| | | | | precisely. Too much steepness makes this |
| IntraLase (also called IntraLASIK or all-laser | | | | impossible. That is why a person with very |
| LASIK) is a way of performing LASIK. LASIK | | | | severe myopia is not a good LASIK candidate. |
| corrects your vision by reshaping the cornea | | | | |
| – the front transparent part of the eye. But if | | | | If a person has corneas which are too thin or too |
| that were to be done right on the top surface of | | | | steep for LASIK, they may well be a good |
| the cornea, it wouldn’t be a permanent | | | | candidate for Intralase. |
| correction. Therefore, a corneal flap must be | | | | |
| created to expose tissue lower down. | | | | Using a Laser to Make the Flap |
| | | | | |
| The cornea has layers, and the surface layer, the | | | | IntraLase uses a second laser to create the |
| epithelium, is continually renewing itself. Cells are | | | | corneal flap, instead of the microkeratome. This |
| discarded and replaced with new cells, and this | | | | gives the eye surgeon more flexibility in exactly |
| makes the epithelium unstable, since it is | | | | how the flap is created. The IntraLase laser is |
| continually changing itself. | | | | extraordinarily fast-pulsed and can be |
| | | | | programmed to penetrate to a microscopically |
| The second corneal layer, the stroma, is stable, | | | | exact depth in the cornea. |
| and that is where laser vision correction is done. A | | | | |
| corneal flap – a thin slice of corneal epithelium | | | | After the treatment area is marked on the eye, |
| – is folded back for treatment, and then | | | | the IntraLase laser is directed over it in a series |
| replaced. It is made with an oscillating blade called | | | | of back and forth passes. Each rapid pulse |
| a microkeratome. | | | | creates a tiny bubble in the cornea, at a |
| | | | | predetermined depth. In a matter of seconds, it |
| Corneal Requirements for a Successful Flap | | | | has passed over the entire treatment area and |
| | | | | filled it with these bubbles below the surface. |
| 1. There needs to be sufficient corneal thickness | | | | |
| -- enough to (a) create the flap; (b) remove | | | | The bubbles break molecular bonds, which loosens |
| some corneal tissue for vision correction); and (c) | | | | the flap tissue. Now your eye surgeon can gently |
| still have enough left in place during treatment to | | | | ease the flap tissue up to expose the stromal |
| avoid any eye injury. | | | | layer for treatment. This flap is thinner than a |
| | | | | standard microkeratome flap. After treatment it |
| If LASIK is done on a person with thin corneas, | | | | is replaced and smoothed over, as in a LASIK |
| the eye can start bulging forward after treatment | | | | surgery. It will heal up by itself. |
| – a condition called keratoconus – because | | | | |
| the cornea is now too thin to contain the | | | | If you would like to have laser vision correction, |
| pressure exerted by the fluid inside the eye. | | | | but have been told you are a poor candidate for |
| Measurement of corneal thickness is done as part | | | | LASIK, you may well be able to have IntraLase. |
| of determining your LASIK candidacy. Too-thin | | | | Be very careful about which eye surgeon you |
| corneas will disqualify a person for LASIK. | | | | choose. Not all surgeons screen their potential |
| | | | | patients equally well. If your corneas are thinner |
| 2. Moderate or mild corneal steepness is also | | | | or steeper than is acceptable for LASIK, you are |
| necessary for a good flap. A severely nearsighted | | | | more vulnerable to surgical error. So choose only |
| (myopic) eye has a very steep corneal curvature. | | | | a highly-qualified and experienced eye surgeon. Be |
| When the flap is created, a certain amount of | | | | sure to ask lots of questions when you go for |
| pressure is placed on the eye so the | | | | your consultation, to make sure you will be |
| microkeratome can cut the flap evenly and | | | | thoroughly screened for safety. |