Corneal Crosslinking offers a solution for slowing or halting the progression of keratoconus. For patients who have keratoconus, crosslinking provides an attractive and minimally invasive tactical approach to slow the disease. At Eye Care Center, Dr. Belinda Dobson examines the cornea and determines if one is a candidate for crosslinking. If we determine corneal collagen crosslinking is an option for the management of keratoconus, we perform the pre-operative examination and carefully work with Dr. Slade’s office to orchestrate the treatment phase.
Purpose:
Corneal Crosslinking (CXL) is an investigational treatment for Keratoconus patients and Post Lasik Ectasia patients that experience corneal thinning after Refractive Surgery. This trial is studying if this one-time treatment will strengthen the cornea so that the progression of Keratoconus and Corneal Ectasia is slowed or stopped.
Background:
Corneal Collagen Crosslinking (CXL) has been proven in studies outside of the US to strengthen a weakened corneal structure, as in keratoconus. CXL is currently in US Food and Drug Administration (FDA) clinical trials to seek FDA approval.
Keratoconus/Effects:
The cornea is the clear membrane that covers the colored part of the eye and pupil. The cornea is the “window” of the eye and is the most powerful lens in the eye as well. Keratoconus is a corneal disease that causes structural changes within the cornea causing the cornea to thin and bulge outward into a steeper, irregular, more conical shape than its normal gradual curve. Keratoconus can cause substantial visual loss of vision, image distortion, streaking of lights, sensitivity to light, and multiple images, etc.
Keratoconus affects about one person in a thousand, and yet the exact cause of it is uncertain. It has been associated with genetic factors and linked to detrimental abnormal enzyme activity in the cornea; however, the findings are still inconclusive. Many patients with keratoconus may be treated with corrective lenses, glasses, contact lenses, intrastromal corneal ring segments, and as a last resort, corneal transplantation. In order to stabilize the cornea, keep the keratoconus from progressing and even avoid having to have a corneal transplant, many patients now have chosen to travel around the world to have corneal collagen crosslinking, also known as "CXL."
Goal:
Crosslinking (CXL) has been shown to increase the number of corneal crosslinks within the cornea. These links are like the natural anchors in the cornea and are responsible for preventing the cornea from bulging outwards and becoming steep and irregular. The goals of crosslinking are to stop the progression of keratoconus, decrease the severity of the corneal bulging, and allow the patient to continue or resume contact lens wear. By decreasing the severity of the corneal bulging, doctors are better able to fit the patient for contact lenses.
Study Parameters:
You may be eligible for this study if you are 12 years of age or older and have been diagnosed with Keratoconus or diagnosed with Corneal Ectasia after refractive surgery (e.g. LASIK, PRK). There are specific inclusion and exclusion criteria that patients must meet in order to be considered participants in the clinical trial. We will be happy to discuss these with you.
Procedure:
The crosslinking treatment is an outpatient procedure performed in the surgical laser suite using numbing eye drops. During this study, the surgeon uses an ultraviolet-A illumination device (UVA light treatment), called the KXL system in combination with VibeX (vitamin B2) eye drops to treat the cornea (front of the eye). First, in the Epithelial Off procedure, the outer layer of the cornea, the epithelium, is prepared for the procedure. If a patient is having the Epithelial On procedure, this step is skipped. Next, vitamin B2 (riboflavin) eye drops are instilled in the eye and the patient is asked to look at an ultraviolet light while lying comfortably in a reclining chair. The entire procedure generally takes only a few minutes. The patient’s eyes are numbed through the use of anesthetic drops.
After treatment:
Post operatively, most patients start to notice the effects in their vision 4-8 weeks after the traditional (epithelial-off) procedure and the final effects usually take 3-6 months. Every patient is different, visual results may differ.
If you are interested in learning more about CXL or keratoconus, please call us at (979) 779-9000 and ask for Madeline.
Please visit the National Keratoconus Foundation's website to see all the approved CXL sites in the United States.
