They use a scapel to create the flap. You won’t be able to move your eyes because they have an instrument that holds the lids in place and you’re medicated so that you’re completely relaxed. You probably will be able to move your eyeball, but don’t try it. They may also have some instrument to keep the eye itself still. I had the old surgery, under the knife, but don’t recall if they had something to hold my eyeball still, but they did use something on my lids.
They don’t use a scalpel. The flap is created with an instrument called a “microkeratome”, which looks kinda like a cigar cutter. Your eye is held still with a vacuum-powered suction cup. You can’t see a thing while the flap is being created, nor can your eye move. The cutting takes around 2 to 5 seconds.
For a blow-by-blow account of what the surgery is like, read my 8/20/2000 post in this old thread, Gettin’ my eyes lasered…
Let me start out once again by pointing out that this is one of those questions you should be asking your eye doctor rather than your friends. Then I’ll dive in and respond again anyway. 
When I had my LASIK surgery done, I asked the doctor about my daughters and if/when they should consider it. He told me that his company won’t even consider performing the operation on anyone under 18 (because your eyes are still changing prior to that), and preferred not to perform the procedure on anyone under 21 (same reason). After that, no problem.
I also asked him what the operation would be like seven or eight years from now. He said that folks were working on improved laser technology that could reshape the cornea without the need for making that first incision (IE, not having to perform the “flap” portion of the current “flap and zap” procedure). He said this would be a significant improvement because making that flap was responsible for roughly 90% of the problem situations that occured during the procedure. He also said that he thought this was more like ten years away than seven.
What happens if you move your eyes when they’re doing it?
I asked my doctor that question, too. He said that if you move your eyes while they’re making the flap and it affects the cut, they simply stop, put the flap back, have you come back in a few months after the flap has completely healed, and try again.
If you move your eyes during the actual lasering, the machine detects it (long before you can move them a significant distance), turns off the laser, and waits until you’re stationary again before restarting.
Note that the actual lasering only takes about five seconds per eye.
I used to have 20/400 in one of my eyes, then it got worse. I asked the tech what it would be called then, and she said “count fingers”, referring to the fact that they couldn’t test my eye on the eye chart (couldn’t see the “E”) . So, was this tech not speaking accurately?
The eye chart only goes so far into poor vision. If you can only read the top E, your vision, as I recall is 20/400, the next line being 20/200. I may be wrong and “E” may be 20/200. That’s all the chart can tell. 20/200, incidentally is the beginning of legal blindness, which means that if you have uncorrectedvision of 20/200 or worse, you are entitled to all the encoutrements of one who is blind. Of course, a lot of us have much worse vision but are correctable with corrected lenses.
The strength of the corrected lens is the diopter number, and at this point, stuff like 20/800, etc. is meaningless and not measurable anyway. Just the diopter needed to correct your vision. Like mine was -8 diopters, but you cannot equivalate that to a 20/ number (way off the chart).
So if some one is testing you just with a chart and you cannot even read the top line, they have no idea what diopters you need and can write stuff like “cf” meaning “count fingers.” That’s legal blindness if it cannot be corrected. If for some reason it cannot be corrected (due to a nerve disorder or a retina problem, such as macular degeneration or glaucoma) there are no diopters that can correct the problem. In that case, even an opthalmologist will write “cf” or something similar, if that’s all you can see.
Incidentally, I’ll give one more try for what LASIK stands for: laser assisted situs in keratamilieu. If some one knows the correct one :)please post it. Also, incidentally, the laser surgery done prior to LASIK (and probably still being performed in some cases today) was called PRK, which stands for photorefractive keratatecomy.
The scapel, which I had, was called RK, radial keratomy.
thanks (yes, I was told 20/200 for my GOOD eye which CAN see the E, and before the ‘cf’ was told 20/400 for my bad eye). But, I was under the impression that as long as it was correctable, I wasn’t entitled to the tax and other gigs as legally blind. You mean I’ve been missing out!?!?!?!?!? damned eye doctors. (my ‘bad eye’ isn’t quite correctable to 20/20 anymore, but my good eye is)
I should have been more specific. As long as it is correctable to less than 20/200 in either eye, you are not legally blind. Also, if you have a restricted field of vision due to some problem, and your angle of vision subtends a certain minimal degree at various coordinates, you also will be legally blind. (That’s a complicated one and entails calculations at various coordinates.) All the above refers to your WEAKER eye.
