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Off Topic: LASIK
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PostPosted: Wed Feb 22, 2006 8:49 am    Post subject: Off Topic: LASIK Reply with quote

Article Digest:
Last Friday, I had LASIK eye surgery performed on my eyes. The results were both immediate and impressive.

A couple weeks ago, I decided to go ahead with LASIK after several friends had undergone the surgery. Several friends and coworkers (including my wife) recommended Dr. Michael Furlong in Campbell, California.

Laser assisted in-situ keratomileusis (LASIK) is an operation that involves cutting a flap from the cornea of the eye. The interior of the cornea is then shaped with an ultraviolet excimer laser and the flap replaced. Using the flap greatly assists the healing process and is the reason when LASIK is so popular (as compared to PRK or LASEK eye procedures). The main requirements for LASIK candidacy are reasonable prescription (-0.75 to -11 diopter nearsightedness, +0.75 to +4 diopter farsightedness, and 0.75 to 4 astigmatism), a pupil diameter that is smaller than 8.5 mm, and a corneal thickness greater than 500 microns. (Requirements may vary due to prescription and specific eyes.)

The Monday of the week prior to my operation, I went in for a consultation to determine if I would be a candidate for LASIK or CustomLASIK (a more recent innovation in LASIK allowing the correction of higher order aberrations in the eye). At the consultation, they determined that I fit the requirements for CustomLASIK. The main requirement that I'm aware of for CustomLASIK (in addition to those requirements for traditional LASIK) is to not have thin corneas. The minimum corneal thickness desired is 500 microns (average thickness is 520 microns). Luckily, my corneas were in the 580 micron ball park. Everything else checked out and they agreed that they could improve my -8.5 D (left eye) and -9.5 D (right eye) myopia and astigmatism (which is bad enough that the 20/something rating isn't used anymore - it's somewhat worse than 20/4000).

The Tuesday before my operation (St. Valentine's Day), I went in for my full preoperative examination. During the hour at the office, they measured my exact prescription (with my eyes dilated), produced a wavefront mapping (a picture of how light rays are refracted by my eyes), and did a few other tests to check the health of my eyes. Having completed that, I was ready for the operation (and I got a recipe for Orzo Risotto while waiting for my eyes to dilate).

On the day of the surgery, I arrived at the doctor's office at around 10:40am (and was on my way home by 11:45am). After signing my release forms, I paid for the operation and was given a small pill (supposedly, a fast acting sedative). I placed the pill under my tongue and waited with Tina in the waiting room for a few more minutes. Then I was taken into a ready room where my eye lids were sterilized and a few final instructions (which I don't remember) were given to me.

They noticed that I was still quite anxious, so they asked if I wanted another sedative. Since the first one was obviously a placebo (or I'm immune to sedatives), I agreed to a second one.

To help calm me down, the staff (and the gentleman prepped for operation before me) chatted with me. As the other gentleman was taken into the operating room, the staff continued to talk to me about chocolate and food. I'm not sure how much time passed as I talked about potatoes and protein content in vegetables.

Soon, I was taken into a dimly lit room where a man (who turned out to be Dr. Furlong) entered and applied some eye drops (anesthetic drops, I think). After a few more minutes of talking about food, I was ushered into the operating room.

Dr. Furlong asked me to sit and lie down on an operating bench. After lying down, I asked for something to hold onto. They gave me a Nerf football to squeeze.

They covered up my right eye and then started with my left eye. Dr. Furlong explained each step of the operation. First they insert something to keep the eye open (so you can't blink) called an eyelid speculum. Suction is then applied to the eye (to keep it from moving) and a device called a microkeratome cuts through the top of the cornea to form a 160 micron flap. The flap is folded up and a computer controlled laser reshapes the internal corneal tissue through a series of quick blasts. The flap is then folded back down and the eye immediately starts to heal.

What I remember, is tiny pin pricks as Dr. Furlong put the device on me that pulls open my eye lids. I remember casually commenting that I could feel that and the numbing eye drops might not be working. Dr. Furlong reminded me that they didn't numb my eye lids and to please look at the blinking red dot. I looked up (which was straight ahead since I was lying down), and saw a blinking red dot surrounded by a bluish white circle or insanely bright light. It seemed to me that the circle of light was so bright that the rest of the world turned dark as my eye adjusted to the brightness of the light.

Then Dr. Furlong said I'd feel some pressure and the lights would go out (probably not what he said, but I don't remember the exact words he used). Everything started to get dark and within a couple seconds I couldn't see anything anymore - the world had faded out to black. I swear Dr. Furlong asked me to keep looking at the red dot - but there was nothing to look at. I might have remembered incorrectly since I did have a double dose of sedatives.

