Issue 29.16
The cornea is the clear dome-shaped protective front of the eye, responsible for focusing light and producing a good image. The shape and clarity of the cornea is immensely important for precise vision. In some patients, weakening of the cornea can cause it to bulge outward. This change in shape can result in keratoconus, a progressive disease affecting millions of people throughout the world and hundreds of thousands in the United States. Typically starting in the 20’s, this weakening of the cornea can progress over 10-20 years. The cornea changes from a symmetrically round shape to a cone shape, as well as causing it to thin. Tiny fibers within the cornea that hold the shape become weaker, allowing this distortion to progress, and the vision to worsen. Early treatment may consist of simply correcting with glasses, though as the disease progresses, specialized rigid gas permeable contact lenses may be needed. Oftentimes, this thinning and protrusion of the cornea becomes extreme, and may necessitate a corneal transplant. A transplant is the replacement of diseased tissue with healthy tissue.
However, a new non-surgical treatment has recently been approved by the FDA that has been shown to slow or stop the progression of the disease. First introduced in 1998 in Germany, corneal crosslinking has been extensively researched and studied. Since 2006 it has been widely used and accepted in more than 400 clinical centers in Europe. It was first brought to the United States in 2008 and was approved by the FDA in April 2016. Corneal crosslinking utilizes an eye drop containing riboflavin (Vitamin B2) and an ultraviolet light source applied to the cornea over an approximately 30-60 minute period. This increases the molecular bonds between collagen fibers in the cornea, thereby increasing the rigidity and mechanical strength of the corneal tissue. This additional strength stabilizes the cornea allowing it to maintain a more normal shape and resist progressive degeneration.
After corneal crosslinking, many patients are able to maintain good vision with contact lenses or glasses and avoid developing advanced disease which could lead to corneal transplantation. This new treatment may also be beneficial for patients suffering from other forms of corneal instability, such as after laser vision correction with LASIK or PRK, or corneal dystrophies and other degenerative corneal changes.
Dr. Edwards is the only Fellowship trained Cornea Specialist in St. George, Mesquite and Cedar City. This technology is being offered by Dr. Edwards exclusively at Dixie Ophthalmic Specialists at Zion Eye Institute. For more information, call 435-656-2020 or visit our website at Dixieos.com.