Corneal Crosslinking (CXL)
UPDATE: We have completed enrollment!
Slade & Baker Vision Center was the first site in Texas to do corneal cross linking as part of a clinical trial. We offer screening evaluations, at no charge, for patients with ectasia and or KERATOCONUS to find out their options.
Update: There is now an FDA approved form of corneal crosslinking.
Investigator: Dr. Stephen Slade
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.
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.
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.”
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.
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.
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.
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.
Corneal Crosslinking (CXL) FAQs
How effective is Corneal Crosslinking?
There are different types of corneal crosslinking as technology develops. Generally, however, many studies show that CXL can prevent further vision loss in over 95% of patients. Some patients even have slightly better vision afterward, generally due to less extreme glasses prescriptions or better fitting contact lenses.
What’s the difference between a corneal transplant and corneal crosslinking?
A corneal transplant involves removing the clear front windshield of the eye (cornea) and sewing another person’s donated cornea into place.
Corneal crosslinking, however, is a process of using riboflavin (vitamin B2) and UV light to help stiffen and strengthen a weak cornea, with the goal of stopping the progressive weakness than can lead to requiring a corneal transplant.
Will I need to wear glasses after corneal crosslinking?
In general, corneal crosslinking is not considered a vision correction procedure. It is considered a medical strengthening procedure. Expect to still need glasses or contacts afterward. But many patients find that they work a little better or fit better. There are experimental protocols for combining vision correction with crosslinking, and we are happy to discuss these.
When can I return to my active lifestyle?
Most people return to their normal activities within 2 to 7 days.
Will I need to continue to wear contact lenses and how long after the surgery can I wear
Most patients can resume their contact lenses about a week after surgery, after clearance from the doctor.