Keratoconus (kehr-uh-toh-KOH-nus) is the most common corneal dystrophy that leads to severe visual impairment. It affects 1 in every 2000 people and is 15% more common in individuals with Down syndrome. Although not a common known eye disorder, it is by no means rare, and it is becoming more common due to the use of modern diagnostic equipment.
Keratoconus is a condition in which the normally round, dome-shaped cornea (front window of the eye) thins and becomes distorted and irregular. A cone-like bulge develops, resulting in significant visual distortion. The apex of the cone is usually displaced outwards and downwards and in the line of sight, creating irregular astigmatism.
Keratoconus is typically diagnosed in the late teens or early 20's, although it is occassionally diagnosed in young children as well as people in their 30's or 40's. It us usually slow to progress, taking 10 to 20 years, but sometimes it is very rapidly progressing going to an advanced stage in as short as 6 to 12 months from diagnosis. In our experiences, this seems to be a more common occurrance for individuals with Down syndrome. Also, At this time, there is no known cause, but studies have shown that genes on chromosomes 21, 17 and 13 may play a role. In addition, eye rubbing has been suggested to be a cause as well.
Until recently, there has been no treatment that stopped the progression of Keratoconus and instead the symptoms were treated keratoconus is treated through eyeglasses, hard contact lenses, and a newer treatment, INTACS plastic rings inserted into the mid layer of the cornea to flatten it, changing the shape and location of the cone. Again, these just corrected the distorted vision of Keratoconus patients, but did not stop the progression of the disease.
In 15-20% of the cases, cornea transplant surgery is necessary. When vision can no longer be corrected with contacts or the patient can no longer tolerate the uncomfortable contacts, a cornea transplant is the next option. Cornea transplants are the most common type of solid tissue transplant, and Keratoconus is the major cause of cornea transplantation in the Western world.
Maybe this "treatment" of Keratoconus is changing, so that rather than treat the symptoms (but still have the disease progress), the disease can actually be treated. Approximately 10 years ago, Dr. Theo Seiler developed a procedure called Corneal Cross-linking (CXL).
CXL Procedure
CXL is a procedure that involves administering riboflavin and UVA in carefully selected parameters that strengthen the front layers of the cornea and avoid damage to the back of the eye.
