This article was provided by AllAboutVision.com. Follow the links below for more information on eye health and vision correction.

Since its introduction in the United States in 1998, many studies have shown LASIK eye surgery is safe and effective. An analysis of more than 3,000 scientific and clinical articles about LASIK published worldwide between 1998 and 2008 that was performed by the American Society of Cataract and Refractive Surgery (ASCRS) found that 95.4 percent of LASIK patients were satisfied with the outcome of their procedure.

Most LASIK complications can be resolved through laser re-treatment or medical treatment. Still, it’s wise to consider the risks of and potential complications of refractive surgery and how to minimize them.

Selecting the right eye surgeon probably is the single most important step you can take to decrease risks associated with LASIK. An experienced, reputable surgeon will make sure you are a good candidate for LASIK before recommending refractive surgery. And if problems develop during or after the procedure, the surgeon should work closely with you to resolve them.

How common are LASIK complications?

Public confidence in LASIK vision correction surgery has grown in recent years because of high success rates involving millions of LASIK procedures performed in the United States and worldwide. With increasingly sophisticated technology used for the procedure, LASIK outcomes are better today than ever.

The U.S. military also has adopted the use of refractive surgery including LASIK to decrease reliance of troops on prescription eyewear. In a study of more than 16,000 U.S. Army personnel who underwent refractive surgery from 2000 through 2003, 86% achieved 20/20 or better uncorrected vision and 98% achieved 20/40 or better (the legal requirement for driving without glasses in most states).

LASIK complication rates

Many experienced LASIK surgeons say serious complication rates can be held well below one percent if surgical candidates are carefully screened prior to surgery. You may be eliminated as a candidate, for example, if you are pregnant or have certain conditions such as diabetes that may affect how well your eyes heal after LASIK. Be sure to discuss any health conditions you have with your eye doctor during your LASIK consultation or pre-operative exam.

An unusually large pupil size can be a risk factor for glare after LASIK, because in dark conditions large pupils might dilate larger than the diameter of the LASIK treatment zone on the front surface of the eye (cornea). Again, make sure you discuss any concerns you have about this or other matters with your eye surgeon before deciding to have LASIK or other laser vision correction surgery.

Other LASIK risk considerations

While the great majority of LASIK outcomes are favorable, some people experience serious and ongoing vision problems after LASIK. No surgical procedure is completely risk-free.

Some LASIK patients with excellent vision based on eye chart testing still can have bothersome side effects. For example, it’s possible a patient may see 20/20 or better without glasses after LASIK but still experience glare or halos around lights at night.

Common LASIK complications

LASIK complications can be caused by a number of factors. The most common complication following LASIK surgery is dry eye.

A study published in the March 2006 issue of American Journal of Ophthalmology found that 36 percent of LASIK patients experienced dry eye symptoms that lasted longer than six months after surgery.

In most cases, post-LASIK dry eye can be successfully treated with prolonged use of artificial tears or use of medicated eye drops to help stimulate natural tear production.

Careful screening of patients for pre-existing dry eye prior to surgery can eliminate many cases of dry eye after LASIK. Often, successful treatment of dry eye prior to LASIK can eliminate or reduce the severity of dry eye symptoms after surgery.

LASIK complications also can be associated with creation of the flap in the cornea, which is the first step of the LASIK procedure. This flap is lifted prior to re-shaping the underlying cornea with an excimer laser, and then is replaced to form a natural bandage.

Flap complications — such as partial flaps, free caps (flaps missing a hinge to keep it attached to the eye), flap wrinkles and displaced flaps — occur infrequently and usually do not cause permanent vision loss.

One large study published in a supplement to the September/October 2005 issue of Journal of Refractive Surgery found the incidence of LASIK flap complications to be 0.24 percent. Another study published in the April 2006 issue of American Journal of Ophthalmology found that flap complications occurred in 0.3 to 5.7 percent of LASIK procedures.

In most cases, flap complications are resolved by lifting and repositioning the flap. Sometimes, a bandage contact lens may be applied over the flap for a few days to help the flap stay properly positioned while it heals and adheres to the underlying cornea.

Use of a femtosecond laser rather than a mechanical surgical tool (called a microkeratome) appears to reduce the risk of some flap complications.

