I had LASIK done on November 14, 2019 at Kelly Vision Center in Manhattan, NY. I will summarize some of my research from before the procedure, and how the eyes have healed post-procedure.

Some topics I will touch:

  • Motivation
  • Pre-procedure research
    • LASIK vs. PRK, potential complications, tradeoffs, Lasers (!) and why I chose Kelly Vision.
  • Procedure
  • Post-procedure healing

Disclaimer: This is just my research, and not any sort of medical advice.

References: Are at the bottom, and cited as [X.N]

Motivation

I have been thinking about getting laser assisted corrective surgery for more than a decade. Every few years, I would get my candidacy evaluated. I was always considered a good candidate for both LASIK and PRK. Around 2016, after moving to New York, my contact lenses started to feel more and more uncomfortable, and so, I started thinking about actually getting the surgery done.

My prescription was around -7.00 D spherical and -3.00 cylindrical — So, pretty high myopia and astigmatism. I had been on glasses for 17 years, and contact lenses for 12 years.

I visited Dr. Kelly to get my eyes evaluated and he said that I was a candidate, answered a large number of questions I had, and mentioned that due to the high astigmatism, there was a chance that I would need a touch up 3 months after the procedure. It was good to be aware of this as I made my decision.

Pre-procedure research

Considering this was a surgery of the eyes, I was quite apprehensive and wanted to understand the procedure, side effects and outcomes as clearly as I could. Here are some of the questions I was thinking about:

LASIK vs. PRK

This was the most difficult question to answer. First, some background. There are two relevant parts of the cornea / eye to consider:

  • The corneal epithelial (and Bowman’s membrane?)
    • Newer tissue
    • Outer, protective layer
    • Regenerates
  • The corneal storma
    • Older tissue (laid down early in life)
    • Closer to the eye
    • Does not regenerate - so, if you reshape it, it will stay forever.

Corneal epithelial layer lies on top of corneal stroma layer.

The goal is to reshape the corneal stroma by vaporizing (ablation) parts of it using a laser (excimer).

But to get to the stroma, we have to go through the epithelial in some way.

There are two ways to get through the epithelial to reach the stroma:

  • Vaporize the epithelial. Take it out, throw it away. It will regrow. This is PRK.
  • Make a cut so that it can open up like a flap. After the procedure, replace it back. The epithelial will regrow a bit around the boundary of the flap, securing it. This is LASIK.

So –

  PRK LASIK
Epithelial layer Doesn’t have a flap made in the epithelial – because it removes sections of it completely. Retains most of the epithelial – because a flap is made and pulled to the side to reach the stroma
  With time, the epithelial layer will regrow. As you can imagine, a lot of tissue has to regrow. A small amount of regrowing will occur around the flap’s edges. A lot less to regrow than in the case of PRK.
Complications Regressions in acuity due to regrowth irregularity, corneal thickening, thinning, etc [C.1] Epithelial ingrowth, flap creation, flap setting post-LASIK [C.2]
Advantage No flap related complications Faster healing, reducing risk of regrowth irregularities
Healing process 6 to 12 to 24 months 24 hours to few weeks

Complications and Tradeoffs

LASIK and PRK both have potential complications. Some complications are common to both, and some are specific to them. My general mentality was to be aware of the complications and side effects, and understand how they could be managed if they did occur.

Common to laser based surgeries:

  • Dry eyes
  • Visual acuity impacting: glares, halos, diplopia (double vision), incorrect correction (under/over), new astigmatism
  • Vision loss (!!) (very rare, almost impossible unless there was a surgical issue or post-surgery infection)

LASIK and PRK have different incidence probabilities for those common complications, but they are pretty close to each other. So, it is worth knowing about these regardless of LASIK/PRK.

PRK specific complications:

  • Epithelial regrowth issues (maybe unevenness?)
  • Corneal thickening / thinning during the regrowth (could cause regression even 5 years out [C.3])
    • Thickening many years out specifically in PRK due to activated keratocytes [C.1] [C.3]
    • This is unique in PRK due to the complexity in the epithelial regrowth.
  • Not sure how manageable these complications are. Can they be corrected as they are detected? I am not sure.

