Park Avenue SafeSight and Dr. Emil Chynn are one of the first centers/surgeons in New York City to offer collagen cross-linking (CXL) as a treatment for corneal warpage, ectasia, and/or keratoconus (KC), which are all reasons that people develop irregular astigmatism, don’t see well, but can’t get LASIK. Sometimes, these conditions can even be caused by LASIK.

Dr. Chynn is also a close colleague with the doctor who has presented and published a lectured more about CXL than any other doctor in the world, since they both trained at Harvard. This doctor works in Athens, and his “Athens protocol” is designed to combine CXL with PRK to treat patients with ectasia simultaneously with CXL to stabilize and strengthen their cornea, and PRK to eliminate their eyeglass prescription.
At the ASCRS meeting in San Francisco in 2013, Dr. Chynn and his Refractive Fellow met with many manufacturers and doctors performing CXL in the US, including with representatives of ASCRS. The summary conclusion was that there were already 300-400 doctors across the US performing CXL already, so if Dr. Chynn had the patient demand and experience already, he (and his patients) should feel very comfortable performing CXL. So the decision was made that Park Avenue SafeSight would become the 3rd center in NYC to offer CXL.

CXL is approved by FDA and is proven to be effective!

CXL is very safe, and the most common “complication” is that it doesn’t work, meaning it doesn’t stabilize the cornea, and the warping or ectasia or astigmatism (and vision) does not stabilize, and continues to worsen. However, this outcome is the same as if the procedure was not performed, so it’s not really seen as a “complication.” Especially because in this case, the CXL procedure can be performed again, until it works (we would only charge cost and not make any profit on the retreatment).

Rarely, true complications do happen, which include haze or scarring which can decrease vision, or endothelial decompensation, which would require a corneal transplant. This last complication, while serious, must be taken into context, as many of these patients would have wound up needing a transplant anyway, if CXL had not been attempted (since the natural history of KC or other similar conditions like pellucid marginal degeneration is progression over decades, eventually necessitating a transplant).

CXL is a very simple, in-office procedure, which involves dropping a special solution of riboflavin (a B vitamin) on your cornea for 30 minutes, followed by 10-30 minutes of UV light (of a similar intensity and wavelength as those blue lights you see in a deli that they use to sterilize surfaces). The procedure is totally painless.

Results are noticeable within a week, with most of the effect by 1 month. A third of patients have such dramatic improvement that they notice greatly improved vision due to the CXL procedure making their protruding flatter, which is not really the purpose of CXL, as that is really just to strengthen the cornea so the progression of warpage is arrested. One third have mild visual improvement, and also arresting of progression. One third see no visual improvement, and a pretty good arrest of progression, although some of these patients may still progress enough to warrant a second CXL procedure.

In summary, CXL is an exciting procedure that yields very good results with very little downside risk, has been approved in Europe for over a decade, and performed successfully and safely on tens of thousands of patients all over the world. Dr. Chynn and PAL are pleased to be the 3rd surgeon/center in NYC to offer CXL in NYC!

If you have one of these conditions and think you may benefit from CXL, just call our center at 212-741-8628 and make an appointment for a second opinion, billed to your medical (not vision) insurance for the consultation (you may have a small copay). Please fax us all your eye records before your visit to (212) 741-2390 so we can make your chart and show them to Dr. Chynn for review before you come in.

Dr. Chynn and Park Avenue SafeSight remain at the forefront of laser vision correction, refractive surgery, and corneal research in NYC, with the largest Refractive Surgery Fellowship Program in the US–we hope you appreciate our efforts to conduct and present research, and understand the benefits of going to an academic center such as ours for your advanced visual care needs!


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