Keratoconus can be defined as the name of the disease which results in progressive thinning of the cornea. As a result of this disease the cornea changes from a round shape into a cone shape, thus causing distortion of the focus of light as it enters the eye.
Although it is hard to pinpoint the specific causes of Keratoconus, certain predisposing factors can be responsible.
Atopic Disease –People who have a history with atopic diseases like asthma and severe allergies that calls for steroid injections are associated with Keratoconus.
Hard or Gas Permeable Contact Lenses –Wearers of such lenses show a higher risk of Keratoconus. Were the lenses responsible for the condition or did the condition pre-exist from the beginning? - The answer pertaining to this question is the same as the answer for: Did the chicken come first or was it the egg?
Rubbing one’s eye vigorously –People who are suffering from Keratoconus are known to have a habit of serious eye rubbing.
Genes – Genes are also responsible for causing Keratoconus. The chances of developing this disease are higher in the case of twins, people suffering from Down’s syndrome and families having a history of Keratoconus.
Hormones – The disease has been shown to progress more rapidly in the case of pregnant women and teenagers during their adolescent years.
Studies differ on the incidence but on average, 2 to 86 people out of every 100,000 people suffer from this disease.
Signs and Symptoms of Keratoconus
At times Keratoconus patients may not even realize that they are suffering from this disease for a long period of time. They attribute their suffering to distorted vision, blurry vision, glare problems and also sensitivity to light. As their cornea continues becoming more conical, they also become more and more nearsighted, showing more myopia and astigmatism.
A lot of times a simple solution like wearing glasses can help Keratoconic patients out. As time goes by, it can become more and more difficult for the patients to have a 20/20 vision using prescription glasses. As long as the patients are still able to function and drive vehicles normally using glasses, they can continue to wear glasses.
Toric Soft Contact Lenses – These are perfect for patients having Keratoconus during their initial stages. If popular brands such as Air Optix, Acuvue Advance for Astigmatism aren’t an option there are many less familiar brands that can work just as well and have the higher powers necessary for a keratoconic person.
Gas Permeable Contact Lenses –These are ‘hard’ contact lenses which are used by patients suffering from Keratoconus. In the case of this kind of lenses, tears are trapped between the back of the lenses and the cornea. These tears play the role of lenses themselves and help in smoothening out irregularities on the cornea. A pair of standard gas permeable contact lenses usually does the trick in a lot of cases.
Specialty Gas Permeable Contact Lenses –After the individual has reached an advanced stage of Keratoconus, the tip or apex of the cornea’s conical portion would rub on the standard gas permeable contact lenses. This might cause scarring or abrasions on the cornea and it would be very painful. In such a scenario specialty lenses would be a savior because they have a special pocketed part that parallels the shape of the cone. A popular design in this case would be the Rose K lens. These were designed by Dr. Paul Rose, an optometrist from New Zealand. A lot of other companies have their own versions of the Rose K lens, so you can choose between them. Another good example would be Ikone lenses.
Scleral and Semi-Scleral contact lenses –These are used by experienced optometrists for the purpose of getting the perfect fit. The scleral lenses vault the cornea as a whole and tears would act as a lay to smooth out the peaks and valleys of the front of the eye. This kind of lens correct the irregularity of the cornea and is generally very large in size, it would extend past the cornea, to the white portion of the eye.
Piggyback contact lenses –These are basically a set of two lenses. Out of the two lenses, the softer one is directly put on to the eye while the harder or gas permeable one is worn on top of the soft lens. While the softer lenses provide cushioning for the cornea, the harder one would facilitate better vision. Piggyback lenses can be used by the wearer intermittently when they experience from wearing just their hard contact lenses.
Hybrid contact lenses –At present SynergEyes is the only company in the market that manufactures hybrid lens. This type of lens is similar to the gas permeable one since it as a soft portion called the ‘skirt’. This kind of lens offer the functionality of the gas permeable lens with the comfort offered by a soft lens – best of both worlds indeed. While the ClearKone lens may be effective and comfortable, it is harder to put in and take out in addition to being pricier.
Intacts – These are small plastic inserts which are embedded into one’s cornea. It props the cornea up in order to create a more conventional or normal surface. Getting intacts is a quick procedure and the end result is the potential freedom from specialty contact lenses and glasses. Even though these aren’t effective in eliminating the condition, they certainly can delay the need for a cornea transplant surgery.
Corneal Crosslinking -Here a riboflavin solution is used under particular wavelengths of UV light for bonding and strengthening the cornea in order to prevent steepening or increasing of the corneal deformation. This surgery can be done by removing the top layer of the cornea (epithelium) or the solution can be applied directly on to the epithelium. Both of these methods are effective.
Cornea Transplant –This is the last resort for those suffering from Keratoconus. Here the cornea is cut out surgically and replaced with a donor cornea and this is then sewn into place properly. The duration of the healing period can be anywhere from a couple of months to a year or more. The transplant recipient will ultimately still need to wear specialty contact lenses in most cases.