LASIK specific complications:

  • Mostly around the flap creation, flap healing and long term flap stability
  • Surgical complications can arise during flap creation
    • Physical blades were used in the past (microkeratome).
    • The new femtosecond laser flap creation greatly reduces flap creation issues.
    • In the vast majority of cases, the procedure can merely be stopped, and retried 3 months later [C.2]
  • Epithelial ingrowth
    • Can be detected in post-procedure followups.
    • Can be corrected post procedure by lifting the flap and cleaning [C.2]
  • Long term flap stability
    • In seemingly rare occasions, the flap can have issues multiple years out [C.4] leading to flap amputation, which can still result in good vision long term.
    • Femtosecond assisted LASIK results in much better long term flap stability. Blunt trauma is not considered a risk factor and atheletes are allowed to have it [C.5].
      • As are Astronauts [C.6].
  • Femtosecond specific complication
    • Rainbow effect [C.7]. It seems to be temporary.

My reasoning

I decided to go with LASIK because of a few reasons:

  • It seemed like the long term visual acuity between PRK and LASIK was generally the same.
    • But some studies gave an edge to Femtosecond assisted LASIK over PRK [D.1] [D.2], especially in the case of astigmatism.
      • Maybe PRK is not as effective as LASIK due to irregularities in regrowth?
      • Femtosecond makes smaller flaps compared to microkeratome. Maybe this helps predictable procedures?
      • Astronauts [C.6] are allowed to get FAL, so seems like it should be fine.
  • The large amount of tissue regrowth in PRK was concerning
    • It would lead to a much longer recovery period. In some cases, it seems like the regrowth would keep going on for years.
      • Quick recovery in FAL, less intrusive on daily life.
    • The predictability of the visual acuity seemed to be much lower than that of FAL.
      • Less regrowth needed in LASIK, more predictable outcome.
    • Management of complications seemed to be unclear (how would you even control the regrowth years out?)
  • Complications arising from flaps made with Femtosecond laser seemed to be manageable (especially compared to mechanically made ones)
    • Complications seemed rare, and if they happened, it seemed like managing them was more straightforward, even years out.
  • FAL seemed to be better in the case of high myopia and high astigmatism (which is what I have)

Lasers!

Modern LASIK uses two lasers:

  • Femtosecond: To make the flap in the epithelial
    • In the olden days and rarely today, a physical blade is used.
    • These days, a laser is used to separate a layer of tissue in the epithelial, which can then be pulled back.
    • The pattern created on the back of the flap can lead to the temporary rainbow effect with some versions of femtosecond [C.7]
  • Excimer: To abalate (vaporize) the stroma
    • WaveLight: Newer system
    • VSX
    • Both are equally good, with a very slight edge to WaveLight, especially with astigmatism [D.4]

LASIK center

I decided to ultimately go with Dr. James Kelly.

He had among the highest reviews in the NYC area. After meeting him, I immediately felt comfortable in discussing my concerns, options, etc. He was kind, patient but also straight forward, which is what I was looking for. Additionally, he has thousands of procedures under his belt, which was an important consideration for me. I liked how much attention he gave to my eyes and how patient he was with all of my questions and concerns. An example of this patience is that it took me 3 years from the first time I saw Dr. Kelly to actually getting the procedure done; and he was always happy to answer any questions and concerns I had. One unexpected benefit of this was that he ended up having 3 years of data on my eyes. This would reduce the unpredictability in outcome. It was a small bonus that he used the WaveLight excimer instead of the VSX (although I was not actively seeking out a WaveLight over VSX).

Procedure

The actual procedure took place on November 14 2019. My Mom and Dad had come in from Toronto to be with me for the procedure. About 4 weeks before the procedure, I stopped wearing my toric contact lenses and started wearing my glasses. I also cut out coffee to minimize eye dryness. I had already seen a few videos of the procedure to understand the full process (I don’t necessarily recommend this!).

