KERATOCONUS

WHAT IS KERATOCONUS?

Keratoconus is a progressive thinning and weakening of the cornea. The cornea is the clear outer layer of the eye that helps protect the eye and also helps focus light rays onto the retina. Thinning of the cornea causes an abnormal cone-shaped bulge on the surface of the eye which may lead to loss of vision. Keratoconus generally affects both eyes although it is not unusual for one eye to be worse than the other.

WHAT CAUSES KERATOCONUS?

The cause of keratoconus is not fully understood but it appears there may be a genetic association. Keratoconus has been linked to several other medical conditions such as hay fever, asthma and sleep apnoea. Continuous eye rubbing and poorly fitted contact lenses have also been connected with the condition.

WHAT ARE THE COMMON SYMPTOMS?

Initially, there is a barely noticeable irregularity of the cornea that progresses to a bulge on the eye surface. When the cornea becomes misshapen vision changes such as blurring, sensitivity to light or seeing halos or ghost-like images, may occur.

CAN IT BE TREATED?

Depending on the progression of the condition and other factors there are several treatment options for keratoconus including contact lenses, glasses and corneal cross-linking.

WHAT DOES CORNEAL CROSS-LINKING DO?

Corneal cross-linking is a surgical procedure that is effective in slowing down or halting the progression of keratoconus. Riboflavin, also known as vitamin B2 is applied to the cornea and activated by ultraviolet light to form new cross-links between the collagen fibres. These new cross-links make the cornea more rigid, which helps stop the thinning of the cornea and further loss of vision.

HOW IS CORNEAL CROSS-LINKING PERFORMED?

Corneal cross-linking takes about an hour and is performed as an office procedure. Patients may experience some mild discomfort immediately after the treatment.

The “epi-on” treatment option leaves the epithelial layer of the cornea intact. With this treatment option patients often experience less pain and recover more quickly.