Keratoconus Correction and Treatment with Contact Lenses
Keratoconus is a condition whereby the cornea gradually thins and becomes misshapen. The cornea surface becomes irregular similar to the shape of a cone from the pressure of the eye causing vision loss. The cornea is the clear "window" part of the eye, in front of the pupil and colored part of the eye, called the iris. The vision resulting is similar to looking through an ice cube.
Although the cause of Keratoconus remains unknown, biologic and metabolic changes to the cornea have been observed. Incidence amongst the population is about 1 out of 2,000 to 4,000. Family histories of Keratoconus have been reported with an incidence of less than 1 - 2%. Cases of Pellucid Marginal Degeneration which is similar to Keratoconus , but has a wider thinning of the cornea has been documented in families with a slightly higher incidence.
Keratoconus Causes Irregular and Oblique Astigmatism - The trademark shape is the pointy and irregular shaped cornea.
Keratoconus can begin in teenage years, from thirteen to fifteen years of age, but generally starts later in the low to mid twenties. Many mild cases of Keratoconus go undiagnosed. Eyeglasses or soft contact lenses can correct early stages of Keratoconus . In later stages of the disease, Vision can become blurred within a few years whereby driving vision can not be attained without treatment. Untreated advanced cases past five years can result in blindness.
* With the advent of Laser Refractive Corrective surgery, many cases of Keratoconus are being diagnosed with the associated consultation. Laser Refractive Corrective surgery can not be performed on an eye with Keratoconus due to the thinness of the cornea.
Progression of Keratoconus
Early onset of Keratoconus in teenage years can progress rapidly and cause the cornea to become conical within a few years time span. Keratoconus with teenage onset can advance to include scarring and Neovascularization of the cornea. Neovascularization is a condition where blood vessels grow into the cornea from the cornea thinning causing vision impairment.
If vision loss is significant, a Keratoplasty (cornea transplant) may have to be performed. If Neovascularization is present, transplantation of a new cornea can have rejection difficulties. Use of immunosuppressants have been known to be successful to avoid rejection difficulties.
More common is later onset of Keratoconus . Keratoconus onset in your twenties generally does not progress as rapidly and many times stabilizes before thirty years of age. Individual cases can vary and many will have normal vision with the use of specialized contact lenses and some vision with the use of eyeglasses. In extreme cases where the cornea is scarred, and a specialized contact lens can no longer restore vision, a corneal transplant may be required.
C-Kone contact lens
C-Kone lenses are gas permeable contact lenses specially designed for the treatment of Keratoconus . They are fitted from a fitting kit that allows perfect duplication of size. The design of these lenses mimic the shape contours that Keratoconus presents. After treating Keratoconus for twenty years and cataloging all the variable shapes, we have defined quite precisely what shapes that are required. The shape is cut into the contact lens using a state of the art Coburn lathe with aspheric curve generation. Aspheric curves are like a stair case with no sharp step edges. The lens material that we currently supply is Boston XO. This lens material has superior oxygen transmission. C-Kone lenses are 9.6 millimeter in diameter and each have a 6 millimeter optic zone. This allows full vision even in low light settings. Precise definition of fit, maximized optic zone and breathing of the lens all add up to a beautifully comfortable lens with excellent visual results.C-Kone contact lens featuresMulti - curve aspheric fitting that is computer contour blended
Large optic zone for superior vision
Large "foot pad" for increased comfort for long days
Excellent night vision, no glare
Good movement for tear exchange
Expandable for wide range of fittings
Will fit advanced stages of Keratoconus
High oxygen material for cornea "breathing"
Other contact lens corrections
Primary correction of Keratoconus is with gas permeable contact lenses. Other types of contact lenses for the correction of Keratoconus include:
Soft contact lenses designed specifically for Keratoconus
Piggy back soft contact lenses to "carry" a gas permeable lens
Softperm lenses - a soft lens with a hard center
Scleral contact lenses that cover a large portion of the cornea
Synergeyes KC - New high oxygen transmission hybrid soft lens with a gas permeable center specifically designed for Keratoconus
Novakone - New soft contact lens designed specifically designed for Keratoconus More Info
Surgical treatment options
Cornea Cross Linking (C3R) - is a procedure that was developed in Germany. The procedure consists of using UV light with Riboflavin (vitamin B2) in an attempt to bond the structural layers together to increase strength. There are currently studies being performed in North America to determine the efficacy of this procedure.
Intacs - are plastic strips that are implanted into the cornea to help reshape the optic surface.
Cornea transplantation - is performed when the vision can no longer be restored with contact lenses. Cornea transplants replace the window of vision to allow light to pass through again.
In the past Keratoconus was often a blinding disease. Today, treatment has improved with many advanced contact lenses available. In the past fifteen years, we have treated hundreds of Keratoconus patients with C-Kone contact lenses allowing them normal vision. We have found that fully 90% of all Keratoconus patients have had success wearing C-Kone contact lenses producing adequate vision and many times 20/20 vision. Transplantation of corneas has become an extremely rare vision correction requirement.
Fittings of Keratoconus normally require several visits over a period of 2 to 8 weeks. More difficult cases can take 3 to 9 months for a complete fitting.
The proper spelling is "Keratoconus", to enable improper spellings to access this web-site on search engines, some alternative misspellings are Kerataconus , keratconus, ceratoconus, cerataconus, ceratakonus and ceratokonus.