At this point, I felt something rotating on my eye (the microkeratome). No pain, no irritating, I just felt the movement. Then the world started to fade back and the circle of light with the red dot was back - except now it had both a crisp and hazy quality to it.

Then there was a repetitive buzzing, cracking sound and a strobing light that seemed to come from a different direction every time it went off. This seemed to take a lot longer than I expected. It was probably less than a minute, but it seemed to take a quite a while. At the same time, I could start to smell a light odor that reminded me of melting rubber. I was later told I was smelling the burning flesh. There was a device that was vacuuming up most of the smell from the air.

Through the whole operation, Dr. Furlong's voice was there telling me what to do (look at the red light). Meanwhile, I kept thinking: What happens if I accidentally stop looking at the red light? Keep looking at the light; keep looking at the light. Should I be squeezing the football this hard? Being a primarily visual person (and generally nervous when it comes to my eyes – so nervous I never even tried contact lenses because I couldn’t abide the thought of sticking my fingers in my eyes everyday), I usually just close my eyes when I want to avoid an uncomfortable situation or to calm down. Well, unfortunately, I couldn’t – I was forced to watch the blinking red light.

Then the flap was replaced and Dr. Furlong started swabbing my eye with something. I don't know what he was doing, but it just looked like he kept brushing my eyeball - like when I'm cleaning the CCD of my Nikon D100, except instead of doing it once, he kept swabbing and swabbing. He explained that the corneal flap was sealing itself (like a living bandage). Then he stopped and released the eye so I could finally close it.

The operation was repeated on my right eye, but much faster (it seemed).

In less than ten minutes from when I laid down, I sat back up and was told I could open my eyes (because I had closed them as soon as possible). I opened my eyes and could actually see! It looked like I had a soft focus lens on though. The staff noticed that I was quite pale and gave me a Kern’s Mango Nectar. I have to say, I was pretty freaked out over the whole experience, but I made it through.

After a few quick checks, Dr. Furlong had his assistants tape these plastic shields on my eyes (to keep me from accidentally rubbing them) and released me. I don't actually remember much else - I think after the adrenaline wore off, the double dose of sedatives finally kicked in.

The next morning, when I woke up, I opened my eyes and was amazed. The world wasn't perfectly crisp, but I could focus on basically everything I wanted to. The image I could see would be sharp and slightly hazy at the same time. (As if I had a sharp, high-resolution image superimposed with a blurry one.) I was most amazed by the ability to look around without moving my head. (When wearing glasses, the only part of the world that was in focus was the area covered by the lenses. That meant looking up, down, left, or right meant the world was out of focus.) Now, with my post-surgery eyes, I could see - it was amazing. Plus everything within four feet of me looked much bigger than ever. With glasses, everything seemed to have been shrunk, but now, everything was bigger than life.

I went in for my first post-operation examination and there it was determined that I had 20/20 vision in my left eye and 20/15 vision in my right eye. They told me the haziness was due to inflammation and would reduce over time as my eyes healed.

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PostPosted: Wed Feb 22, 2006 10:34 am    Post subject: Get well soon Reply with quote


Good to hear things went ok for you!!
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PostPosted: Wed Feb 22, 2006 11:51 am    Post subject: Did you find out? Reply with quote

Did you ask what would happen if you didn't focus on the red dot?
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PostPosted: Wed Feb 22, 2006 2:14 pm    Post subject: Reply with quote

Interesting story, thanks for sharing!

In the current issue of Make magazine Tim O'Reilly writes a little bit about his recent LASIK experience. He said the doctor told him that if he didn't look at the light the laser would detect that and would automatically shut off.
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Joined: 27 Sep 2005
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Location: Florida

PostPosted: Wed Feb 22, 2006 3:42 pm    Post subject: Reply with quote

I know this is kind of off topic, but that picture of those flowers is very pretty.
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PostPosted: Wed Feb 22, 2006 4:41 pm    Post subject: Amazing story Reply with quote

I took am very anxious when it comes to my eyes... your story was very encouraging. Great to hear such good news.
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PostPosted: Wed Feb 22, 2006 4:50 pm    Post subject: mono vision Reply with quote

5 years ago, at almost age 50 and with coke bottle glasses near sightedness, I went for it, too. I did it when it was "experimental" and they only did one eye at a time.

