All About LASIK Surgery
Many people love the idea of getting rid of their glasses and contacts, but they cringe at the thought of having a procedure performed on their eyes. We’re hoping that we can help people overcome their fears by providing accurate and helpful information about LASIK and other refractive procedures. With time tested technology and fine-tuned surgical skill, this procedure is one of the safest, most effective eye treatments available. And we believe the benefits far outweigh the risks.
What is LASIK surgery exactly?
It’s the use of a laser beam to modify the shape of your cornea such that your vision will improve. So let’s look at how our vision works, why it might be less than perfect, and how LASIK surgery changes it.
How does our vision work?
It all depends on light. Our eyes are balls, made such that they receive light rays on the front side and bend them (refract them) to focus on the inside back surface of the eye (the retina). It’s very like the way a traditional camera directs light onto a film inside it.
So the object from which the light rays have been reflected to our eyeballs shows up as a little image on the retina, a tiny upside down picture of itself. There’s a large nerve at the back of each eye called the optic nerve which then transmits this image information to our brain and our brain understands and interprets it and tells us, “That there is a tree!”
So why, for some of us, does that tree look blurry or indistinct or distorted? Because the image information sent by the optic nerve was deficient in some way so the brain didn’t receive enough information to interpret correctly, and maybe it told us, “That there is a telegraph pole!”
That happens when the cornea isn’t perfectly round and the light rays are not refracted correctly, so they don’t form a perfect image. This is where LASIK surgery enters the picture, so to speak.
Kinds of laser eye surgery
LASIK stands for Laser-Assisted in-situ Keratomileusis. There are 3 main varieties of LASIK surgery, only one of which is correctly called “LASIK surgery”, and it’s principally used for people who are very shortsighted or very longsighted. The other kinds are:
- PRK (Photorefractive Keratectomy), which was the original kind and is still sometimes used. It involves gently scraping some surface cells off the cornea and then using a laser beam to re-shape it.
More about PRK
- E-LASIK, or Lasek (Laser Epithelial Keratomileusis), which is used for people with mild to moderate short-sightedness, whose corneas are too thin and delicate for regular LASIK surgery. A finer blade is used to cut a tiny flap from the epithelium of the cornea, but before it’s lifted, an alcohol solution loosens the edges. Then the LASIK surgery re-shapes the cornea and the flap is replaced.
More about Lasek with an "e"
- Epi-LASIK, (Epithelial Laser In-Situ Keratomileusis), which, like e-LASIK, is for those whose corneas are too too thin and delicate for regular LASIK surgery. Instead of cutting the tiny flap and using alcohol to loosen it, the flap is gently separated by a specially designed instrument; then the laser does its work as in the other methods.
More about Epi-LASIK
What is a laser?
“Laser” is a word now, but originally it was an acronym for light amplification by stimulated emission of radiation. It’s a kind of light beam that we specifically create for a purpose, and can be ultraviolet, infrared, or within our vision range. There are many kinds of lasers, named according to how they’re created: solid-state lasers, gas lasers, semiconductor lasers and excimer lasers, for example.
All laser beams are a single color (as opposed to regular white light, which contains all colors), and they’re directional, meaning that the photons (light particles) contained in the beam are in lockstep, so the beam is highly focused and concentrated. If you’ve ever seen a laser pointer used in a classroom, for instance, you’ll get the picture.
Which lasers does LASIK surgery use?
LASIK surgery uses ultraviolet beams called excimer lasers.
Traditional LASIK surgery
In traditional LASIK surgery, a round, thin flap is cut from the cornea’s surface in a way that leaves part of it still connected. It’s gently folded back to expose the stroma, the next level of tissue. Then an excimer laser is directed precisely onto the stroma to vaporize tiny areas, thus removing irregularities that are causing defective vision. The little flap is then replaced and the eye heals itself in a day or two.
All Laser LASIK
Many LASIK surgeons use the IntraLase laser to create the LASIK flap. Click here to find out more about IntraLasik.
Wavefront LASIK Surgery
The most recent step forward in LASIK surgery was in 2002, when the FDA approved a procedure called Wavefront LASIK Surgery. It has so far approved 3 such systems.
In Wavefront LASIK Surgery - sometimes called "Custom LASIK" - a computerized device beams a light at each eye, which lands on the retina. Then it rebounds to a sensor which tracks the irregularities of the front of the light wave as it comes from the eye. Using this information, the computer program makes a 3-D map of the precise shape of the person’s cornea.
The LASIK surgeon translates this map of wavefront data into a mathematical formula on the computer and from that, programs corrections into the excimer laser.
The laser is thus guided in vaporizing tiny amounts of eye tissue to reshape the cornea, and in this way, the eye’s refractive errors are corrected.
Advantages of Wavefront LASIK Surgery
This type of LASIK surgery can correct what’s called higher order aberrations (haloes, glare and blurry images), as well as the lower order aberrations (astigmatism, short-sightedness and long-sightedness).
The results are also a little more predictable than those of traditional LASIK surgery. And further, studies done so far suggest that over 90% of people who have Wavefront LASIK Surgery achieve 20/20 vision, as compared with less than 80% of people who have traditional LASIK surgery.
Is Wavefront LASIK Surgery best for me?
That’s a question to ask your LASIK surgeon, because the answer depends on many factors. For example, if your eyes are particularly dry or your corneas too thin, you may do better with traditional LASIK surgery. Other eye conditions are relevant too, and the degree and type of your visual irregularities.
Choosing a LASIK surgeon
Although there are many LASIK surgeons these days, they aren’t all equally desirable. Before choosing one, interview several and ask lots of questions. And before asking the questions, know what answers you should get!
That means doing research for yourself, because your eyes are not replaceable and you’ll want to trust their well-being only to a properly trained, certified, professional and trustworthy LASIK surgeon. And choose a LASIK Surgeon who you feel personally comfortable with, because no surgery, LASIK or otherwise, is guaranteed to proceed perfectly. If there are any post-op complications, you want to be confident your LASIK surgeon will listen to you, answer your questions, and follow-up conscientiously.
Other LASIK Resources and Information