Keratoconus in an Eye

What is Keratoconus?

Keratoconus is an uncommon condition in which the cornea (the clear front window of the eye) becomes thin and protrudes. Keratoconus literally means “cone-shaped cornea.” This abnormal shape can cause serious distortion of vision.

What Causes Keratoconus?

Despite continuing research, the cause of keratoconus remains unknown. Although keratoconus is not generally considered an inherited disorder, the chance of a blood relative having keratoconus is thought to be as high as 1 in 10. Vigorous eye rubbing, although not the cause of keratoconus, can contribute to the disease process. Therefore, patients with keratoconus are advised to avoid rubbing their eyes.

What Are the Symptoms of Keratoconus?

Blurring and distortion of vision are the earliest symptoms of keratoconus. Symptoms usually appear in the late teens or early twenties. The disease will often progress slowly for 10 to 20 years, and then stop. In the early stages, vision may be only slightly affected, causing glare, light sensitivity and irritation. Each, eye may be affected, differently.

Chart Illustrating Keratoconus in an Eye

As the disease progresses and the cornea steepens and, scars, vision may become distorted, A sudden decrease in vision can occur if the cornea swells. The cornea swells when the elastic part of the cornea develops a tiny crack, created by the strain of the cornea’s protruded cone-like shape. The swelling may persist for weeks or months as the crack heals and is gradually replaced by scar tissue.

How is Keratoconus Treated?

Mild cases are successfully treated with glasses or specially designed contact lenses (see scleral lenses below). When vision is no longer satisfactory with glasses or contact lenses, surgery, usually a corneal transplant is recommended. Other surgeries such as special heating of the cornea (thermokeratoplasty) or adding additional corneal tissue (epikeratophakia) can also be done.

If sudden corneal swelling occurs, your ophthalmologist may prescribe eye drops for temporary relief. However, there are no medicines known which prevent progression of the disease. If a corneal transplant is necessary for advanced keratoconus, vision usually improves. As in any eye surgery, complications such as transplant rejection, infection, and loss of vision can occur, so results cannot be guaranteed.

Scleral Contact Lenses

Scleral lenses are specially designed, highly breathable gas permeable (“hard”) contacts. They are ideal for patients with irregular, hard-to-fit corneas or special ocular surface needs. These lenses are comfortable, and allow for a level of vision correction that far surpasses traditional soft contacts or glasses. Instead of resting on the pupil, like other GP lenses, scleral lenses vault over the entire corneal surface and rests on the sclera (the white part of the eye). If you find traditional GP lenses are ill-fitting or dislodge easily in your eye, sclerals might be a great option for you. For any particular questions regarding scleral lenses, talk to your eye doctor here at West Georgia, or call our contact lens technician, Teresa Stewart: 706-507-7633.