During surgery the little red light was a problem. One of my eyes is "lazy" and wanders a bit. I thought I was focused on the light, but the eye was actually moving. 5 years ago the laser did not shut off for this, but the doctor sternly warned me to re-focus, which I could not do. He had to stop and let me get re-oriented a couple times.

Eye one was easy. Eye two was horrible, but it all worked out. Somehow right after surgery, when the flap was floating, my eye lid had a spasm that tore it loose. It felt like tobasco in my eye for several hours until the doctor saw it, freaked out, carefully replaced the flap. He was not happy with it and said there was a micro-wrinkle. I was just happy to get the tobasco pain out of my eye.

After healing, the vision was fine - superb. I had my eyes treated differently - one for near vision and one for far vision. It took all of about a week to get used to it and pay little attention to the difference.

Now, 5 years later, I have had to get fitted for reading glasses. The near vision is slipping due to aging of the lens in both eyes. I can still do without glasses entirely, but when tired I have too much fatigue reading without correction. My doctor said I should never need bifocals or distance glasses the rest of my life! That is awesome.

All in all, this is a wonderful new technology that can correct a disability for life. It is well worth the cost, even the very high cost I paid to be an early adopter.
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PostPosted: Wed Feb 22, 2006 4:52 pm    Post subject: Reply with quote

I got LASIK done a year and a half ago. I'm quite happy and don't regret it at all, but I did notice that the sight in my right eye degraded a bit a few months after the surgery... I can still pass a 20/20 test but my left eye is a definitely clearer than my right eye. When I went back for my checkup, the eye doctor said it was still within parameters and the difference was so small that it isn't even measurable by the LASIK machine (in other words I couldn't get it corrected).

My only complaint is the halos that I see when driving at night from street lamps, oncoming cars, traffic lights, etc. My eyes are just ultra-sensitive to high contrast situations now, like watching a brightly lit TV screen in a dark room. It's something I've gotten used to though, and overall, it's a hell of a lot better than having to wear glasses (which have their own visual aberrations).

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PostPosted: Wed Feb 22, 2006 5:58 pm    Post subject: eyes Reply with quote

Congratulations on your eyes.

How much did it cost?

Can you post a follow up article about the haziness associated with the healing process?

Thank you,
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PostPosted: Wed Feb 22, 2006 7:34 pm    Post subject: The PRK perspective Reply with quote

I just had PRK done on both of my eyes this past Thursday and thought I would share my perspectives. For those who aren't familiar, PRK stands for Photorefractive Keratectomy. A similar procedure called Laser-Assisted Sub-Epithelial Keratectomy (LASEK) differs from PRK in whether the epithelium is preserved. The epithelium, is a soft, rapidly regrowing, outermost layer of the cornea in contact with the air. The epithelium can completely replace itself within a few days. Both PRK and LASEK permanently change the shape of the anterior (outermost) central cornea using an excimer laser to ablate (burn off) a small amount of tissue from the corneal stroma at the front of the eye, just under the corneal epithelium. In both PRK and LASEK, the epithelium is softened (with alcohol) and detached from the eye and removed prior to the ablation. In PRK, the epithelium is discarded. In LASEK, the epithelium is preserved and replaced after the laser ablation is complete. By comparison the epithelium is preserved in LASIK, which accounts for the rapid return of visual acuity for those lucky enough to qualify for LASIK.

PRK versus LASIK

Because it does not involve a permanent flap in the deeper corneal layers, (as in LASIK), the cornea's structural integrity is less altered, but there is more pain and visual recovery is slower. PRK does not run the risk of dislocated corneal flaps which may infrequently occur with trauma even years after LASIK.

I opted for PRK after two different Laser Surgery centers determined that my corneas were slightly too thin. The actual procedure was relatively uneventful. I was given a valium pill just moments before I went to the operating table. The valium was less about anxiety during the procedure and more about making sure I was nice and sleepy by the time I got home. The procedure involved the aforementioned alcohol treatment to remove the epithelium. During this step, a disc was pressed onto my eye for about 10 or 15 seconds so I couldn't see anything. Once the epithelium was removed, I was told to focus on the red light, which was blurry throughout the whole process. For whatever reason, I found it pretty easy to focus on the blurry light. The doctor's assistant counted down through the procedure so I knew how much time was left.

Once the laser was done, the doctor washed out my eye with a cold saline wash and then inserted a very thin contact lens that stayed in my eyes for the next four days. She repeated everything on my left eye and I was done in less than 10 minutes.

