Advanced Surface Ablation (ASA)

Recently, there has been a lot of excitement about “Advanced Surface Ablation” as the absolutely safest technique in laser vision correction. But what exactly is ASA?

The term “Advanced Surface Ablation” or ASA was created to distinguish the most modern way to correct vision with a laser without cutting any flap into the eye at all, from a much earlier technique called PRK, or photorefractive keratectomy.

Both PRK and ASA avoid all cutting so are safer than LASIK, “bladeless” LASIK, and SMILE, which all require incisions to be created into the cornea, thereby permanently weakening your eye. PRK and ASA accomplish this by lasering the cornea surface itself, avoiding the need for the surgeon to go deeply into your eye. This is why both PRK and ASA are also known as “surface ablations” — because the laser is removing tissue (“ablating”) from the surface of your cornea, thereby avoiding the need to make cuts into your eye.

PRK was the original laser vision correction (LVC) procedure, so it’s been around since 1995. However, it never became popular because it is very painful (usually requiring the surgeon to give the patient narcotics to make it bearable), and the recovery is very long (meaning you don’t see ok for weeks and don’t see perfectly for months). This is because PRK involves using an Amoilis brush to “sandpaper” off your corneal epithelium, or a “hockey stick” metal instrument to scrape off the skin of your eye. Both of these techniques are very traumatic to your eye and kill literally millions of corneal epithelial cells, which release inflammatory mediators such as cytokines, which trigger the inflammatory cascade, leading to pain, prolonged healing, and in many cases, scarring, which may cause permanent visual loss.

ASA is synonymous with “alcohol-assisted PRK” or LASEK. ASA uses a dilute alcohol solution to delaminate, or gently separate the corneal epithelium from the underlying cornea. The skin is removed in an “en bloc” dissection, as one clean sheet, ideally, and placed on the surgical tray, where again millions of epithelial cells die & release cytokines. But who cares? These inflammatory triggers never touch the cornea, so the inflammatory cascade is never triggered. Thus: no pain or prolonged healing or scarring!

Dr. Chynn helped invent LASEK when he was a Resident at Harvard’s Massachusetts Eye & Ear Infirmary from 1993-1996, where two of his mentors, Juan Carlos Abbad, MD, and Jonathan Talamo, MD, developed this technique (the three of these eye surgeons also published a paper together).

Dr. Chynn has performed more ASA or LASEK procedures than any other eye surgeon in the US–over 20,000! He has preformed more ASA or LASEK procedures than every other eye surgeon in NY, NJ & CT–combined! So if you are in the NY TriState region, and want the safest non-cutting procedure, you’re lucky, because we have patients flying in from CA or FL, or sometimes, even places like London, because they want to go to the most experienced ASA surgeon in the US (and one of the most in the world).

Between 2015-2021, Dr. Chynn also performed about 5,000 epi-LASEK (also known as epi-LASIK) procedures, which is an even more advanced technique, where a plastic separator is used to delaminate the corneal epithelium, avoiding the need for alcohol, which is toxic to the regrowing corneal epithelium. This makes recovery even quicker and approaches the most rapid recovery of a LASIK or SMILE–but with better safety. Dr. Chynn has performed more epi-LASEK (or epi-LASIK) procedures than any other surgeon in the US and was instrumental in moving the entire profession of eye doctors to call the technique epi-LASEK instead of epi-LASIK (because it’s more like a LASEK than a LASIK). 

Epi-LASEK is so safe, that in 2020, Dr. Chynn became the first and only surgeon in the world to perform laser vision correction on himself, to prove to the world that this non-cutting technique is so safe, an experienced surgeon can do it himself! 

In 2022, Dr. Chynn invented the most advanced ASA technique in the world, which he named “vacuum LASEK” in which even the plastic separator is eliminated! He eliminated the plastic separator because rarely (about 1 in 1000 cases) the plastic separator intrudes into the corneal stroma, which can cause irregularities that cannot be eliminated with the laser, leading to visual distortions. In “vacuum LASEK” a gentle vacuum of air is used to allow Dr. Chynn to remove the epithelium, without the need for either alcohol or a plastic separator. 

This is currently the safest procedure to correct your prescription in the world, the safest form of ASA, and has the fastest recovery. So safe that Park Avenue LASEK is now the only laser vision correction center in the US where the operating room is all glass, so each and every procedure is visible by the general public. Like the concept of an “open kitchen” at a very high-end restaurant, this can only be done where quality control is perfect–because your customers are watching the process itself!

Anyone living in the northeastern US can drive or take a train or bus to let Dr. Chynn perform their ASA. Or they can go to a local LASIK surgeon who has performed as many ASA procedures in his or her entire career, as Dr. Chynn performs every year or month. The choice is yours!