Other LASIK complications include: 

• Significant Undercorrection, Overcorrection or Regression: An overcorrection or undercorrection of your refractive error (nearsightedness, farsightedness and/or astigmatism) can cause your vision to remain noticeably blurred after LASIK. Also, sometimes your vision can be corrected perfectly by LASIK surgery, but then some of your refractive error returns (this is called regression).

Usually, undercorrection, overcorrection and regression can be successfully treated with an additional laser treatment (called an enhancement). Enhancement surgeries typically are performed at least three months after the initial LASIK procedure to make sure your vision is stable. A study published in the April 2003 issue of Ophthalmology found that nearly 18 percent of LASIK patients (12 percent of treated eyes) needed an enhancement procedure. 

• Diffuse Lamellar Keratitis: This condition (also called DLK), is inflammation under the LASIK flap associated with the accumulation of white blood cells. One study published in the Journal of Refractive Surgery in 2005, found the incidence of diffuse lamellar keratitis after LASIK surgery to be 2.3 percent. DLK usually can be successfully treated with steroid eye drops, but sometimes the eye surgeon might have to lift the flap and manually remove the accumulated inflammatory cells.
• Eye Infection or Irritation: Eye infections can occur after LASIK, but they are rare. To reduce the risk of post-LASIK eye infections, your eye doctor will prescribe antibiotic eye drops for you to use for several days after surgery.

Vision changes unrelated to LASIK

If you have LASIK in your 20s or 30s, be aware that your reading vision will change as you get older. This has nothing to do with your LASIK surgery – it’s caused by a normal age-related loss of focusing ability called presbyopia.

Because of presbyopia, most LASIK patients (like anyone else who sees well without glasses in younger years) will need reading glasses in middle age.

Article ©2011 Access Media Group LLC. All rights reserved. Reproduction other than for one-time personal use is strictly prohibited.

This article was provided by AllAboutVision.com. Follow the links below for more information on eye health and vision correction.

Photorefractive keratectomy (commonly called PRK) is the original laser vision correction procedure. PRK received FDA approval for use in the United States in 1995, a few years before LASIK.

Though LASIK has surpassed PRK as the most popular vision correction surgery, PRK remains a very viable procedure for the correction of nearsightedness, farsightedness and astigmatism.

Comparing PRK and LASIK

In both PRK and LASIK, the eye surgeon uses an excimer laser to reshape the cornea and correct refractive errors (nearsightedness, farsightedness and/or astigmatism). The difference between the two procedures is what happens before the laser treatment.

In PRK, only the clear outer layer of the cornea (epithelium) is removed prior to the laser reshaping. This epithelium generally grows back within a few days after surgery.

In LASIK, a corneal flap containing both the epithelium and underlying corneal tissue (stroma) is created. The flap remains attached to the eye by a small hinge and is replaced after the excimer laser treatment. The flap acts like a living bandage, and enables faster vision recovery after surgery. It also reduces post-operative discomfort while the eye is healing.

Though LASIK is more popular than PRK because of these features, PRK has its own distinct advantages. Because no corneal flap is created during PRK, there is no risk of a flap complication after surgery. Also, PRK often can be performed on corneas that may be too thin for LASIK surgery.

Many studies have shown that the long-term visual outcomes of PRK and LASIK are essentially the same.

Before PRK Surgery

Prior to PRK surgery, your eye doctor will evaluate the health of your eyes and determine exactly what kind of vision correction you need.

An instrument called a corneal topographer may be used to create a “map” of your cornea that displays the curvature of your eye and irregularities that the surgeon must address. Also, wavefront-guided measurements that are used for custom LASIK may be used to create a PRK treatment that reduces higher-order aberrations for optimum visual acuity.

Your eye doctor will ask you about any medical conditions you have. Some conditions may disqualify you as a candidate for laser vision correction; others may mean a postponement of the procedure or the need for special care afterward.

During PRK Surgery

PRK, like LASIK, is an outpatient procedure and takes only takes a few minutes per eye. However, expect to be at the surgical center for at least an hour.

The basic steps in PRK surgery are:

1. Anesthetic eye drops are applied to your eye to prevent discomfort during the procedure.
2. A device is placed under the eyelids to keep your eye wide open.
3. The central epithelium is removed — either manually (after being softened with a dilute alcohol solution) or with a laser.
4. The excimer laser is positioned over your eye and activated to reshape the cornea.

