Definition
When the cornea of the eye gets thinner and projects outward in a cone shape, an eye condition called keratoconus occurs.
Cornea is the clear, rounded, front surface of the eye.
The cone-shaped cornea that is formed when the keratoconus disease occurs makes the vision blurry and the eye becomes sensitive to light and shine.
Keratoconus normally affects both eyes. It usually affects people on the age between 10 and 25 and the condition can gradually develop for 10 years or longer.
The problems with the vision are easy to correct by simply wearing soft contact lenses or glasses. As the condition progresses, the person experiencing this condition may need to change to other type of lenses. If the condition is advancing and getting severe, cornea transplantation will be required to cure the eye condition of keratoconus.
Symptoms
The symptoms of keratoconus change as the disease progresses. They are the following:
- Blurry vision
- Distorted vision
- Greater light and glare sensitivity
- Problematic vision during the night
- Often eyeglass prescriptions changes
- Abrupt vision worsening because of corneal hydrops
Causes
What causes keratoconus is unknown, but it can be associated with:
- Forcefully rubbing the eyes
- Wearing contact lenses several years
- Retinitis pigmentosa
- Retinopathy
- Prematurity
- Vernal keratoconjunctivitis
- Combination of disorders such as enzyme abnormalities or hereditary factors as Down syndrome
Risk factors
Certain inherited diseases or genetic conditions, such as: Down syndrome, Leber’s congenital amaurosis, Ehlers-Danlos syndrome or osteogenesis inperfecta, may increase the risk of developing keratoconus. The risk is also higher if there is a history of keratoconus in the family.
Complications
Sometimes, the cornea may swell rapidly and provoke reduced vision and scarring of the cornea. If the keratoconus is advanced, the cornea may be scarred where the cone is formed. Scarred cornea will cause deteriorating problems with the vision and a transplant surgery may be needed. Daily vision problems can make a person anxious, so finding ways to adapt to the condition would be a good relieving measure.
Treatment
The treatment will differ according to the progressing rate and severity of the condition. Mild keratoconus doesn’t cause severe vision problems and doesn’t need to be treated additionally, so it can be easily treated with contact lenses or glasses. However, if the condition is advanced, i.e. wearing contact lenses becomes difficult or the cornea is scarred, a surgical treatment may be required.
In some cases, contact lenses are the solution. People often use:
- Eyeglasses
- Soft contact lenses
- Rigid gas permeable contact lenses
- Piggyback lenses
- Hybrid lenses
- Scleral contact lenses
On the other hand, if surgery is required, the following options exist:
- Corneal inserts-A surgery that includes insertion of two, tiny, clear, shaped like curved, plastic inserts into the cornea which can be removed later. The inserts restore normal corneal shape, slow the progress of keratoconus and diminish the need for transplantation. Also, they make the eye more tolerant and more fitting for contact lenses. It is a risky surgery as infection or injuries of the eye can happen during the surgical process.
- Keratoplasty (cornea transplantation)-It is a surgical procedure that is needed if a person’s cornea has thinned extremely or has been scarred. The cornea transplant can be partial (lamellar keratoplasty) in which only a part of the surface of the cornea is replaced; or it can be full (penetrating keratoplasty) in which entire portion is replaced with donor tissue. It can also be deep anterior lamellar keratoplasty which keeps the inner cornea layer and helps to avoid the rejection by endothelial cells that in a full-thickness transplant can happen. The recovery process can last up to a year and full improvement of the vision usually happens after several years. Cornea transplantation is generally a very successful treatment, but possible complications do exist. They are: poor vision, graft rejection, astigmatism, infection or incapability to wear contact lenses.
