Comment by pingswept | Hacker News Reader

Comment by pingswept | Hacker News Reader

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I worked on the redesign of a Lasik machine in 2005. As part of this work, I spent a few weeks just watching lasik operations in various locations around the US. I saw several events that made me very wary of the procedure-- specifically, a technician accidentally setting a microkeratome to the wrong size and thereby detaching the corneal flap. I also talked with several patients who were back for 3rd and 4th sessions to fix problems that had occurred previously. It appeared to me that while generally the machines work well, there were occasionally drastically bad outcomes, often due to human error.

Overall, my impression was that the surgery is more risky than one is led to believe. I can't give you any good statistics on how risky it is, but I would not consider doing it myself until I saw credible statistics that suggested that the error rate was very low. From what I've read, approximately 1 in 20 lasik patients are not satisfied with the outcome of their surgeries, and this is from one of the big lasik doctors[1], who I presume would have a strong interest in describing the risks as minimal. But as far as I know, there haven't been any large-scale studies of lasik outcomes.

You might also ask the doctor what machine will be used to do the surgery. When I was watching surgeries, the doctors generally thought that the Visx machines were the best, but they were excited about the arrival of "wavefront" machines that can correct for variations in the geometry of your eyes. I bet that's mainstream by now.

[1]: http://www.medicalnewstoday.com/articles/103194.php

The defense department has done research on the success of Lasik and PRK. They now pay for it and allow you to fly most planes after surgery. I had it done 4 years ago and my vision has been perfect since then.

Is PRK better?

The difference between PRK and Lasik is in the way they reshape your cornea.

In Lasik they create a flap by cutting the cornea and then they use a laser to reshape it, then they reposition the flap back in place.This way the flap acts as a bandage on the wound and reconnects with the cornea. The Flap is never actually healed and may be dislodged even years after the surgery - Although will need significant force like a direct poke in the eye, severe car accident etc.

In PRK a flap isn't created, the laser reshapes the cornea directly (After removing a small epithelial layer) and then a special bandage contact lens is applied to the wound. This is generally considered safer (Nothing to be dislodged), But the healing process is much slower and the time it takes until your eyes are at their best capacity is much longer. As i previously wrote, I was back at work the next day and my sight was almost perfect after 3 days. My cousin had PRK, the total healing time was around 2-3 weeks, and in the first week she could barely open her eyes.

PRK is also considered a little less accurate, but i am not sure why... For a nice comparison see: http://www.lasereyefacts.com/prk-vs-lasik.html

I also chose PRK because I was uncomfortable with the flap, and was willing to risk the painful (and slower) healing process.

While I am not your scenario with the 3 days, I would say that one week is a proper expectation, with some deviation one way or the other.

The pain (in case no one has mentioned it) is very much like leaving a contact in for too long: it feels like your eyeball has been packed in salt. I mean that in both the extreme dehydration sense, and it occasionally actually feels like salt in your eyes.

I had a few instances where it felt like needles in my eyes, and that was my only need to use the prescribed pain medicine. It lasted until I fell asleep from the pain pills.

I do hope this doesn't come across as a horror story: I absolutely, with no hesitation at all, would do it again and would use the same doctor. I am _extremely_ happy, and sing the praises, but wanted to ensure it is an informed decision for those who might be weighing the pros and cons.

Sorry, but I have no expertise to comment on that.

"Better" is always a tricky word.

I think that it is likely a matter of what aspects are important to you (aside from those patients who are forced into using, or excluded from using, one technology or the other).

I received a comprehensive description from my doctor, and chose PRK because I was not comfortable with "the flap," and I was comfortable that there would be some pain and longer healing time. That was my tradeoff, and I am thrilled with how it turned out.

From what I understand talking to an ophthalmologist it's either PRK or Lasik. One of these is always a better fit for a specific patient.

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