After the laser treatment is finished, medicated eye drops are applied to your eye to prevent infection and reduce inflammation. A soft contact lens is applied to your eye to serve as a bandage during the initial healing period after surgery.

Your eye doctor also will prescribe medication to control any post-operative pain, but many people feel no more than mild discomfort or “scratchiness” afterward.

After PRK

Immediately after PRK, you will rest for a little while. Unlike LASIK, which nearly always is performed on both eyes the same day, PRK usually is performed on each eye separately, about a week or two apart. This allows time for the first eye to heal and attain good vision before the second eye is treated.

You can go home shortly after the procedure, but someone else must drive. At home, you should relax and rest your eyes for at least a few hours.

As with any kind of eye surgery, it’s important that you follow your doctor’s instructions to the letter. Get plenty of rest and call your eye doctor immediately if you suspect a problem anytime after your PRK surgery.

You may be able to go to work the next day, but many doctors recommend a couple days of rest after PRK surgery . You also should avoid strenuous exercise for up to a week.

Two or three days after surgery, after the epithelium has had a chance to grow back, the bandage contact lens is removed. Typically, you will continue to use anti-inflammatory medications for several weeks after surgery.

Visual Outcomes After PRK

Most people see 20/20 or better after PRK, as clearly as they would after LASIK.

But vision recovery takes longer after PRK, and it may be three to six months before optimum visual acuity is attained. In some cases, prescription glasses may be needed temporarily until your vision improves sufficiently after PRK.

If you are over age 40, it is likely you will still need to wear reading glasses after PRK.

PRK Risks and Complications

As with LASIK, there are risks and potential complications associated with PRK. Possible complications after PRK include:

• Dry eyes
• Glare, starbursts and/or halos when driving at night
• Eye infection or inflammation
• Incomplete or inaccurate vision correction

Serious complications during and after PRK are rare; and you can decrease your risk of problems by carefully following your eye doctor’s instructions before, during and after surgery.

Article ©2011 Access Media Group LLC. All rights reserved. Reproduction other than for one-time personal use is strictly prohibited.

This article was provided by AllAboutVision.com. Follow the links below for more information on eye health and vision correction.

Laser eye surgery isn’t for everyone. Here are a few guidelines to help you decide if LASIK is right for you:

• Are you an adult? You need to be at least 18 years of age to have LASIK. (Younger patients can sometimes be treated as an exception. Discuss this with your surgeon.)

• Are your eyes healthy? If you have any condition that can affect how your eyes respond to surgery or heal afterwards, wait until that condition is resolved. Examples include chronic dry eyes, conjunctivitis (“pink eye”) and any eye injury. Some conditions, such as cataracts, keratoconus and uncontrolled glaucoma, may disqualify you completely.
  
• Is your vision stable? If your prescription for eyeglasses or contact lenses is still changing year-to-year, you are not a good candidate for LASIK. Make sure your prescription is stable for a 12-month period before having LASIK. Otherwise it’s possible your eyes will continue to change after surgery and you again will need glasses or another LASIK procedure to improve your eyesight.

• Are you pregnant? Hormonal changes during pregnancy can cause swelling in your corneas, changing your vision. Dry eyes are also common when you’re pregnant. Also, eye medications (antibiotics and steroids) used during and after LASIK may be risky for your baby, whether unborn or nursing. Wait a few months after your baby is born before having LASIK.

• Do you have any systemic and autoimmune disease? Problems like rheumatoid arthritis, diabetes, HIV and AIDS can increase the risk that your eyes might not heal properly after LASIK. Professional opinions vary regarding which diseases are automatic disqualifiers and which ones might pose acceptable LASIK risks. Ask your eye surgeon for details.
  
• Do you have very high amounts of nearsightedness or farsightedness? LASIK works best for mild to moderate amounts of myopia. If you are very nearsighted, it’s possible that too much corneal tissue would have to be removed during LASIK to correct your vision, which could put you at risk for serious LASIK complications. In such cases, an alternative refractive procedure such as phakic IOL implantation or refractive lens exchange might be a safer option and produce better outcomes.

Your eye surgeon will discuss these and other selection criteria with you at your LASIK consultation.

