Corneal Cross-Linking (CXL)

Beverly Hills Corneal Cross-Linking

 4th Biennial Asia Cornea Society Meeting

Corneal Cross-Linking Expert,

Ronald N. Gaster, M.D. F.A.C.S.

As a leading ophthalmologist in Beverly Hills and Orange County, California, Dr. Ronald N. Gaster is on the cutting edge of developments in eye surgery and disease.

Dr. Gaster is currently a principal investigator in a clinical trial under an FDA protocol approved by the Western Institutional Review Board (WIRB) studying the overall efficacy of corneal cross-linking (CXL) alone to corneal cross-linking (CXL) plus Intacs for keratoconus or post-LASIK ectasia or pellucid marginal degeneration.

Corneal cross-linking uses riboflavin eye drops combined with ultraviolet light to stiffen and strengthen the corneal fibers and thus halt the progression of the disease process.

Dr. Gaster is also a lead investigator in an FDA clinical trial for corneal cross-linking on adolescents down to age 10. He was interviewed by EyeWorld during the recent American Society of Cataract and Refractive Surgery meeting. Watch his interview below.

Dr. Gaster is interviewed by EyeWorld at the recent American Society of Cataract and Refractive Surgery meeting on Cross-Linking for Adolescents with Progressive Keratoconus

Dr. Gaster has been an invited speaker nationally and internationally on corneal cross-linking, presenting his results at numerous ophthalmology meetings.

He was recently invited to speak at the Jules Stein Eye Institute at UCLA to present his results on corneal cross-linking for Pediatric patients with progressive keratoconus. He also discussed corneal cross-linking and the surgery was videotaped and shown on the Emmy-award winning TV show, “The Doctors.”

What is Keratoconus?

Keratoconus, often referred to as ‘KC’, is an eye condition in which the cornea weakens and thins over time, causing the development of a cone-like bulge and optical irregularity of the cornea. Keratoconus can result in significant visual loss and may lead to corneal transplant in severe cases.

Who is affected by Keratoconus?

A rare condition, keratoconus typically first appears in individuals who are in their late teens or early twenties, and may progress for 10-20 years, and then slow or stabilize. Each eye may be affected differently. Keratoconus is found in both genders and all ethnic groups. While the exact cause of keratoconus is unknown, it is believed that genetics, the environment, and the endocrine system all play a role. Individuals with Down Syndrome are especially affected by keratoconus. Early detection is key in preventing keratoconus from progressing.

 What are the Symptoms?

Many keratoconus patients are unaware they have this rare eye condition. In the early stages of keratoconus, people might experience slight blurring of vision, distortion of vision and increased sensitivity to light.

What is Corneal Ectasia?

Corneal ectasia, also marked by progressive corneal steepening and thinning, is a rare but serious complication that infrequently follows laser vision correction procedures—such as laser-assisted in-situ keratomileusis (LASIK) and photorefractive keratectomy (PRK). It is also associated with worsening vision.

What is Corneal Cross-Linking?

Corneal Cross-linking is a minimally invasive outpatient procedure for the treatment of progressive keratoconus. FDA approved epi-off cross-linking combines the use of prescription eye drops, Photrexa® Viscous, Photrexa®, and ultra-violet A (UVA) light from the KXL® system to create new collagen cross-links and leads to the stiffening and strengthening of the cornea. The goal of the procedure is to stiffen the cornea to slow or prevent further progression of the condition and preserve your vision.

 Types of Cross-Linking:

There are two types of Corneal cross-linking procedures, epi-off and the experimental epi-on. “Epi” refers to epithelium, the outermost layer of the cornea. These procedures are performed to slow the progression and treat keratoconus, not reverse it. In epi-off cross-linking, which is FDA-approved, Dr. Gaster will gently remove the epithelium before applying drops to the eye. In epi-on cross-linking, the epithelium is not removed. Multiple peer-reviewed studies have shown that epi-off cross-linking results in significantly better outcomes than epi-on cross-linking at this time. Therefore, Dr. Gaster recommends epi-off cross-linking for better results.

2 photos of crosslinking procedure

What to expect during a Cross-Linking procedure? 

  • After numbing drops are applied, the epithelium (the thin layer on the surface of the cornea) is gently removed by Dr. Gaster.
  • Photrexa eye drops will be applied to the cornea for at least 30 minutes.
  • Depending on the thickness of your cornea, Photrexa Viscous drops may also be required.
  • Dr. Gaster will then check your cornea for adequate riboflavin saturation of the cornea and corneal thickness.
  • The cornea is then exposed to UV light for 30 minutes while additional Photrexa Viscous drops are applied.
  • A bandage soft contact lens and antibiotic drops are then applied to the eye.

Does Insurance Cover Corneal Cross-Linking?

Insurance coverage for FDA approved cross-linking is now widely available as an increasing number of commercial insurance carriers are recognizing the medical necessity of the procedure. Greater than 95% of the commercially insured population has access to this potentially sight-protecting treatment.

For additional information on insurance coverage, please contact Dr. Gaster’s office to discuss with the billing staff and schedule a consultation with Dr. Gaster.

Corneal Cross-Linking Patient Testimonial

My son was referred to Dr. Gaster after progressively losing his eye sight. From the very first visit, we knew we made the right choice. Dr. Gaster was always willing to answer our many questions as this was all new to us. Their staff just as patient with my many questions and numerous phone calls.

My son has epi-off cross-linking surgery on his right eye. The surgery went very smoothly and Dr. Gaster explained every step to my son who was 21 at the time. From the very beginning, we were advised that there was a possibility of needing a transplant on his left eye that he has not been able to see out of for almost 5 years if not longer.

In March of 2020, my son had a cornea transplant on the left eye. Dr. Gaster explained the process and the procedure in detail. The staff worked with our insurance carrier and handled everything for us. That process also went smoothly.

We had surgery on a Thursday. Everyone at the surgery center were great! Dr. Gaster came out and explained everything to us. We went home so he could begin his recovery. We had an appointment the next day and his eye looked great.

Saturday morning my son’s eye felt like something was itchng. So I called Dr. Gaster and he met us in his office Saturday morning. A stitch had come loose and he took that stitch out. We came back on Monday and the patch was removed. We have followed up with weekly then monthly visits.

My son is doing fabulous! Thanks to Dr. Gaster my son is doing WONDERFUL! We are so very thankful and grateful for the new life Dr. Gaster has given to my son. I would and do recommend Dr. Gaster to anyone that has any issue with their eye!

Kim H., Google Review 2020


Intacs are implantable intra-corneal ring segments (see photo) that can also benefit patients suffering from keratoconus or ectasia by flattening a steep cornea.

Corneal intacs on a finger.

Dr. Gaster uses a Femtosecond Laser to create the channels for insertion of the Intacs segments. Both of these modalities are significantly more effective than orthokeratology or gas permeable hard contact lenses used to try to reshape the cornea. More importantly, by cross-linking early in the disease process, patients may avoid the need for corneal transplantation in the future.

Patients suffering from any of these conditions are encouraged to schedule a consultation with Dr. Ronald N. Gaster to discuss their eligibility.

Dr. Gaster is passionate about the new, effective advancements in the treatment of a variety of ocular diseases and looks forward to improving the ocular health of his patients with these discoveries.