Corneal Collagen Cross Linking (CXL)

Have you ever been told by an eyecare professional that you are not a good candidate for laser corrective surgery? You may have a disorder of the cornea that can be treated with brand new corneal collagen cross-linking technology. Consultation with Dr. Rush can help determine the most appropriate medical treatment for eyes that cannot have laser corrective surgery due to an underlying disease or high astigmatism.

The old CXL technology by Avedro is not the only option. The latest CXL technology is now available near you. Your corneal evaluation and advanced CXL treatment can be completed in just one visit to Dr. Rush’s clinic. Your local optometrist is able to provide all continuing care and fit you with glasses and contact lenses after the treatment.

What is Corneal Collagen Cross-Linking?

Corneal Collagen Cross-Linking, or CXL, is used to increase the rigidity and strengthen the surface of the eye by inducing additional “cross-links” within the structural collagen fibers in the cornea. By using ultraviolet light and a photosensitizer (riboflavin/vitamin B2), CXL can help to slow, stabilize and even partially reverse the progression of disease conditions of the cornea such as keratoconus or ectasia.

What can CXL be used for?

CXL can be used for Keratoconus, Pellucid Marginal Degeneration, and Ectasia after previous laser corrective surgery. These are all disease conditions where treatment with a LASIK procedure is not an option.

What is Keratoconus?

The cornea is the front, round-shaped and clear window on the surface of your eye. It focuses light onto the retinal nerve tissue in the back of the eye. Keratoconus is a disorder in which the cornea may progressively thin and bulge into a cone-like shape. In the setting of keratoconus, the abnormal shape and irregular astigmatism of the cornea may result in decreased ability of the eye to focus light which causes distortion in the vision. Progressive vision loss from keratoconus may begin to develop in the early teenage years.

What does CXL do?

While this procedure does not cure keratoconus, it is effective to stop progression of the disease and help prevent further damage to the cornea. In many cases, it can prevent the need for a corneal transplant when the disease is detected and treated at an early stage. CXL does not eliminate nearsightedness, farsightedness, or astigmatism so that glasses and/or contact lenses will still be necessary after treatment. However, newer technology where CXL is used in combination with laser treatments

What is the CXL process?

During the treatment, riboflavin (vitamin B2) liquid eye drops will be applied to the surface of the eye to help saturate the cornea. Afterwards, an ultraviolet light source (UV-A at 365 nanometers) is applied to the eye which activates the riboflavin and increases the strength of the cornea by binding adjacent collagen fibers with additional bridging crosslinks. The entire procedure usually takes under one hour to complete.

Who should have CXL and when should you have it?

Anyone diagnosed with keratoconus (or any similar “corneal ectasia” disease) should be evaluated by a corneal specialist to determine if CXL is an appropriate treatment for you. The evaluation should occur immediately as keratoconus often times will develop at a young age and progress over time, sometimes very rapidly. The damage that occurs cannot be cured or fully reversed. It is extremely beneficial to get CXL done at an early age to help preserve vision and prevent the need for a more invasive surgery with a corneal transplant.

How has CXL technology changed?

CXL has been successfully used since the late 1990’s. It was extensively researched in Europe throughout the early 2000’s where it has been widely adopted and routinely performed there for over 20 years. Since that time, it has slowly gained worldwide acceptance as massive amounts of data from CXL research have demonstrated its incredible efficacy for halting progression of keratoconus and other corneal ectasia disorders. However, in the United States, the slower Food and Drug Administration (FDA) approval process did not allow for its widespread use here until 2016 with the approval of Avedro’s KXL system and Photrexa riboflavin formulations (by Glaukos). This system uses the same technology that was originally used in the late 1990’s. But like almost everything in the medical field, the CXL technology has advanced dramatically over the last 20 years. More cutting-edge methods combine the CXL procedure with Contoura Vision topography-guided WaveLight laser technology (link to our Contoura landing page), the same technology used for advanced LASIK procedures. This customized topography-guided treatment uses the excimer laser to flatten the cornea and reduce irregular astigmatism associated with keratoconus immediately prior to performing CXL. Successful use of this newly-developed, combined procedure is not only effective at stabilizing the diseased cornea but may also improve vision and the shape of the cornea (https://www.ncbi.nlm.nih.gov/pubmed/30410923). Other more advanced techniques include accelerated CXL treatments that reduce the total treatment time (https://www.ncbi.nlm.nih.gov/pubmed/32126042). The latest medical devices for performing CXL have advanced features such as the automated EyeTracker and the accelerated radiation modes (http://www.peschketrade.com/products/peschke-cxl/).

How can you benefit from new CXL innovations today without leaving the US?

Dr. Rush has always been at the forefront in the development and adoption of CXL in the United States. He has been performing CXL in clinical trials since 2011, several years prior to the FDA clinical trials began for the Avedro products. His research was published in prominent scientific journals around the same time CXL was first approved by the FDA (https://www.ncbi.nlm.nih.gov/pubmed/27388250). Today, keratoconus patients can have access to more advanced CXL technology in the United States through participating in new research studies. Dr. Rush’s FDA-registered and IRB-approved clinical trial is available now to patients that meet enrollment criteria for the study. In order to be in full compliance with federal regulations and for your own safety, it is important to have CXL with only FDA-approved medical devices and riboflavin solutions (by Avedro/Glaukos), or else with FDA-compliant clinical studies that are part of a valid investigational new drug (IND) study. As of the first quarter of 2020, we are the only center in the United States recruiting IND study patients for CXL combined with Contoura Vision topography-guided WaveLight laser treatments (www.clinicaltrials.gov). The Contoura Vision and its imaging capability with the Topolyzer are able to create a custom treatment profile that is specific for the unique shape of your cornea in order to reduce irregular astigmatism associated with the keratoconus. Schedule an appointment to see if you are a good candidate for our IND study with the most advanced CXL technology using accelerated techniques and using the treatment in combination with the customizable Contoura Vision WaveLight EX500 laser.

Will my insurance cover CXL?

Some commercial medical insurance plans will now cover portions of the treatment cost for the older CXL technique that was approved by the FDA in 2016. This is usually of no benefit to our younger patients that may have high-deductible insurance plans. Most of our keratoconus patients that will benefit from treatment are typically 35 years old or younger. Furthermore, enrollment in our research trial offers the latest CXL technology now. The out-of-pocket payment associated with the study will allow for you to have the most advanced procedure available worldwide, right here in the United States. Private insurances do not typically cover costs associated with participation in research trials, but you are still able to file the claim for which it may be partially or even fully reimbursed depending upon the carrier. We are able to give you an estimate of what your insurance will pay for the older CXL technique and what your responsibility will be versus what you will pay for research-associated expenses if you opt for the newer CXL technique through the clinical trial.