Keratoconus

When the normally round cornea (front part of the eye) becomes thin and cone-shaped, a vision disorder call keratoconus occurs. This abnormal shape of the cornea prevents the light that enters the eye from being focused correctly on the retina and causes vision distortion.

In the early stages of keratoconus, the patient will experience slight blurring, distortion of vision and increased sensitivity to glare and light. The symptoms usually appear in the late teens or late 20s and the condition may progress for 10-20 years and then gradually slow.

Each eye can be affected differently. As keratoconus progresses, the cornea increasingly bulges and vision may become more distorted. In a few cases, the cornea has been known to swell and cause a sudden and significant decrease in vision. The swelling occurs when the pressure of the cornea’s protruding cone shape causes a tiny crack to develop. It may last weeks or months while the crack heals and is gradually replaced by scar tissue. In the event of this sudden swelling occurring, your optometrist can prescribe eye drops for temporary relief, but there is no medication that will prevent the disorder from progressing.

The mild short-sightedness and astigmatism caused in the early stages of keratoconus can be corrected with eyeglasses or soft contact lenses. But as the condition progresses and the cornea continues thinning and changing shape, rigid gas permeable contact lenses can be prescribed to restore adequate vision. In most cases this will be sufficient. The contact lenses must be carefully fitted and frequent checks and lens changes may be needed to achieve and maintain good vision.