In this particular episode of Ask an Eye Doc, you will learn:
- What the acronym LASIK stands for
- What LASIK is
- What is a LASIK flap
- How long LASIK usually takes
This episode will make more sense if you have already listened to the following episodes:
- episode 1 – what is astigmatism
- episode 13 – what is nearsightedness
- episode 14 – what is farsightedness
- episode 20 – what is the cornea.
For you readers out there, here’s the answer in written form:
LASIK is a very common term that most of you have heard. But what is LASIK exactly?
LASIK stands for Laser-Assisted In-Situ Keratomileusis. “In situ” means to leave in its original position, “kerato-” means cornea, and -“mileusis” means to shape. In other words, LASIK is a surgical procedure where the cornea is directly reshaped using a laser.
The reason why you would have LASIK would be to reshape your cornea so that you don’t need to wear glasses or contacts anymore.
The first step of LASIK is the creation of the flap. The flap is a thin slice of your cornea, usually around 20% deep and about 9 mm in diameter. This is classically created with a microkeratome (think mini cheese slicer). New technology allows for the flap to now be cut using a laser instead of a blade. This is called bladeless LASIK and results in a more stable flap.
Once the flap is cut, it is flipped open and the underlying cornea is reshaped using a laser. Anywhere the laser touches, the cornea is ablated (or sort of vaporized). This process usually takes less than 60 seconds, depending on how strong your prescription is.
If you’re nearsighted, your cornea will be reshaped so that it is flatter than it used to be. If you’re farsighted, the corneal shape will be steepened. If you have astigmatism, your cornea will be shaped just enough in each axis so that the astigmatism is neutralized.
Once your cornea is reshaped to neutralize your prescription, the flap is put back on top of the cornea and you are good to go! The actual LASIK procedure takes about 10 minutes per eye. If you’re not squeamish, you can do an online search for LASIK surgery videos to see how it’s done.