Before the surgery, I picked up my prescription eye drops and took them along with me on the day of the surgery:

  1. Prednisolone: Anti-inflammatory
  2. Ofloxacin Ophthalmic: Anti-bacterial

After arriving with my parents (you need to have someone with you), I filled out some paperwork and paid for the surgery (I went with a lifetime guarantee). I was then given a Valium and then walked to the operating room.

The procedure itself was very quick.

  1. Eyes were cleaned and numbed (You are awake during the procedure)
  2. Flap creation: I would say that this was relatively them ore uncomfortable part of the process (but very manageable). There is about a 10 to 15 second period in which the femtosecond laser is brought right on top of the eye
  3. Excimer: The newly created flap was pulled back and the excimer was used for the abalation. This step was not uncomfortable. The only weird thing here is that you can smell the burnt tissue. It has been described as burnt hair.
  4. After both the eyes were done, I could see (!) through my watering eyes. I was taking for a quick post-op check, at which point, Dr. Kelly added collagen tear duct plugs.
  5. My parents then helped me get back to the apartment. My eyes were very sensitive to light and all I wanted to do was go to sleep, which I promptly did.

Post-procedure healing

  • Few hours after procedure

    After waking up, I could see without the need for any glasses(!). Based on some rudimentary tests at home, I seemed to have 20/20, which was quite miraculous. My eyes were sensitive to light. I immediately noticed halo effect, which was quite pronounced. And I saw a slight rainbow effect. Eyes were not that dry (perhaps thanks to the tear duct plugs)

  • Next 24 hours

    Kept up with my eye drop schedule. Eyes were a little dry but not as bad as I was expecting at all. Eyes were quite “normal”. The halo effect and rainbow effect seemed to get a little better.

  • First followup 32 hours post op

    Healing was going fine. Tested 20/15 minus a few letters.

    The 20/20 line was relatively easy to see. The eyes were a bit sensitive to light, and I think with reduced sensitivity, the 20/15 line would have been readable too.

  • Next few weeks

    Finished my dose of the medicated eye drops. Generally the eyes were very stable now. I was taking precautions like keeping them lubricated (they help with the healing process) and using blue light filter glasses to reduce the strain on the eyes. I generally kept hydration levels up.

    The halo effect seems to have reduced, although I do notice a bit more of the rainbow effect, more in one eye than the other. I called the Dr.’s office about this and they said it was perfectly normal.

  • Three week follow up Tested 20/15 minus 1 or 2 characters.

    Healing is going well

    And most importantly, it looks like both the myopia and astigmatism (!) are completely gone. As mentioned above, I was concerned about potential touch ups to correct any residual astigmatism.

    Dr. Kelly mentioned that the halo and rainbow effects are normal and they will subside over time.


Resources

R.1 : https://eyewiki.aao.org/Main_Page

C.1 : Corneal Regeneration After Photorefractive Keratectomy: A Review

C.2: LASIK complications

C.3: Five years results of PRK for myopia. Note: This is from 1997. It suggests that patients with large pre-operative myopia could see regression even 5 years out with PRK.

C.4: Long-term Outcomes of Flap Amputation After LASIK Note: Seven patients present with issues with the flap over the course of 15 years at this institute.

C.5: LVC: No Longer Out of Bounds for Athletes

C.6: Laser refractive surgery in the United States Navy.

C.7: High incidence of rainbow glare after femtosecond laser assisted-LASIK using the upgraded FS200 femtosecond laser

D.1: Two-year results of femtosecond assisted LASIK versus PRK for different severity of astigmatism

D.2: A Comparison of Visual Outcomes and Patient Satisfaction Between PRK and Femtosecond LASIK Note the conclusion: Our study shows superior visual outcomes in patients undergoing FAL (Femtosecond LASIK). However, we found a higher satisfaction rate in those that underwent PRK, perhaps due to the higher cost of FAL.

D.3: A prospective, randomized, fellow eye comparison of WaveLight® Allegretto Wave® Eye-Q versus VISX CustomVue™ STAR S4 IR™ in laser in situ keratomileusis (LASIK): analysis of visual outcomes and higher order aberrations