LASIK eye surgery is the best known and most commonly performed laser refractive surgery to correct vision problems. Laser-assisted in situ keratomileusis (LASIK) can be an alternative to glasses or contact lenses.

During LASIK surgery, a special type of cutting laser is used to precisely change the shape of the dome-shaped clear tissue at the front of your eye (cornea) to improve vision.

In eyes with normal vision, the cornea bends (refracts) light precisely onto the retina at the back of the eye. But with nearsightedness (myopia), farsightedness (hyperopia) or astigmatism, the light is bent incorrectly, resulting in blurred vision.

Glasses or contact lenses can correct vision, but reshaping the cornea itself also will provide the necessary refraction

Risks

Complications that result in a loss of vision are very rare. But certain side effects of LASIK eye surgery, particularly dry eyes and temporary visual problems such as glare, are fairly common.

These usually clear up after a few weeks or months, and very few people consider them to be a long-term problem

LASIK surgery is usually not advisable if you:

• Have an eye disease that causes the cornea to thin and bulge, or if you have a family history of it
• Have fairly good overall vision
• Have severe nearsightedness
• Have very large pupils or thin corneas
• Have age-related eye changes that cause vision to be less clear
• Participate in contact sports that may be associated with blows to the face

How you prepare

Steps you can take to prepare for surgery include:

• Know what surgery may cost you.LASIK surgery is usually considered elective surgery, so most insurance companies won’t cover the cost of the surgery. Be prepared to pay out-of-pocket for your expenses.
• Arrange for a ride home.You’ll need to have someone drive you to and from your place of surgery. Immediately after surgery, you might still feel the effects of medicine given to you before surgery, and your vision may be blurry.
• Skip the eye makeup.Don’t use eye makeup, cream, perfumes or lotions on the day before and the day of your surgery. Your doctor may also instruct you to clean your eyelashes daily or more often in the days leading up to surgery, to remove debris and minimize your risk of infection

What you can expect

Before the procedure

Long-term results from LASIK tend to be best in people who are carefully evaluated before surgery to ensure that they are good candidates for the procedure.

If you wear contact lenses, which can change the shape of your cornea, you’ll need to completely stop wearing them and wear only your glasses for at least a few weeks before your evaluation and surgery. Your doctor will provide specific guidelines depending on the type of contacts you wear and how long you’ve been a contact lens wearer.

During the evaluation, your eye doctor will ask about your medical and surgical history and give you a comprehensive eye examination to evaluate your vision and assess whether you can undergo the procedure safely.

Your doctor will look for signs of:

• Eye infection
• Inflammation
• Dry eyes
• Large pupils
• High eye pressure

Your eye doctor will also measure your cornea, noting the shape, contour, thickness and any irregularities. Your eye doctor will evaluate which areas of your cornea need reshaping and determine the precise amount of tissue to remove from your cornea.

Doctors generally use wavefront-guided technology to evaluate your eye in detail before LASIK surgery. In this test, a scanner creates a highly detailed chart, similar to a topographic map, of your eye. The more detailed the measurements, the more accurate your eye doctor can be in removing corneal tissue.

Before surgery, your doctor will discuss the risks and benefits of LASIK surgery, what to expect before and after surgery, and any questions you may have.

During the procedure

LASIK surgery is usually completed in 30 minutes or less. During the procedure, you lie on your back in a reclining chair. You may be given medicine to help you relax.

After numbing drops are placed in your eye, your doctor uses an instrument to hold your eyelids open.

A suction ring placed on your eye just before cutting the corneal flap may cause a feeling of pressure, and your vision may dim a little.

Your eye surgeon uses a small blade or cutting laser to cut a small hinged flap away from the front of your eye. Folding back the flap allows your doctor to access the part of your cornea to be reshaped.

Using a programmed laser, your eye surgeon reshapes parts of your cornea. With each pulse of the laser beam, a tiny amount of corneal tissue is removed. After reshaping the cornea, the surgeon lays the flap back into place. The flap usually heals without stitches.

During the surgery, you’ll be asked to focus on a point of light. Staring at this light helps you keep your eye fixed while the laser reshapes your cornea. You may detect a distinct odor as the laser removes your corneal tissue. Some people describe smelling an odor similar to that of burning hair.

If you need LASIK surgery in both eyes, doctors will generally conduct the procedure on the same day

After the procedure

Immediately after surgery, your eye might itch, feel gritty, burn and be watery. You’ll probably have blurred vision. You generally will experience little pain, and you’ll usually recover your vision quickly.

You might be given pain medication or eyedrops to keep you comfortable for several hours after the procedure. Your eye doctor might also ask you to wear a shield over your eye at night until your eye heals.

You’ll be able to see after surgery, but your vision won’t be clear right away. It takes about two to three months after your surgery before your eye heals and your vision stabilizes. Your chances for improved vision are based, in part, on how good your vision was before surgery.

You’ll have a follow-up appointment with your eye doctor one to two days after surgery. He or she will see how your eye is healing and check for any complications. Plan for other follow-up appointments during the first six months after surgery as your doctor recommends.

It might be a few weeks before you can start to use cosmetics around your eyes again. You might also have to wait several weeks before resuming strenuous contact sports, swimming or using hot tubs.

Follow your doctor’s recommendations about how soon you can resume your normal activities.

Results

LASIK often offers improved vision without the hassle of glasses or contact lenses. In general, you have a very good chance of achieving 20/25 vision or better after refractive surgery.

More than 8 out of 10 people who’ve undergone LASIK refractive surgery no longer need to use their glasses or contact lenses for most of their activities.

Your results depend on your specific refractive error and other factors. People with a low grade of nearsightedness tend to have the most success with refractive surgery. People with a high degree of nearsightedness or farsightedness along with astigmatism have less predictable results.

In some cases, the surgery might result in undercorrection. If this happens, you might need another surgery to achieve the proper correction.

Rarely, some people’s eyes slowly return to the level of vision they had before surgery. This might happen due to certain conditions, such as abnormal wound healing, hormonal imbalances or pregnancy. Sometimes this change in vision is due to another eye problem, such as a cataract. Talk with your doctor about any vision changes