In July of 2011, I had PRK laser eye surgery done. Shortly before, I wrote up a Primer on PRK vs Lasik that the reader may find interesting (TL;DR: Lasik is a dodgy quick-fix, avoid it). Long before signing up for the surgery, long before going under the laser, I did a ton of research. I had been interested in having it done since 1998, and only got it done last Summer, when I thought the tech was finally there (I felt it had been for the past few years) and when I finally had the time and money.

This will be the first of several posts which serve as a journal detailing my experiences with PRK. I’ll update this page with links to the subsequent journal entries. (Part 2 is up! Details of the day of surgery here: My Laser Eye Surgery, Part II: The PRK Operation, and so is Part 3, detailing the post-op recovery: My Laser Eye Surgery, Part III: PRK Post-Op Recovery.)

I am also not going to argue the case of PRK vs Lasik any further in these accounts, but I am planning for sometime in the future a more comprehensive breakdown of the differences between PRK, Lasik, and the other forms of surgery. Edit: Here it is: Lasik vs PRK: What the Lasik Doctor Doesn’t Tell You.

I am not going to mention any names, as I don’t want my accounts to be mistaken for an endorsement for, nor a warning against, any particular surgery centres. Hopefully this information will be sufficient for any prospective patients to know what questions to ask of their PRK surgeon, and to know what they might be in for with the procedure.

Summary First

It has been over 14 months since my PRK surgery, and I couldn’t be happier. I reached better than 20/20 vision three weeks after surgery, and have had practically no side-effects with my 20/15 vision since around the four-week mark. I was about -4 in each eye with an astigmatism of around 1.00. I see much better now than I did with glasses or contacts before and my eyes are actually less dry and less red than they were before surgery. I have had zero regrets about the procedure.

It’s important to understand though, that my experiences are at the very far end of the bell-curve of results. Relatively few people wind up having quite as good an experience that I’ve had, and most people take longer to heal up or for their vision to cure. Some require various levels of retreatment and some have serious side-effects. Your mileage may vary. This may be a glowing endorsement of the procedure, but it is not a guarantee. You should absolutely look into it carefully, using this account as an idea of what questions you need to answer before you decide to have it done.

As I wrote in the “On Irony and Selection Bias” section in my PRK vs Lasik Primer, “Whatever my outcome, whatever the outcome of your cousin, your co-worker, or everybody you know, the dice are being rolled with each procedure, and each procedure has its different risks. These risks exist and must be looked at on aggregate for each procedure, hopefully before you go under the laser.”

Choosing a PRK Surgeon

This is the most important part of the laser eye surgery process. I’ll tell you from the outset, that cost should absolutely not be a factor. The price of the surgery is largely unrelated to the quality that you can expect. While the cheapest in town probably won’t be the best, neither will the most expensive likely be. Ignore cost entirely.

I live in Vancouver, BC, and from my extensive research, I settled on two places in the area that I’d even consider for my PRK surgery. Both clinics had excellent doctors who had many thousands of surgeries performed, both were very highly recommended by ophthalmologists in town, and both were quite a large step above the rest of the players in town with regard to equipment and experience. However, there was a fundamental difference between the two clinics that made the choice simple for me, and that choice actually went against many of the ophthalmologist’s recommendations.

The fundamental difference was that the clinic I went to performed all of the post-operative after-care, while the alternative clinic did not, instead out-sourcing the after-care to your own ophthalmologist. I’ll try to explain why that difference is so key with PRK, and why perhaps ophthalmologists may have been more likely to recommend the alternative clinic over the one I went to.

While it sounds relatively trivial, in actuality, a huge portion of the outcome of PRK surgery relies on the decisions made during the post-op after-care period. Decisions surrounding the frequency and duration of the steroid drops you take play a huge factor in the healing process. All laser surgeries over-correct a little, anticipating the eye to heal, regenerating some of the cornea that is shaved off for the correction. If you took no steroid drops, you’d heal over a great deal of the correction fairly quickly. So, how much of, how often, and how long you take the steroid drops will determine where the healing process stops. They try to aim for just the right amount of healing that stops at your 20/20 (or better) vision. Everybody heals differently either due to genetics or environmental circumstances, so the custom-tailoring of the steroid dosage is critical to getting the best out of the surgery.

If all that after-care is done by your own ophthalmologist. Even if your ophthalmologist has seen a hundred PRK patients (in reality likely nowhere near that many), then he’s going to have very limited experience. He’s largely going to be following procedure that is generically tailored to everybody, and won’t necessarily be able to tailor the treatment to your particular healing rate.

With my surgery, all the after-care was by the doctors at the laser-surgery clinic that performed my PRK surgery. They were working with the knowledge of tens of thousands of surgeries performed in-house. I had follow-up visits and eye tests at the 1-day, 3-day, 5-day, 5-week, 5-month, and 1-year marks (all included in the price, not that price matters really). I felt far more comfortable having the after-care decisions made based on that mountain of experience, than I would have had it been an ophthalmologist that had little experience or training with laser eye surgery after-care.