Article ©2011 Access Media Group LLC. All rights reserved. Reproduction other than for one-time personal use is strictly prohibited.

This article was provided by AllAboutVision.com. Follow the links below for more information on eye health and vision correction.

LASIK (laser-assisted in situ keratomileusis) currently is the most popular type of vision correction surgery available today. Since it was first introduced in America in 1998, several million LASIK procedures have been performed in the United States.

LASIK has quickly become popular because the procedure takes only a few minutes per eye, there is little or no discomfort during or after surgery, and many patients see 20/20 without glasses within hours after the procedure.

LASIK can correct nearsightedness, farsightedness and astigmatism. With a special technique called monovision, it also can reduce the need for reading glasses among patients over age 40 who wear bifocals.

Am I a good candidate for LASIK?

To be a good candidate for LASIK, you should be at least 18 years old, have healthy eyes, and have adequate corneal thickness for the procedure.

Chronic dry eye problems, corneal diseases and other abnormalities may disqualify you from having LASIK surgery. In order to know for sure if you are a good candidate, a comprehensive eye exam is required.

It also is important for you to have realistic expectations regarding the quality of your vision after LASIK surgery and be willing to accept a less-than-perfect outcome.

A recent analysis of more than 3,000 scientific and clinical studies published worldwide revealed that 95.4 percent of LASIK patients were satisfied with the outcome of their surgery. But there are no guarantees, and LASIK doesn’t always create perfect vision. In some cases, your vision after LASIK may be permanently less clear than it was with glasses before the procedure. You have to ask yourself if you’re willing to accept the risk of such an outcome before you decide to have LASIK surgery.

It is important to remember that LASIK is an elective procedure, not a medically necessary one, when evaluating risk and potential complications.

The LASIK procedure

LASIK is an outpatient procedure and generally takes less than 15 minutes for both eyes, but expect to be at the surgery center for an hour or more.

It is a two-step procedure: In the first step, the surgeon uses a femtosecond laser or a bladed instrument called a microkeratome to create a thin flap of tissue on the clear front surface of your eye (cornea). This flap is folded back and an excimer laser is used to reshape the underlying corneal tissue to improve vision. After this laser treatment, which usually takes less than a minute, the flap is repositioned and the surgeon moves on to your other eye. 

Wavefront LASIK

Wavefront LASIK (also called wavefront-guided LASIK or custom LASIK) is an advanced form of LASIK where a computerized instrument creates a detailed map of the power of your eye to guide the excimer laser. Wavefront-guided procedures are more precise than conventional LASIK treatments that are based only on an eyeglasses prescription, and they can correct subtle optical imperfections of the eye called “higher-order aberrations” that cannot be treatd with conventional LASIK. Several studies show wavefront-guided ablations provide sharper vision than conventional, non-wavefront LASIK and may reduce the risk of nighttime glare and halos.

After LASIK surgery

After LASIK, your surgeon or an assistant will apply medicated eye drops and clear protective shields over your eyes. You can open your eyes and see well enough to walk without glasses, but you must have someone drive you home.

You will be expected to use medicated eye drops several times a day for a week or so to protect your eyes from infection and help them heal properly. You also will be told to use artificial tears frequently to keep your eyes moist and comfortable.

You should rest and not use your eyes much when you return home on surgery day. You also may be more comfortable if the lights in your house are dimmed.

The following day, you should be seeing well enough to drive and can resume most activities. Be careful, however, not to rub your eyes until your eye doctor tells you it is safe to do so.

Usually, you will be asked to return to the surgery center the following day so your surgeon or another eye doctor at the center can check your vision and make sure your eyes appear as they should. At this visit, you typically will be given additional instructions about using eye drops and artificial tears, and you will be able to ask the doctor any questions you have.

An eye doctor other than your LASIK surgeon might perform your post-operative care in an arrangement called co-management. If this is the case, the doctor performing your care after surgery will alert your surgeon if any complications arise that require the surgeon’s attention.

What if my vision is still blurry after LASIK?

Though most patients see quite clearly in a matter of days after LASIK, it can take several months before your eyes are completely stable. Until then, improvements in your vision can still occur. But if several months pass and your vision remains unclear, see your LASIK surgeon. In some cases, and additional LASIK surgery (called an enhancement) is needed to sharpen your eyesight further.