I started feeling discomfort in the car on the way home. I have to say, the pain was pretty bad that night (Thursday) and through the next day (Friday). The doctor had prescribed oxycodone and I was glad I had it. Every time I took a pill, I ended up sleeping for a couple of hours. I was told that sleep is good for recovery in PRK. I was also given four different types of drops to use: a steroid (7 day use), an antibiotic (7 day use), a pain reliever (4 day use), and natural tears (use as needed from here on).

I went in for my follow up the next morning (Friday) and my vision was about 20/20 in one eye and 20/25 in the other. They were surprised to see my vision this good since I had no epithelium. They said that my vision would proceed to get worse over the next couple of days while the epithelium grew back over my pupil.

By the morning of the third day (Saturday) the pain was subsiding, but the blurriness they talked about appeared. I gave up on watching TV that day and pretty much listened to books on tape all day. Sunday, the third day, was more of the same, with clarity getting better in one eye. By the morning of the fourth day (Monday) I could see fairly well in both eyes and I opted to go back to work. Don't get me wrong, things were still blurry, but I could still read the computer screen.

I went back to have the contact lenses removed on that fourth day (Monday). They checked my vision before removing the lenses and my vision had degraded (as compared to day 1) to about 20/30 in one eye and 20/40 in the other. Again, this was just the blurriness caused by the healing epithelium. Once they removed the contacts, I could feel the grittiness of the epithelium. No pain, just kinda like there was some small dust particles under my lids.

So here I am at day 6 and according to the eye chart on the wall, I'm at about 20/25 and 20/30 in my left and right eyes, respectively. They are getting better by the day. I'm told they should both settle in close to 20/20 over the next couple of weeks.

Obviously, PRK is a much more painful, more lengthy recovery than LASIK. If I had to do it over, I'd probably opt to do one eye at a time, just so I wouldn't have to deal with the blurry vision for so long. Other than that, t's still worth it to me in the long run.

Andrew (a-aranda-at-alumni-dot-utexas-dot-net)
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PostPosted: Wed Feb 22, 2006 10:04 pm    Post subject: follow up a month later Reply with quote

Great article! The graphics totally help! Please give a followup post like a month later. I'm especially curious about the night vision/halo effects.

If there's a suction holding your eye still, why do you still have to look at the red light?

Too bad they can't sedate your sense of smell. Burning flesh would freak me out. I'll have to remember to only breathe through my mouth if I ever get LASIK. =)
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PostPosted: Wed Feb 22, 2006 10:49 pm    Post subject: Modern technology is Great! Reply with quote

That is just wonderful! Good for you. Now no more dirty glasses to clean. You can steam those creations without fogging up your glasses. Cool No more specs to lose on the top of your head. Enjoy your New World. Shock I am happy for you.
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PostPosted: Thu Feb 23, 2006 2:17 am    Post subject: Re: Lasik Reply with quote

Thanks for taking the time to share your experience. Now I have some more info to take to take to the eye doctor and know what to expect. Does anyone know of Lasik correction for farsightedness? Would the procedure have to be repeated as the patient ages? Keeping track of several pairs of glasses is annoying. Congratulations on your vision freedom!
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PostPosted: Thu Feb 23, 2006 4:23 am    Post subject: Good Luck! Reply with quote

I had mine done last year. I can see very well now, however I now have developed "dry eyes" and require a prescription for Restasis and it's not cheap. It does work though. The added solution was punctal plugs for the tear duct drains to keep the fluid in my eyes instead of letting it drain. Well, my left eye is so wet that I need to frequently wipe it dry and my right eye still needs additional drops. I'd rather have my glasses back. Hope works out well for you.
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PostPosted: Thu Feb 23, 2006 1:42 pm    Post subject: My surgery Reply with quote

I had LASIK 8 years ago (I was 22 at the time). My doctor explained every detail to me before the operation (not during) so I was pretty well prepared (the doctor also did my fathers cataract). Anyway my experience was very similar to yours only I didn't get any sedatives and I did one eye at a time (week apart).
Despite the fact that the device that keeps your eye open and the suction device (the micro saw that cuts the flap) were slightly painful, I enjoyed the procedure very much. When it was finished the doctor just closed the flap (I don't remember him using any swab like you describe) and BAM (sorry Emeril) I could see clearly! Immediately! I personally enjoyed the procedure since I looked at everything as a soreal movie happening around me and tried to distinguish what was happening such as when the laser fired and the burning smell starts Wink
I personally recommend this treatment to anyone who can go through it, I found it really helpful and enjoyed it a great deal. Even now 8 years after removing my glasses (for good) I still get to bed late at night and start looking for my glasses on my nose. I'm not sure if I see exactly the same as before, but it doesn't matter since its good enough and I can ride my motorcycle.
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