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Cross-linking (CXL) in New York City

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Effective & Safe Treatment for Keratoconus in New York, NY

We are proud to offer collagen cross-linking (CXL) as a treatment for keratoconus and other corneal disorders that lead to irregular astigmatism. During his education at Harvard, Dr. Emil Chynn trained with the physician who has presented and published most extensively on CXL in the world.

Now, after attending additional conferences and seminars on CXL, Dr. Chynn specializes in this revolutionary procedure and performs it at his New York City office. Park Avenue LASEK has the distinction of being one of the very first eye care clinics in New York City to provide CXL.

Dr. Chynn/Park Avenue LASEK/CXL

Dr. Chynn and Park Avenue LASEK have been performing CXL under IRB (Institutional Review Board) supervision for several years. We have more years of experience than almost every other center, private or hospital-based/university, and more patients treated, as well.


Corneal crosslinking (CXL) was developed in 1998 by Theo Seiler, MD (whom Dr. Chynn knows) and has been shown in numerous clinical trials to strengthen the cornea to treat conditions such as:

  • Keratoconus (KC)
  • Pellucid Marginal Degeneration (PMD)
  • Ectasia after LASIK.

Riboflavin, a form of vitamin-B2, is applied to the cornea in the form of drops, followed by treatment with ultraviolet A (UV-A) light, which adds crosslinks to the cornea collagen, much like rebar is added to concrete to make it stronger. This safe treatment, which has been recently approved by the FDA, so medical insurance is starting to cover it, can slow or even stop the progression of keratoconus, PMD, or ectasia after the cutting LASIK procedure (ectasia after PRK/LASEK is much less common because those procedures are non-cutting).

Schedule a FREE Corneal Crosslinking Consultation

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Looking for a Corneal Cross-linking near you?

CXL is FDA-approved, and it has demonstrated a high degree of effectiveness in treating keratoconus. This treatment aims to strengthen the cornea in order to stop the progression of corneal warpage. However, some people see even more dramatic improvements in their vision, due to the way their cornea flattens after CXL (even though this is not the real purpose of cross-linking!).

How is the cross-linking procedure done?

The simple procedure is done in-office and it is entirely painless.

  1. Dr. Chynn will drop a special solution of riboflavin (B-vitamin) on your cornea for 30 minutes.
  2. Next, your eyes will be exposed to 10-30 minutes of UV light. The intensity of these light waves are similar to the sterilizing blue lights you’ve seen at the deli counter.
  3. Wait for results! Typically, our New York City eye care patients notice results within one week, and most of the effects are experienced within one month.

Two Basic Types Of Corneal Crosslinking

Epithelium off, which means the thin layer covering the eye’s surface is removed, allowing for faster penetration with liquid riboflavin, and more effective crosslinking. This is the type we perform, and are the best at getting the epithelium to grow back quickly without pain or scarring, because we perform nearly 1,000 LASEKs per year, where we also remove the epithelium and need it to grown back rapidly, so have more experience with this than any other center in the US!

Transepithelial corneal crosslinking (epithelium on) is where the corneal epithelial surface is left intact, which requires a longer riboflavin loading time.  Many published studies have shown this method to be less effective than epi-off, and NO study has shown epi-on to be MORE effective--leading to the conclusion that epi-on is LESS effective than epi-off.  So why leave the epithelium on, and have your CXL maybe not work--rather than get epi-off and have it be EFFECTIVE at a center that is EXPERIENCED at getting your epithelium to grow back quickly?

Are there risks or complications involved with CXL?

girl blue eyes 1280x853CXL as a treatment for keratoconus is a promising procedure that leads to very positive results – with minimal risks involved. It was approved for use in Europe over 10 years ago, and it has been performed safely and successfully on tens of thousands of patients worldwide.

Regarding complications, the most common complaint is that CXL doesn’t stabilize the cornea and the patient’s condition continues to deteriorate. Simply put, CXL doesn’t work. However, this is the same outcome as if the procedure was never done – so it isn’t much of a “complication.”

Very rarely, people experience scarring or haze as a complication, or they have endothelial decompensation that requires a corneal transplant to correct it. Of course, had many of these same patients not undergone CXL, they may have eventually needed a corneal transplant to treat their keratoconus.

Am I a candidate for cross-linking in New York City?

Dr. Chynn, our keratoconus specialist, is at the forefront of advanced treatments for many ocular conditions. If you have keratoconus or another corneal disorder and would like to learn more about cross-linking, contact our New York City eye care clinic. We will assess your eyes and determine if you are a good candidate for advanced collagen cross-linking.

Best Candidates For Corneal Crosslinking

  • Patients with Corneal Ectactic Disorders (Keratoconus or Pellucid Marginal Degeneration)
  • Patients with ectasia/regression/need a reoperation after LASIK
  • Patients with high prescriptions or thin corneas considering cutting vision correction procedures such as LASIK might eventually be pre-treated with corneal crosslinking to strengthen the eye’s surface beforehand (this is known as the “Athens Protocol” and was developed by John Kannelopoulos, MD, who trained at Harvard with Dr. Chynn).

What Can You Expect After A Corneal Crosslinking Procedure?

  • Improved Visual Acuity
  • Decreased visual fluctuations
  • Prevent need for corneal transplant after complicated/defective LASIK

What Should I Do if I’m Interested in CXL or Think I Might Need It?

  • Call or email our office to set up a CXL Consultation
  • The cost is $300 or FREE if you have valid medical (not vision) insurance
  • The cost of your CXL treatment may also be covered
  • Don’t wait until your condition gets worse--act now!

No other laser vision correction surgeon in New York….

No other laser vision correction surgeon in New York....

...offers you the opportunity to have a Free Remote Consultation with the surgeon! Ask Dr. Chynn your main question or concern, and will answer, personally, within 2 business days!

Unsure whether you're a good candidate because of a lot of astigmatism? Large pupils? Dry eyes? Maybe you were rejected by LASIK surgeons due to a “thin cornea” or high prescription.

Take advantage of this incredible opportunity to find out if LASEK is an option for you from Dr. Chynn, our famous, cornea fellowship-trained, Columbia & Harvard graduate who’s in MENSA & was the 1st eye surgeon in NY, NJ, CT & PA to get LASIK, & has performed 1,000 PRKs, 5,000 LASIKs, 10,000 LASEKs, and 5,000 epiLASEKs

But please be considerate. Dr. Chynn gets paid $1,000/hour as a consultant for expert networks & expert witness, so please limit yourself to your most pressing question or concern, as he’s doing this for free on a trial basis to help interested patients.

Please include the information below in your email so Dr. Chynn can answer your question specifically.

Approximate prescription (if known):
Occupation (the more specific the better):
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No other laser vision correction surgeon in New York….

This Form Will Be ANSWERED by Dr. Chynn HIMSELF - NOT a Salesperson!

Dr. Chynn graduated from Dartmouth + Columbia + Harvard + Emory + NYU and has been featured on CNN, ABC, NBC, CBS, Discovery Channel & in the NY Times & Wall St. Journal

He's performed 1,000 PRKs, 5,000 LASIKs, 15,000 LASEKs - more than any surgeon in the US

He got LASIK in his right eye & LASEK in his left eye, so is UNIQUELY qualified to tell you the +/-'s of BOTH procedures – from BOTH a Surgeon's & Patient's point-of-view!


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