If for some reason an enhancement is not indicated or desired, it may be beneficial for you to wear eyeglasses or contact lenses for certain activities.

Eyewear after LASIK

Keep in mind that, even if your vision seems perfect after LASIK, you still need eyewear.

When outdoors, it’s important to wear sunglasses that provide 100 percent protection from the sun’s harmful ultraviolet (UV) rays. Overexposure to UV radiation over the course of many years has been associated with eye problems such as cataracts and macular degeneration.

If you play sports when wearing sunglasses, make sure the lenses are made of impact-resistant polycarbonate for extra protection. And any time you’re working with power tools or doing anything else when an eye injury is possible, you should wear safety glasses with polycarbonate lenses.

If you’re over age 40 (or soon will be), it’s likely you’ll need reading glasses after LASIK. Also, many LASIK patients benefit from a pair of prescription eyeglasses for night driving. Though these lenses may have only a mild prescription, they often can make your vision sharper for added safety and comfort.

Eye care after LASIK

Don’t forget to continue to have routine eye exams after LASIK. Even if your vision is perfect, you still need to have your eyes checked for glaucoma and other potential problems on a regular basis.

Routine exams also help you make sure your vision remains stable after LASIK.

Article ©2011 Access Media Group LLC. All rights reserved. Reproduction other than for one-time personal use is strictly prohibited.

This article was provided by AllAboutVision.com. Follow the links below for more information on eye health and vision correction.

Are you tired of wearing glasses or contact lenses? Today, there are several types of vision correction surgery that can improve your eyesight and help you see clearly with prescription eyewear.

LASIK is the most popular vision-correcting or “refractive” surgery and has been performed in the United States since 1998.

LASIK (laser-assisted in situ keratomileusis) is a two-step procedure: First, a thin flap is created on the clear front surface of the eye (cornea) with a femtosecond laser or a bladed surgical instrument called a microkeratome. This flap is folded back and the underlying cornea tissue is reshaped with an excimer laser.

After the laser treatment, the flap is repositioned and heals without the need for stitches. The entire surgery takes only a few minutes per eye.

One of the primary reasons for the popularity of LASIK is that there is little or no discomfort after the procedure, and vision usually is quite clear within minutes.

But there are other refractive surgery options to correct your vision if you are not a good candidate for LASIK or if you and your eye doctor feel a different procedure better suits your needs. Here are a few alternatives:

PRK

PRK (photorefractive keratectomy) was the first laser vision correction procedure approved in the United States, receiving FDA approval in 1995. Because of its superior predictability, PRK soon replaced radial keratotomy (RK), which was the only viable surgical treatment for nearsightedness available at the time. PRK reduced many of the complications of RK, including fluctuating vision, glare, halos around lights, infection, unpredictable outcomes, decreased visual acuity and regression (return of nearsightedness).

Like LASIK, PRK uses an excimer laser to reshape the cornea and correct vision. But with PRK, the laser treatment is applied directly to the surface of the eye, rather than under a flap of corneal tissue.

Visual outcomes of PRK are comparable to those of LASIK and other laser vision correction procedures. But recovery time after PRK is longer than after LASIK. Since no corneal flap is created in PRK, the thin outer protective layer of the cornea (the epithelium) must grow back after surgery, which can take several days. Until this process is complete, there is some discomfort after PRK for a few days and vision can be quite blurred for a week or two until the eye heals.

The number of PRK procedures declined sharply when LASIK was introduced, because there is usually little or no discomfort after LASIK and vision recovers faster. However, PRK has made a comeback in recent years due to more effective pain management techniques and because it poses less risk of certain complications.

LASEK

LASEK (laser-assisted sub-epithelial keratomileusis) is a modification of LASIK in which the corneal flap is thinner, containing only epithelial cells. The delicate epithelium is removed by loosening it from the underlying cornea with an alcohol solution. It’s then pushed to the side and the laser treatment is applied. The epithelial “flap” is then gently replaced and covered with a bandage contact lens until it reattaches to the underlying cornea.

In many cases, there is less post-operative discomfort with LASEK compared with PRK, and vision recovery may be faster. LASEK sometimes is preferred over LASIK in cases when the patient’s cornea is considered too thin for a safe LASIK procedure.

