CLE Contact Lenses

Keratoconus is a non inflammatory progressive genetic disorder that results in the thinning of the cornea. It often causes irregular astigmatism, is bilateral, and is the product of alterations in the structure of the collagen fibrils in the middle layer of the cornea. Frequently, there is scarring and reduced vision and in the later stages of the disease there can be pain if corneal hydrops occur. The same findings appear when ectasia occurs post operatively in LASIK.

In 1999 researchers in Germany performed the first cross linking procedure to halt the progression of Keratoconus. The surgery involves debrading the corneal epithelium and introducing riboflavin ( vitamin B) followed by UVA light exposure. Riboflavin protects the posterior cornea, lens and retina from exposure to the UVA. The target tissue is the anterior 300 um of the stroma thereby increasing collagen strength. This has shown to delay and in some cases even stop the progression of the corneal thinning. The increased collagen fiber diameter and repopulation of keratocytes in the anterior section of the corneal stroma has halted the progression of Keratoconus. The ultimate goal is to avoid corneal transplants and permit good quality vision with either eye glasses or contact lenses.

These studies have also demonstrated that the earlier this surgery is performed, the better the long term results are. Currently, there are studies being performed in the US and there is a great anticipation that this cross linking therapy will be the answer to a visually debilitating condition.

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