they don’t apply pressure to the cone-shaped cornea.
Gas permeable contact lenses
If the use of eyeglasses or soft contact lenses may not manage the progress of keratoconus, there are gas permeable types of contact lenses. This type contact lense domes above the cornea, replacing its unnatural shape with a smooth, uniform bending surface to improve vision.
Corneal cross-linking (CXL)
This treatment is also called corneal cross-linking of the collagen and it has two versions: epithelium-on & epithelium-off. The epithelium-off method removes the crosslinking of the outer layer of the cornea. This is to allow the entry of vitamin B and riboflavin into cornea, which will eventually activate with UV light. On the other hand, the epithelium-on process allows the corneal epithelium to still be intact during the treatment. It usually requires more time for the riboflavin to enter into the cornea, but it is way better because it prevents the risk of infection and it promotes faster visual recovery. The use of CXL treatment reduces the necessity for various corneal transfers for keratoconus patients.
Topography-guided conductive keratoplasty
This treatment involves the use of radio waves applied on several points in the corners of the cornea to reshape it. Essentially, a topographic map is made by the computer imaging of the eye’s surface, helping create individualized treatment plans.
This kind of treatment is surgically applied. A tiny plastic insert is placed just beneath the eye’s surface in the edge of the cornea to reshape it for clearer vision. This kind of treatment is applicable if there is no other way to obtain satisfactory vision with eyeglasses or contact lenses.
Those who have keratoconus can’t tolerate firm and irritating contact lenses. Or there might be no other choices, as other therapies can no longer offer a satisfactory vision. Thus, the last option will be a transplant of the cornea. After the transplant, the patient will likely need glasses for clearer vision.