Corneal Cross-linking (CXL)

Corneal Cross Linking (CXL)

Corneal cross-linking (CXL) is an in-office eye procedure that strengthens the cornea if it’s been weakened by keratoconus, other corneal disease, or (rarely) a complication of LASIK surgery. Alternative and brand names for the procedure include corneal crosslinking, corneal collagen crosslinking, C3-R, CCL and KXL.

The cornea is the clear, outer layer of your eye. The middle or stromal layer is the thickest part of the cornea. It has mostly water and a protein called collagen. Collagen makes the cornea strong and flexible. It also helps the cornea keep its round, regular shape. This healthy cornea focuses light so you can see clearly. 

Some diseases change the middle layer of the cornea. The cornea gets thinner and weaker. This thin cornea bulges into an irregular, cone shape. Your vision may be blurry, and your eyes may be bothered by bright lights. The cornea disease may get worse over time. The medical name for this is corneal ectasia, and there are two types. One type is keratoconus. Older children, teenagers, and young adults may get this and it tends to progress over time often stabilizing in the late 30’s. However it can stabilize earlier and progress later. The other type starts after eye surgery such as LASIK (post-refractive ectasia). 

Corneal cross-linking (CXL) can help make the middle layer stronger. 

CXL is fully covered by MSP for keratoconus. For post refractive ectasia after Lasik CXL is not covered and is completed at an additional cost to the patient. Typically one eye is treated at a time and six weeks later the 2nd eye is treated if needed.

There are 3 steps to CXL. 1) Dr.Bujak will numb your eye with drops and then gently remove part of the outer layer of your cornea termed the epithelium. 2) Special vitamin eye drops (riboflavin) will be administered to your eye over 30 minutes. 3)  a special ultra-violet (UV) light will be shined on your eye for another 12 to 15 minutes while drops are instilled. The vitamin eye drops and UV light work together to make the collagen in the cornea stronger. The cornea becomes stiffer and usually stops bulging out, thus stopping the disease from progressing. 

The goal of CXL is to stop the cornea from getting thinner, weaker, and more irregular in shape. But CXL cannot make your cornea normal again. CXL will likely keep your vision from getting worse, but a small percentage of patients may still progress (about  5%). Sometimes, your vision may even improve but the improvement is small. You will likely still need to wear glasses or hard contact lenses for near or far vision. These are ideally fitted 3 months after the treatment.

Additional options

Some patients may benefit from focal laser or the implantation of ring segments into the cornea at the time of CXL. These procedures aim to reshape the irregular cornea to improve vision. Dr.Bujak will discuss these options with you in the office if you are a candidate. 

Post-operative course

Although the procedure itself is not painful patients typically have significant discomfort on the day of surgery. This greatly improves day by day, usually lasting one week and rarely longer. Although each patient is different, most patients need pain medications only on the first day of surgery. Vision is significantly blurred for the first few weeks but usually recovers within 1 to 3 months. Patients typically have dry eye for 3 to 6 months after the surgery and will require eye drops. For the first month we ask patients to reduce reading and computer work.