Epi-LASIK

Epi-LASIK is much like LASEK, except a special cutting tool is used to separate the epithelium from the underlying cornea prior to the laser treatment. This eliminates the possibility of an adverse reaction to alcohol placed on the eye and may speed healing after surgery, compared with LASEK. Like LASEK, epi-LASIK sometimes is preferred over LASIK if there are concerns about corneal thickness.

IntraLASIK, iLASIK

IntraLASIK and iLASIK are terms sometimes used to describe a LASIK procedure when the corneal flap is created with a femtosecond laser instead of a microkeratome for blade-free, all-laser surgery. All-laser LASIK eliminates the risk of certain complications that can occur when the flap is created with a microkeratome.

Wavefront LASIK

Wavefront LASIK (also called wavefront-guided LASIK or custom LASIK) is an advanced type of LASIK where the laser treatment is determined by a computerized mapping of the power of the eye called wavefront analysis. Wavefront-guided procedures are more precise than ablations determined by using only an eyeglasses prescription, and they can correct subtle optical imperfections called “higher-order aberrations” (HOA) that regular (non-wavefront) LASIK can’t treat. Several studies show wavefront-guided LASIK produces sharper vision than conventional LASIK and may reduce the risk of post-LASIK glare and halos.

Another advanced type of LASIK is wavefront-optimized LASIK, which is designed to reduce a specific type of HOA called spherical aberration. Some studies have found that wavefront-optimized LASIK produces visual outcomes that are equal to wavefront-guided LASIK.

Wavefront technology (both wavefront-guided and wavefront-optimized) can also be used for PRK and other laser vision correction procedures.

Conductive keratoplasty

Conductive keratoplasty (CK) is a non-laser refractive surgery that uses a hand-held instrument to deliver low-heat radio waves to a number of spots in the peripheral cornea. This causes the corneal tissue to shrink in these areas, which increases the curvature of the cornea, thereby correcting mild amounts of farsightedness or restoring usable near vision to people over age 40 who have presbyopia.

CK for presbyopia is called NearVision CK, and it can be used to correct presbyopia for people who previously had LASIK surgery.

Phakic IOLs

Phakic IOLs (intraocular lenses) are small lenses implanted inside the eye to correct vision problems. The lenses can be place in front of the pupil (attached to the front of the iris) or behind it. “Phakic” refers to the fact that the eye’s natural lens remains in the eye during the procedure.

Phakic IOL implantation can correct higher amounts of nearsightedness than LASIK. But because it’s an internal eye procedure, there are more risks associated with phakic IOL surgery than with LASIK. Cost of the procedure also is significantly higher.

Refractive Lens Exchange

Refractive Lens Exchange (RLE) is another non-laser, internal eye procedure. RLE is much like cataract surgery, but instead of removing the eye’s natural lens that has grown cloudy, the surgeon removes a clear natural lens and replaces it with an artificial lens of a different shape to reduce the need for glasses.

RLE has a higher risk of complications and is more expensive than LASIK. It usually is recommended only for cases of severe vision correction needs or for patients who are at risk of cataracts and already are presbyopic. In some cases, multifocal or accommodating IOLs (see below) are used in RLE to reduce the need for reading glasses after surgery.

Cataract Surgery

Even cataract surgery can be considered a refractive procedure. New intraocular lenses (IOLs) implanted during cataract surgery can partially restore a person’s near vision in addition to correcting nearsightedness and farsightedness. These lenses — called multifocal IOLs or accommodating IOLs —currently are being used by many cataract surgeons and are producing excellent results.

While Medicare and health insurance usually will cover the basic costs of cataract surgery, choosing multifocal or accommodating IOLs that potentially can restore a full range of vision will increase your cataract surgery cost, and you will be responsible for paying the added cost of these premium lenses.

Which procedure is right for you?

If you are interested in LASIK or other vision correction surgery, your first step is to schedule a comprehensive eye exam and refractive surgery consultation. During this visit, your eye doctor will determine if you are a good candidate for refractive surgery and discuss which procedure might be best for your needs.

If you are a good candidate, your eye doctor can help you choose an experienced refractive surgeon in your area for your vision correction surgery.

Article ©2011 Access Media Group LLC. All rights reserved. Reproduction other than for one-time personal use is strictly prohibited.