Photorefractive keratectomy (PRK). With PRK, rather than forming a flap, the top surface, called the epithelium, is removed. This corneal abrasion takes 3 to 4 days to heal, resulting in mild to moderate pain and blurred vision in the short term. Visual recovery takes longer in PRK than it does with LASIK.

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LASIK surgery has a good track record. Complications are rare, and most people are satisfied with the results. Certain side effects, particularly dry eyes and temporary visual issues (such as glare), are fairly common. These usually clear up after a few weeks or months, though some people consider them to be a long-term problem.

In LASIK, the surgeon creates a flap in the cornea and then raises it up before reshaping the cornea. There are other types of laser refractive surgery that may not use a flap. Each technique has advantages and disadvantages.

When it comes to LASIK eye surgery, there are no right answers. Carefully consider the factors outlined here, weigh your preferences and risk tolerance, and make sure you have realistic expectations. Talk to an eye surgeon in whom you feel confident and get your questions answered. In the end, if it feels right, then proceed, but if it doesn't, don't rush into anything.

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This is usually not an issue, but know that you'll have to completely stop wearing your contact lenses and switch to glasses for at least a few weeks before your surgery. Contact lenses distort the natural shape of your cornea. This can lead to inaccurate measurements and a less than optimal surgical outcome. Your doctor will provide specific guidelines depending on your situation and how long you've been a contact lens wearer.

Most insurance plans consider laser eye surgery to be an elective procedure and don't cover the cost. Know what the surgery will cost you.

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In general, laser eye surgery is most appropriate for people who have a moderate degree of refractive error and no unusual vision problems.

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Before a LASIK procedure, your eye surgeon will take detailed measurements of your eye and check the overall health of the eye. You may be told to take a mild sedative medication just before the procedure. However, this is not common. After you are lying comfortably on an operating table, eye-numbing drops will be administered. Then your surgeon will use a special type of cutting laser to precisely sculpt the curvature of your cornea. With each pulse of the laser beam, a tiny amount of corneal tissue is removed. This allows your eye surgeon to flatten the curve of your cornea or make it steeper.

It was thought that these drawbacks were outweighed by the theoretical advantage that PRK was safer for people who are more likely to be struck in the eye — for example, those involved in contact sports, law enforcement or the military. But even with standard LASIK, the risk of cornea flap dislocation is still very low, so there is probably no significant advantage with PRK. PRK may be a better procedure for those with thin corneas.

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Typically, images are focused on the retina in the back of the eye. With nearsightedness, farsightedness or astigmatism, images are focused either in front of or behind the retina. This results in blurred vision.

If you're tired of wearing eyeglasses or contact lenses, you may wonder whether LASIK surgery is right for you. LASIK is a type of refractive eye surgery.

There are several types of laser refractive surgery. LASIK is the best known and most commonly performed. Many articles, including this one, will use the term "LASIK" to refer to all types of laser eye surgery.

Most people report high satisfaction after LASIK surgery. But long-term results often aren't available or haven't been well studied. Part of the reason for this is that people are overall satisfied after surgery, so they don't feel a need for repeat examinations and follow-up data is not collected. Also, the LASIK procedure has been refined over time — the techniques and technology are continually changing. This makes it difficult to draw conclusions from the data that is reported.

Talk with your eye surgeon about your questions and concerns and how LASIK will benefit you. The surgeon can help you understand the benefits and limitations of surgery.

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Individual eye surgeons may specialize in specific types of laser eye procedures. The differences among them are generally minor, and none are clearly better than any others. Some surgeons feel creating a flap in LASIK poses a slightly higher risk compared to procedures that don't involve a flap. Depending on your circumstances and preferences, you may consider:

Intraocular lenses. Corrective lenses can be surgically inserted in the eye to improve vision. These intraocular lenses are routinely done as part of cataract surgery (in which the old, cloudy natural lens is removed). Intraocular lenses also may be an alternative to LASIK for older adults who may need cataract surgery in the future.

Certain conditions and medicines — pregnancy, breastfeeding, steroid drugs — may cause temporary changes in your vision. Wait until your vision has stabilized before considering LASIK eye surgery.

By their early to mid-40s, all adults lose some ability to focus on nearby objects. This condition is called presbyopia. Presbyopia results in difficulty reading small print or doing close-up tasks.

In general, most people who have laser-assisted in situ keratomileusis (LASIK) eye surgery achieve 20/20 vision or better, which works well for most activities. But most people still eventually need glasses for driving at night or reading as they get older.

Your eye surgeon will also ask detailed questions about your general health. Certain medical conditions, unrelated to your eyes, can increase the risks associated with LASIK surgery or make the outcome less predictable. These include:

If you are an older adult considering LASIK, you might choose to have monovision to maintain your ability to see objects close up. With monovision, one eye is corrected for distant vision, and the other eye is corrected for near vision. Not everyone is able to adjust to or tolerate monovision. It's best to do a trial with contact lenses before having a permanent surgical procedure.

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Your eye surgeon will probably work with a team, who may help with your initial evaluation and measurements. But it is your surgeon who takes the ultimate responsibility for determining whether LASIK is an appropriate choice for you, who confirms the measurements to guide the procedure, who performs the procedure and who provides postoperative care.

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Over time, your refraction may slowly worsen with age and your vision may not be quite as good as it was immediately after surgery. This is called regression. This does not seem to be a large problem, but the exact degree of change to be expected is sometimes unpredictable.

Younger people with high degrees of nearsightedness that cannot be satisfactorily treated with corrective lenses also may be offered intraocular lenses. But these are not a routine option for most people.

Most people don't have firsthand knowledge about LASIK or an eye surgeon. A good starting point when choosing an eye surgeon is to talk with the eye professional you know and trust. Or ask friends or family members who have had successful LASIK.

Your results depend on your refractive error and other factors. People with mild 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.

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LASIK eye surgery may mean no more corrective lenses. But it's not right for everybody. Learn whether you're a good candidate and what to consider as you weigh your decision.

Traditionally, blurry vision is corrected by bending (refracting) light rays with glasses or contact lenses. But reshaping the cornea itself also can provide the necessary refraction and vision correction. The cornea is the dome-shaped transparent tissue at the front of your eye.

Complications that result in a loss of vision are rare. However, certain side effects, including dry eyes and temporary visual changes, are fairly common. But these usually resolve after a few weeks or months, and very few people consider them to be a long-term problem.

Your eye surgeon will ask detailed questions about your eye health. The surgeon also will evaluate your eyes to make sure you don't have any conditions that might result in complications or poor outcomes of surgery. These include:

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Keep in mind that even when postoperative follow-up is done and reported, vision is measured under optimal testing conditions. Your vision in dim light (such as at dusk or in fog) may not be as good as published reports suggest it will be.

Most people who undergo LASIK surgery will have good to excellent vision in most situations, for many years or decades. You'll be able to play sports and swim, or even just see the clock first thing in the morning, without having to worry about your glasses or contact lenses. But as you get older or in low-light conditions, you may still need to wear glasses.

If you have myopia, your vision may continue to change throughout your teenage years, or even longer. This may require occasional changes in the prescription of your glasses or contact lenses. Therefore, people should be over age 18, and preferably older, before considering LASIK eye surgery.

One possible benefit of having been nearsighted most of your life is that this condition actually compensates for the presbyopia that inevitably develops as you get older. A nearsighted eye will focus on near objects by itself without reading glasses. LASIK surgery removes this near focus because the nearsightedness has been corrected. This means that as you get older you will need to use reading glasses. Many people are happy to trade clear distance vision when they are younger for having to wear "cheaters" for reading when they are older.