It is important to remember that with PRK it’s that first 3-5 days post-op that makes such a huge difference in overall results. For example, on my day three visit the doctor reduced the frequency of the steroid drops in both eyes, but reduced them more in one eye than the other. As is common, they were healing at different rates. On day 5 he stopped the steroid drops in one eye, and had me do just a little bit in the other eye for a couple more days.

That aspect was crucial, had the post-op medication schedule not been custom-tailored to my day-to-day progress, I wouldn’t have nearly as good vision right now, even with the identical surgery performed.

I’d strongly recommend you seek your surgery at a clinic that has a lot of experience and performs its after-care in-house. They will have so much more institutionalized knowledge. And that knowledge matters.

So, while the alternative clinic has an outstanding doctor who has done many thousands of treatments, they didn’t perform the follow-up after-care, which is so crucial. What was odd was that while the ophthalmologists around town would universally approve of both the clinic I went with and the alternative, most of them recommended the alternative clinic that performed no after-care in-house.

The cynic in me says of course every ophthalmologist in Vancouver will recommend the alternative. They not only have a great surgeon, but then they get the follow-up care. There’s significant money in it for them, if they do the follow-on treatment. Whether cynical or not, it’s naïve to think that that wouldn’t influence their decision.

Other Important Questions to Have Answered

As part of choosing the right PRK surgeon and clinic, I recommend you get satisfactory answers to the following questions, before you go under the laser. You’ll have to ask the questions, as they will generally not be forthcoming on their own. I suppose if they gave all this information up front, almost nobody would go through with it. Plus, a lot of people just don’t want to know, and are happy to go in with eyes closed, so to speak.

It’s also important not to save these questions for surgery-day. You’ll be too nervous, and you’ll likely either forget what to ask or be caught up in ‘go-fever’ and not consider the answers carefully enough. The answers you get to these questions need to be considered carefully, and will in large part be necessary in determining who to go to for your surgery.

I’ll give a bit of indication why the questions are important, but if you don’t fully understand why these answers are necessary, I recommend a little more research.

1: What is my dilated pupil size?

This is important in comparison with the answer to the question about treatment zone below. They will generally measure your dilated pupil size on your first consultation visit, but likely only in a mildly dark room and without much time for your pupil to adjust. As a result, take this measurement as a somewhat smaller estimate of your actual fully-dark pupil size.

2: What laser system is being used for mapping, tracking, and correcting the eye? What version of each component is used? What is the latest version of each component?

Not all PRK laser eye clinics use the same laser systems. There are several available. Further, not all clinics are using the latest version of their particular system. There have been significant advances in the technology in the past several years, but sometimes a clinic will spend more money on it’s flashy waiting room, instead of upgrading it’s several year old equipment. The answers to these questions will not mean much to you, but you can then enter them into google to verify and compare the system being used against the latest equipment from that manufacturer.

3: What is the size of the corrected, non-tapered treatment zone in the procedure? What is the size of the tapered transition zone of the procedure?

Make sure your pupil size isn’t substantially bigger than the corrected, non-tapered zone! The ‘tapered transition zone’ doesn’t really provide the actual correction and really shouldn’t be compared to your dilated pupil size. You need to ask for it, so that you make sure that size isn’t being passed off as the ‘corrected’ zone.

For example, my fully-dialated pupil is slightly wider than the corrected treatment zone available from any of the laser eye systems. The transition zone covered it, but I knew that didn’t mean much. The laser system at the clinic I went to were the latest models as of when I had it done, with the largest correction zone available (plus transition zone, but I didn’t count that). The alternative clinic I looked at used a different system, which had a slightly smaller treatment zone, and that was another factor that ruled them out.

I knew going in what having a slightly larger max-dilated pupil than the treatment zone (not tapered zone) would mean. In complete darkness, some of the light entering my eye is not fully corrected, so it’s blurry. This results in really clear lights with a slight blurry halo around them. I decided I was good with this, because the difference was small. Now, after surgery, If I’m in my bathroom at night in complete darkness, I see a halo around the green LED in my safety-outlet. However, when I put the light of my cellphone’s screen on (pointed away from me), it brightens the room just enough that my pupils contract a tiny bit and all the light is going through the correction zone, and therefore there’s no halos. The halo around the light literally shrinks to nothing at all as my pupils contract a bit. This only happens for very bright lights in near total darkness. In real-world situations like driving or walking around at night, there’s way more light than pitch-darkness, so I have zero halos.

4: Is a custom ‘map’ of my prescription measured (WaveFront, etc)? Is this map used to create a custom correction for each of my eyes, or is this map only used to select the nearest ‘preset’ correction?

