Corneal Collagen Cross-Linking
The Newest Treatment for Keratoconus
Keratoconus is a condition that affects the cornea, which is the outermost part of the eye. The transparent, dome-shaped cornea helps to protect the eye, but it also functions as a lens to focus incoming light onto the retina to provide clear vision. The cornea’s thickest layer, called the stroma, contains collagen. Collagen is a type of protein that is abundant in the body. It consists of tightly packed molecules that form long, thin fibers that give strength and structure to cells and tissue.
In eyes that develop keratoconus, the corneal collagen becomes unstable. This causes the cornea to become weaker and thinner and to bulge forward, creating an irregular cone-like shape. With the natural shape of the cornea altered, vision is affected. The first symptoms associated with keratoconus, which may include slight blurring or distortion of vision and increased sensitivity to light, may be mild. However, the condition is progressive, which means without treatment it worsens over time. Symptoms may advance to include starbursts around lights, ghosting, multiple images, intense glare or severe blur and distortion. Keratoconus tends to first appear in individuals in their late teens or early 20s. In some eyes, it may progress for many years and then stabilize. In others, approximately 10-20% of keratoconus sufferers, it may eventually reach a point at which a corneal transplant is necessary to restore useful sight.
The cause of keratoconus isn’t completely understood. It’s thought that the condition could be related to genetics, hormones, insufficient elimination of cell metabolism byproducts from the body, atopic (allergic) disease, or a combination of factors.
Corneal Collagen Cross-Linking Can Stabilize Vision
The FDA recently approved a new treatment for keratoconus called corneal collagen cross-linking (also known as KXL). KXL isn’t a cure for keratoconus, but it’s the first treatment that’s capable of stopping its progression, preventing the need for a corneal transplant. A large number of studies have shown that KXL prevents further loss of vision for most patients and improves vision for many.
While KXL is newly approved for use in the United States, it has been performed on more than 200,000 eyes around the world.