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What is Keratoconus?

Keratoconus is a progressive disorder that is characterized by cone-shaped outward bulging and thinning of the cornea, leading to distorted vision in relation to asymmetrical irregular astigmatism where the smooth surface of the cornea becomes slightly wavy and myopia that develops when the front of the cornea expands.

It can occur in one or both eyes, and often begins during a person’s teens or early 20s.

What are the symptoms?

At the onset of keratoconus, you may not experience any symptoms and your vision may only slightly be affected. The earliest signs are usually blurred vision and frequent changes in eye glass prescription, or vision that cannot be corrected with glasses.

Some of the other symptoms include: 

  • Sudden change of vision or double vision in just one eye
  • Haloes around bright lights
  • Ghosting of images
  • Increased sensitivity to bright lights and glare

The diagnosis is confirmed by a corneal topography, which maps the surface curvature of the cornea.

You may already know you have Keratoconus.

How is Keratoconus Treated?

The treatment for keratoconus may vary depending on the stage of the disease, but rigid gas-permeable (RGP) contact lenses are often selected as a first choice to help mask the underlying irregular cornea. However, contact lens intolerance occurs in some eyes because of the compromised cornea or complications due to allergic conjunctivitis.

In such cases, patients may consider surgical treatments such as corneal transplant, intrastromal corneal ring segments and the corneal collagen cross-linking for treatment of the corneal irregularities. As for the short-sightedness caused by keratoconus, you may consider phakic intraocular lens implantation, which is the Visian Implantable Contact Lens (Visian ICL™).

Visian ICL™, a posterior chamber phakic intraocular lens that has been reported to be the premium vision correction surgery for moderate to high refractive error, may therefore be an option for patients with stable keratoconus. One such successful case was the Visian ICL™ implanted in Steven Holcomb, a bob sled pilot from team USA. Due to keratoconus, Holcomb’s vision was once as bad as 20/1000. His vision improved to almost 20/20 after surgery, allowing him to see things on tracks that he never knew were there before.

Why is LASIK not for you?

Procedures such as LASIK or PRK can be very dangerous for even a small degree of keratoconus because both surgeries remove tissue from the cornea in order to reshape it to the desired curvature. This will further weaken the structural integrity of the cornea and worsen the progression of keratoconus

What are your options?

Glasses
At the onset of keratoconus, prescription glasses can correct the myopia and astigmatism. However, as the cornea becomes irregular, vision is no longer adequately corrected with glasses.
Contact Lenses
There are various contact lenses available for people with keratoconus.
 
In the earlier stages of keratoconus, soft contact lenses are used to provide clear vision. As the keratoconus progresses and soft contact lenses are not sufficient, Rigid Gas Permeable (RGP) becomes the main option for correcting the vision. These lenses mask the irregularities of the cornea, with tears between the lens and the cornea. 

Other types of contact lenses include:
    • Hybrid Lens, where an RGP center is surrounded by a soft peripheral “skirt”
    • Scleral Lens, which are larger diameter lenses that rest on the white part of the eye and vaults over the cornea. 
Implantable Contact Lens

Visian ICL™ is a lens placed within the eye and is made of Collamer, which is similar to collagen. Rather than altering the shape of the cornea by thinning the corneal tissue as in LASIK, the Visian ICL™ is easily inserted into your eye behind the iris through a tiny self-healing wound of 2.5 mm. The cornea where light enters the eye is kept pristine. Visian ICL™ is made of a soft foldable material called Collamer, which is similar to collagen found in our bodies naturally. Hence the lenses are bio-compatible and are never rejected by the body.

One such successful case was the Visian ICL™ implanted in Steven Holcomb, a bob sled pilot from team USA. Due to keratoconus, Holcomb’s vision was once as bad as 20/1000. His vision improved to almost 20/20 after surgery, allowing him to see things on tracks that he never knew were there before.

Have you been turned away from LASIK or PRK because the doctor diagnosed you with keratoconus? Well that does not mean that you can never be free of contacts or glasses. You may still be suitable for Visian Implantable Contact Lens (Visian ICL™), a reversible vision correction option that keeps your cornea pristine.
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