Some laser systems used by laser eye clinics advertise a WaveFront or custom map, etc, but the custom map of your eye isn’t actually used to create a custom correction for your eye. Instead it is only used to select from a preset correction. Obviously the latter will result in a less tailored solution for your eye.

5: What eye tracking system is used? Does it track the inside of the iris, or the outside of the iris? How many times a second does it track? Does it track in 3D or 2D?

No matter how good a correction map is being applied to your eye, it’s useless if it’s not aligned as perfectly as possible. In the old days of laser eye surgery, the patient had to stare at a reference light and any movement would result in a misalignment of some of the correction pulses. Modern laser systems track the eye and adjust or stop if the eye moves. But, not all are created equal.

Some laser systems in use track only the inside of the iris, which varies wildly during treatment (the iris is constantly dilating and contracting in reaction to all the prodding, light flashes, and emotional reactions). That one’s a deal-breaker. Avoid any system that tracks the centre of the pupil or against the inside of the iris. Most of the latest laser systems will track on the outside of the iris, which is a far more reliable marker, as it does not vary, except with eye movement.

That leads to the frequency of tracking and the nature of movement that can be tracked. Some systems track eye movements and adjust/stop the corrective laser faster than others. Some systems only track in 2-dimensions, while others track movements in 3-dimensions. Obviously, you want the laser to adjust as quickly as possible to eye movements in any direction

6: Which doctor will be performing my surgery?

Once you’ve selected the PRK clinic based on the experience of the doctor, the quality of the after-care, and the equipment being used, you then have to make sure that you know which doctor in the clinic will be doing your surgery. Most clinics have more than one doctor in house, often where one of those doctors has significantly less experience than the head doctor. I wouldn’t necessarily rule out getting my surgery done by a doctor with only a few hundred operations under his belt, because in reality the actual procedure itself is a relatively small part of the overall process, and that doctor is relying on equipment, settings, best practices, and all the expertise that is accumulated in-house. But that said, I want to know who will be performing the surgery and make my decision with that knowledge.

7: What drugs, drops, etc will be provided, and which do I need to get myself?

Where I went, everything was provided in a little bag that I brought home. This included lubricating drops, antibacterial drops, steroid drops (all labeled with large, clear dosage instructions), pain drops, Tylenol-3 painkillers, sleeping pills, a spare pair of ‘bandage contact lenses’, and a pair of over-the-glasses sunglasses. After surgery, I would not have wanted to make any stops on the way home to get any of that. If your clinic does not provide them, then you should make sure you purchase them in advance.

Pre-op Preparation

After you’ve booked your surgery, while you’re going through the two weeks of not wearing contact lenses, the waiting game begins. This is the opportunity to rehash everything you’ve already looked into. It’s the last time to avoid any regrets. You can read up on the statistics, the horror stories, and the success stories. It’s never too late to ask more questions or delay if you’re unsure.

It’s also the time you can spend trying to give yourself the best possible leg-up towards a successful surgery.

Since so much of the procedure is the healing up afterward, I did anything and everything I could think of to help my body out on the healing front. I started taking a bunch of multi-vitamins and omega-3 fish-oils a couple days before surgery and for a few weeks afterward. I also made sure that I was super-well hydrated before and after the procedure and during the healing. I made sure I was drinking more than enough, making frequent trips to the washroom. I made sure that I slept well and that I ate well. I did pretty much anything I could do to help my body’s healing.

I’m not sure how much of all that over-caution helped my optimal recovery, perhaps very little at all. But I am sure that it certainly didn’t hurt. I didn’t want to have any regrets about my surgery, so I did whatever I could possibly think of to help my body out.

One final PRK pre-op tip. Because you’re very light-sensitive after the surgery, many recommend wearing an eye-mask to block out the light. I chose not to, as I’d always gotten a little sweaty while wearing one, and that dampness makes a nice moist bacteria soup, which could only have increased the chance of infection. As a result, even while wearing two-pairs of sunglasses indoors (regular ones with the ‘over the glasses’ pair I was given by the clinic), and even with my eyes closed, the light was still unbearable. I thought I’d be okay, but I wound up needing my wife to tinfoil all the windows in the apartment, no doubt causing my neighbours to suspect I was growing something illicit. Knowing what I know now, I’d have definitely prepped the apartment with tinfoil before the surgery, as it was absolutely necessary.

Continued Reading

Here are my posts on PRK and laser eye surgery, continue reading or, feel free to join the discussion in the comments below!

Laser Eye Surgery Primer: Lasik vs PRK
Lasik vs PRK: What the Lasik Doctor Doesn’t Tell You
My Laser Eye Surgery, Part I: PRK Pre-Op Preparation (You are Here)
My Laser Eye Surgery, Part II: The PRK Operation
My Laser Eye Surgery, Part III: PRK Post-Op Recovery
Halos: A Likely Complication of PRK or Lasik
    

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