Collagen Cross-Linking

Collagen Cross-Linking

What is Collagen Cross-Linking?

Corneal Collagen cross-linking is a treatment that uses UV light and vitamin B2 (Riboflavin) to strengthen collagen in the human cornea. Collagen cross-linking is not a cure for keratoconus or corneal ectasia.

The aim of this treatment is to arrest progression of these conditions in attempt to prevent profound loss of vision or the need for a corneal transplant. Collagen Cross-Linking using Avedro KXL system and Photrexa Riboflavin solution is fully FDA approved. ( Other cross-linking systems including CXL and C3R are not FDA approved for use in United States.

How does Collagen Cross-Linking Work?

Cornea collagen cross-linking is approximately an hourlong out-patient procedure. Following application of vitamin B2 eye drops to the cornea, the cornea is exposed to a specific wavelength of UV light. The light interacts with vitamin B2 and cornea collagen fibrils making it less flexible and stronger.

How effective is Collagen-Cross-Linking

Collagen cross-linking has been used in Europe since 1998. It has been a standard of care for keratoconus and corneal ectasia treatment in both Europe and Canada. Avedro Inc. brought this technology to the United States. Dr. Anita Miedziak of the Princeton Eye Group was one of only two surgeons in New Jersey to be involved with the surgical approval process with the FDA. (principal investigator in Phase 3, multi-center, randomized, controlled evaluation to study accelerated corneal collagen cross-linking with KXL System (Avedro) in eyes with keratoconus or corneal ectasia after refractive surgery (

Who is a good candidate for collagen cross-linking?

  • People with mild to moderate keratoconus.
  • People with mild to moderate corneal ectasia.

Who is not a good candidate for collagen cross-linking?

  • People with advanced keratoconus with very thin or very steep corneas
  • People with corneal scaring
  • People with active inflammatory or autoimmune conditions other than keratoectasia (for example rheumatoid arthritis, Sjogren’s syndrome etc.)
  • People with ocular herpes simplex or zoster infections
  • Women who are pregnant or breast-feeding
  • People with history of delayed healing

What are the benefits of collagen cross-linking?

Collagen cross-linking is not designed to cure keratoconus or eliminate glasses or contact lenses. Its purpose is to arrest progression of keratoconus or corneal ectasia and is successful in doing so in 90-95% of cases. In 60-80% of cases, some improvement in vision and/or corneal curvature is also found. In most cases the need for more invasive treatment, namely corneal transplantation surgery, is avoided.

How can I find out if I’m a candidate for collagen cross-linking?

A detailed cornea consultation and corneal advanced imaging is necessary to determine if you have keratoconus or ectasia and if you are a candidate for cross-linking treatment.

Dr. Anita Miedziak, cornea specialist with The Princeton Eye Group was a Principal Investigator in KXL studies and is currently treating and evaluating individuals with progressive keratoconus and corneal ectasia for KXL cross-linking procedure.

If you have keratoconus or corneal ectasia and would like to learn if you are a candidate for cross-linking treatment please contact the Princeton Eye Group and Ms. Kelly Friel and Dawn Fabian (Wills Laser Vision Center Coordinators) at 609 924 9200 or call 609 921 9437 and request a corneal consultation with Dr. Anita Miedziak.

Additional information about cornea collagen cross-linking can be found at:


Back to Corneal Diseases and Treatments