What is Corneal Collagen Cross Linking (CXL) ?

Corneal cross-linking (CXL) is a procedure to prevent progression of keratoconus. It does not treat or cure keratoconus. Keratoconus is a condition in which the cornea becomes weak, thin, and irregularly shaped. This causes the cornea to bulge forward in the shape of a cone, resulting in poor vision.

Normal corneas have cross-links between their collagen fibers. These keep the corneas strong and prevent them from developing irregular shapes. In those with keratoconus, the cross-links are too few, and the resulting lack of structure allows the cornea to bulge outward. During the cross-linking procedure, additional cross-links are added, which provides a more significant structure to the cornea and makes it more stable.

CXL is the most effective treatment to prevent the progression of keratoconus, but it must be diagnosed relatively early. If the condition becomes too advanced, the corneas will be too thin or scarred, and CXL may no longer be an option.

How is CXL performed?

CXL is an outpatient procedure that must be performed by a corneal specialist. During the procedure, you will lie flat on your back while looking up at a soft blue light. The surgeon will apply vitamin eye drops (riboflavin) in your eyes and then expose the eyes to ultraviolet light.