My wife had the procedure done on both eyes in August. She’s already had to go back for the left eye, it’s not holding it’s correction. On January 23rd, she goes back for the right. Same problem.
The proceedure is amazing, I watched a man have both eyes done before my wife’s re-do. One can do this WITH REMARKABLE CLARITY- because there is a high-res video tap hooked into the viewing system that the surgeon uses. You see what she sees, and see it in real time on a large Trinitron. They weren’t going to let me watch my wife’s Do-Over, because it’s a bit more grisly, and because she’s my wife. When they found out I did EMS work, they left on the monitor. 
((Before I get into the whole schmeg, the quote I used posed a question. You are told NOT to move your eye, and the laser itself is firing for around 5-10 seconds. There is a Flying Spot laser that is used by some facilities, that tracks the movements of your eyeball, and fires “On The Fly” so to speak.))
The flap is created by a machine that, in one smooth move does several things. It lowers down, and presses the cornea flat. ( The cornea is naturally curved, of course). It then IMMEDIATELY moves a straight blade across the cornea, severing the two upper layers and exposing the lower layers of the cornea. This cut moves across about 80% of the cornea, so the area left uncut makes it a flap, instead of a total removal. Prior to the cut, a spider-web like pattern is dye tranferred onto the surface of the eyeball,using a neat little pattern device. This is used after the proceedure, to allow the surgeon to re-align the flap with the surrounding eyeball surface. Even though the flap IS attached still with about 20% of the corneal surface, there is understandably the chance of slippage or wrinkling as the cornea is re-placed.
Okay, it’s patterned, and the device flattens and cuts. That happens in several SECOND- no more. My sense, after watching the man get his surgery is that the cut itself took under two seconds.
Then, the surgeon literally lifts away the cornea’s upper layers. The eyelids are held up and away by a device IDENTICAL to the clamps used in “A Clockwork Orange”. An attending technician does indeed wet the eye down the entire time, aside from when the cut is actually happening, and when the laser is doing it’s thing.
Now, the cornea has been delicately flapped aside. The laser itself has already been programmed, because your eye was photographed twice in another room, by a clever machine that lets the computer that aligns the laser use a concentric circular pattern. It knows exactly where to shoot, to re-form the corneal layers. You have to hold your head VERY still for 5-10 seconds, no more. The eye was numbed already, before the cut, right?- so there is apparently no pain. My wife described a tugging- which made her nauseous, but didn’t hurt.
When wife had her do-over, it was more delicate. They had to MANUALLY pull up the corneal area that had previously been cut by the machine. Fascinating to watch, and I’ve a strong stomach. Then, the laser did it’s corrective firings, the cornea flap was placed back and smoothed out, etc.
I make my living with my eyes, and at 38 I am apparently very lucky that I still have 20-15 eyesight in both eyes. ( This amused the Opthalmatic Technician who checked wife’s vision, then did me cause we had time to kill. Pissed my wife off…) I dread the idea of corneal cuts. As neato as the technology is…well…she’s going back- AGAIN. I am aware that I cannot imagine the joy and change in life of having VERY bad eyesight corrected for the first time in one’s life, at the age of 38, let’s say. I just pray I never have to face that option.
If this is where it is now, I cannot IMAGINE where it’s going. They did tell me that there is work on perfecting a laser to do the corneal cut- so that it does not have to be flattened and cut mechanically by a blade. They feel it will cut down ( pardon the pun ) on scarring, and be that much more precise. Incredible. To me, the technology involved in cutting BETWEEN layers of the human cornea with routine precision is far more astonishing than the technology of firing a laser INTO the corneal layer to adjust it’s angle in a minute way.
Cartooniverse.
I hated glasses but I hated contacts even more. They burned when I put them in. But anyway I do lots of sports like wakeboarding, dirt bike riding, scuba diving ect. And glasses are horrible for those sports contacts worse.
I had the old RK done like barbitu8 too(before lasek). And I have 20/20 now. And like not wearing glasses so much better. I don’t even care if I need reading glasses when I get old. I mean glasses aren’t that big of a deal when you read. So go for it! Worth every penny I think.