Optic (Lasik Eye Correction) Surgery

Radial Keratotomy (RK) and Photorefractive Keratectomy (PRK) are other refractive surgeries used to reshape the cornea. RK uses a very sharp knife to cut slits in the cornea, changing its shape. PRK was the first surgical procedure developed to reshape the cornea, by sculpting, using a laser. Later, LASIK was developed. The same type of laser is used for LASIK and PRK. LASIK remains the popular choice.

Eye drops are the only anaesthesia. Sedation is not necessary, but you may take an oral tranquilizer. Your eyelids and lashes are cleansed for sterility and a sticky drape keeps your lashes out of the way. Your lids are gently opened. You look at a blinking red light which keeps your eye properly positioned. During the flap creation phase you have a sensation of pressure and a greyness of vision. Then the laser is used and you will hear a rapid clicking sound. The flap is replaced and it takes about 3 minutes for it to stick down. After the procedure, you will leave with an eye shield and eye drops to help your eye heal. Also, your vision may be a little blurry for a few days. The procedure takes under 10 minutes per eye.

Each pulse of the 193nm laser will ablate or eliminate one three-thousandths of one millimetre using cold energy. It is this level of unparalleled accuracy which allows the programmed Excimer laser to precisely sculpt the human cornea to reduce nearsightedness.

If I Require Surgery to Correct Defects, Can Both Eyes Be Treated at the Same Time?

It is possible for most candidates to have surgery on both eyes on the same day, conditional on the surgeon's approval and the patient's careful informed consent. Even the safest surgery carries some small statistical risks. Therefore, it is most conservative to separate surgeries for the two eyes by some measure of time, depending on patient need and situation.

	LASIK is a surgical procedure intended to reduce a person's dependency on glasses or contact lenses. All of the major three refractive imperfections can be corrected: myopia (near-sightedness), hyperopia (far-sightedness) and astigmatism (image distortion). The surgery permanently changes the shape of the cornea,the clear covering of the front of the eye, using an excimer laser.
A microkeratome knife is used to cut a flap in the cornea. The flap is folded back revealing the stroma (the middle section of the cornea). Then, pulses from a computer-controlled laser vaporize a portion of the stroma and the flap is replaced.

Some patients lose vision.Some patients lose lines of vision on the vision chart that cannot be corrected with glasses, contact lenses, or surgery as a result of treatment.
Some patients develop debilitating visual symptoms.Some patients develop glare, halos, and/or double vision that can seriously affect night-time vision. Even with good vision on the vision chart, some patients do not see as well in situations of low contrast, such as at night or in fog, after treatment as compared to before treatment.
You may be under treated or over treated.Only a certain percent of patients achieve 20/20 vision without glasses or contacts. You may require additional treatment, but additional treatment may not be possible. You may still need glasses or contact lenses after surgery. This may be true even if you only required a very weak prescription before surgery. If you used reading glasses before surgery, you may still need reading glasses after surgery.
Some patients may develop severe dry eye syndrome.As a result of surgery, your eye may not be able to produce enough tears to keep the eye moist and comfortable. Dry eye not only causes discomfort, but can reduce visual quality due to intermittent blurring and other visual symptoms. This condition may be permanent. Intensive drop therapy and use of plugs or other procedures may be required.
Results are generally not as good in patients with very large refractive errors of any type. You should discuss your expectations with your doctor and realize that you may still require glasses or contacts after the surgery.
For some farsighted patients, results may diminish with age.If you are farsighted, the level of improved vision you experience after surgery may decrease with age. This can occur if your manifest refraction (a vision exam with lenses before dilating drops) is very different from your cycloplegic refraction (a vision exam with lenses after dilating drops).
Long-term data are not available.LASIK is a relatively new technology. The first laser was approved for LASIK eye surgery in 1998. Therefore, the long-term safety and effectiveness of LASIK surgery is not known.

Precautions:
The safety and effectiveness of LASIK has not been determined in patients with some diseases. Discuss with your doctor if you have a history of any of the following:

Other Risk Factors:
Your doctor should screen you for the following conditions or indicators of risk:

If you wear contact lenses , it is a good idea to stop wearing them before your baseline evaluation and switch to wearing your glasses full-time. Contact lenses change the shape of your cornea for several weeks after you have stopped using them. It’s best to stop wearing your contacts a month before the operation to make sure the most accurate measurements are taken. This will ensure the best surgical outcome.

The day before surgery, remember to stop using creams, lotions, make-up and perfumes.

No. The laser procedure itself is virtually painless. You will be aware of a support which helps to hold your eye open. A slight pressure may be felt during the procedure. You will be aware of the laser sounds while you watch a red flashing light.

Your eye may burn, itch, or feel like there is something in it. You may experience some discomfort, or in some cases, mild pain and your doctor may suggest you take a mild pain reliever. Both your eyes may tear or water. Your vision will probably be hazy or blurry. You will instinctively want to rub your eye, but don't! Rubbing your eye could dislodge the flap, requiring further treatment. In addition, you may experience sensitivity to light, glare, starbursts or haloes around lights, or the whites of your eye may look red or bloodshot. These symptoms should improve considerably within the first few days after surgery .

No, although 95% of patients with low through moderate ranges of nearsightedness and/or astigmatism achieve normal or near normal natural vision from just one surgery with LASIK. For those who do not achieve this quality of vision from one surgery, enhancement surgery can usually give the rest of the desired correction.

In the U.S. , laser surgery to fix your eyesight is a new deduction. Even though the surgery is optional, it's now deemed a genuine medical expense because it restores a function of the eye. When claiming, you can include travel costs involved in getting medical care, including hotel stays but not meals.

It may take three to six months for your vision to stabilize after surgery. Night vision and glare may persist for this period. After this period, the laser correction will probably last for the rest of your life. The cornea is a very stable tissue.