What is Keratoconus?
Keratoconus is an eye condition that affects 1 out of every 2,000 people according to the National Keratoconus Foundation. It is a non-inflammatory condition of the cornea in which there is progressive thinning of the cornea changing it from dome-shaped to cone-shaped. The cornea is the clear windshield of the eye and is responsible for refracting most of the light coming into the eye. Therefore, abnormalities of the cornea can greatly affect the way we see the world.
Keratoconus is not a blinding disorder, but does result in increasing near-sightedness (things far away are out of focus) and irregular astigmatism (things look tilted) that can significantly distort your vision. It is almost always bilateral (affecting both eyes). It is a slowly progressive disorder, taking years to develop, and may halt at any stage from mild to severe.
Signs and Symptoms
During the early stages, the symptoms of keratoconus may be similar to having the need for glasses or contacts. As the disease progresses, the vision deteriorates. Keratoconus will often progress slowly for 10 to 20 years and then suddenly stop. As the condition progresses, the most common symptoms include:
- Increased blurring and distortion of your vision
- Sensitivity to light
- Increased nearsightedness or astigmatism
- Frequent eyeglass prescription changes
- Inability to wear contact lenses
Keratoconus treatment often depends on the severity of the kerataconus symptoms. Contact lenses are the most popular nonsurgical treatment for symptoms related to keratoconus. Contact lenses can provide good vision in early to mid stages of keratoconus by correcting the refractive error, but lens tolerance and good quality vision can be difficult to maintain as the condition progresses.
The first and only cross-linking treatment approved by the U.S. Food and Drug Administration (FDA) for progressive keratoconus, this progressive and sight-threatening eye condition that affects more than 160,000 Americans. Corneal cross-linking—using Avedro’s Photrexa products and KXL System—is used to stiffen corneas that have been weakened by disease.
Corneal cross-linking using Avedro’s Photrexa products and KXL System is a medical procedure that combines the use of ultra-violet (UV) light and riboflavin (vitamin B2) eye drops. The procedure works by creating new corneal collagen cross-links, which results in a shortening and thickening of collagen fibrils that leads to the stiffening the cornea. Cross-linking, which has been performed in Europe since 2003, is considered the standard of care around the world for keratoconus.
Keratoconus can also be treated with Intacs, which are small curved implantable corneal inserts that reshape the cornea and add structural integrity to the cornea. This unique attribute make Intacs an ideal treatment for keratoconus.
The placement of Intacs inserts remodel and reinforce the cornea, eliminating some or all of the irregularities caused by keratoconus. The procedure takes approximately 15 minutes per eye and is performed in office as an outpatient procedure. Follow up visits will be required to monitor the healing process and to evaluate the visual outcomes.
The goal of the Intacs procedure is to provide the keratoconic patient with the ability to achieve improved functional vision with contact lenses or glasses, and, in some cases, without them. They can provide an effective option prior to considering a cornea transplant.
Intacs were originally designed and FDA approved to correct mild nearsightedness, and now Intacs have emerged as a new therapy for treating patients with keratoconus.
When good vision is no longer possible with other treatments, a corneal transplant may be recommended. Corneal transplants are the most commonly performed tissue transplant in the world, with some 48,000 procedures performed in the U.S. every year. The surgery restores eyesight for people who have a damaged cornea from keratoconus, injury, infection or inherited corneal disease.
A corneal transplant is an outpatient procedure that usually takes less than one hour. The diseased cornea is removed and replaced by the donor cornea with an instrument that acts like a cookie cutter (trephine) by making a precise circular cut. The donor cornea, cut to fit, is placed in the opening. Dr Jackson then uses a fine thread to stitch the new cornea into place. The stitches may be removed at a later visit. After the surgery, you will be required to place a plastic shield over your eye to protect it from being inadvertently rubbed or bumped.
While a corneal transplant will relieve the symptoms of keratoconus, it may not provide you with flawless vision. Even after a successful cornea transplant, most keratoconic patients still need glasses or contact lenses for clear vision.