Corneal collagen cross-linking is an important intervention in the Treatment of Keratoconus. We have learnt that Keratoconus is a disease with onset at puberty. The cause of Keratoconus can vary. It than progresses for next few decades. Progression of keratoconus leads to thinning and bulging of cornea. The distorted cornea causes various aberrations leading to poor functional vision. In many cases the cornea can rupture. The only rehabilitation in such cases can be performed with corneal transplants. The goal of a Keratoconus doctor is to prevent this major procedure. This can be achieved by Corneal collagen cross-linking by riboflavin. Cross linking of the cornea makes it stronger.
The idea of Corneal collagen cross-linking to strengthen the cornea
Keratoconus is a weakness of the cornea . Weakness can also develop in plastics. Chemical engineers use cross linking to strengthen weak plastics. Keratoconus experts and researchers were fascinated with this observation. They thought Cross-linking may make the cornea stronger. Strength of cornea is measured by Young’s modulus which is defined as stress/strain. Experiments showed that it took more force or strain to stretch the cornea which had been cross linked. This concept was taken from the lab to the real world.
Gold Standard of Corneal collagen cross-linking for Keratoconus
The inventors of Corneal collagen cross-linking tried various combinations in the lab and in clinical practice. They found the most effective treatment for cure of Keratocconus was epithelium off Corneal collagen cross-linking with riboflavin. So this is the current gold standard against which all other methods and variations have to be tested. We will learn and explore them in the section on variations of Corneal collagen cross-linking
Steps in Corneal collagen cross-linking with Riboflavin procedure
The top most layer of the clear part of the cornea is termed epithelium. It prevents fluids and bugs from entering the cornea. This has to be removed to allow riboflavin to penetrate the cornea. Riboflavin is applied. Finally it is activated by UV A radiation. For details how cross linking is perforemd see Corneal collagen cross-linking with Riboflavin procedure
Who is a good candidate for Corneal collagen cross-linking?
Every young person should be treated with Corneal collagen cross-linking with Riboflavin procedure at the time Keratoconus is diagnosed.Not everyone can be fortunate enough to undergo this process and halt keratoconus. The thickness of the central cornea has to be above four hundred microns. The shape is another determining factor. The effect is best observed when the curvature of the cornea is best between fifty two and fifty seven diopters. It should be still be performed if the curvature is less than fifty two. The central cornea should also be free of scars and folds.
One or both eyes – Cornea collagen cross linking with Riboflavin
In the United States we prefer to do one eye at a time. The healing is slower than lasik eye surgery. This decreases the time to be taken off from school or work. You can play video games sooner. Some European surgeons perform both eyes at the same time. For out of town patients that may be a consideration,
Variations of Corneal collagen cross-linking for Keratoconus
Methods are being investigated where epithelium may not be removed. It is weakened to allow passage of riboflvain.This is termed epi on or epithelium on corneal cross linkage. Iontophoresis may help in this process.
Pulsed Oxygen delivery is beinginvestigated to decrease procedure time. Iris registration and tracking to allow focal variations in Riboflavin and UV radiation are in trials. Finally chemicals are than riboflavin are being researched.
Corneal collagen cross-linking combined with Intacs for treatment of Keratoconus.
Intacs corneal ring segments can be implanted at the same time. This allows faster recovery of vision.
To learn more about pain free Corneal collagen cross-linking done by a Keratoconus expert please contact us.