Since the late 1970's, incisional refractive surgery (RK) has treated nearsightedness (myopia), farsightedness (hyperopia) and astigmatism in patients all over the world, allowing them to experience a new kind of freedom.  It is the kind of freedom that allows people to make lifestyle choices that were not options to them before because they were totally dependent on glasses or contact lenses.

In 1995, refractive surgery experienced the dawning of a new era with the advent of the Excimer Laser.  Laser in-Situ Keratomileusis or LASIK uses the excimer laser in a surgical process that corrects both eyes and takes less than 30 minutes to perform and can eliminate your dependency on contact lenses and glasses. 

Refractive errors are caused by an imperfectly shaped eyeball, cornea or lens, and are of three basic types:

• myopia — nearsightedness; only nearby objects are clear.
• hyperopia — farsightedness; only objects far away are clear.
• astigmatism — images are blurred at a distance and near.

There's also presbyopia — "aging eye." The condition usually occurs between ages 40 and 50, and can be corrected with bifocals or reading glasses.

To see clearly, the cornea and the lens must bend — or refract — light rays so they focus on the retina — a layer of light-sensing cells that line the back of the eye. The retina converts the light rays into impulses that are sent to the brain, where they are recognized as images. If the light rays don't focus on the retina, the image you see is blurry. This is called a refractive error. Glasses, contacts and refractive surgery attempt to reduce these errors by making light rays focus on the retina.

Laser vision correction was first approved in America by the Food and Drug Administration in November 1995, although, the first laser procedure was performed in Germany back in 1987. To date, there have been over 4 million laser vision procedures performed throughout the world.

PRK (Photorefractive Keratectomy)

Photorefractive keratectomy (PRK) is a procedure performed by the excimer laser. It can be used to correct myopia and/or astigmatism. Drops are placed in the eye to be treated to numb the eye. The patient is then positioned at the laser. The epithelium or outer layer of the cornea is then removed and the laser is used to shape the cornea to correct myopia or astigmatism.

This reshaping of the cornea allows the light rays entering the eye to be focused on the retina, resulting in clearer vision. Since the layer of cornea removed is so thin the cornea is not weakened. Usually one eye is done at a time, as usable vision may not return to normal for several days to several weeks, however occasionally both eyes are done at the same time.

A contact lens is placed on the eye and is left in place until the epithelium heals. This usually takes 3 days. Drops are used to help alleviate the small amount of gritty sensation and tearing that usually occur during this healing phase.

The vision starts to improve once the contact lens has been removed and continues over the next 4 to 6 months. Drops are usually used for 3 to 6 months. It is strongly suggested that one eye be treated at a time. The second eye can be treated once the first eye has achieved a reasonable level of vision. This may take from one week to several months.

Results are excellent with more than 95% of patients achieving an uncorrected vision that is good enough to drive a car. One of the main risks that can affect the results is the possibility of haze development during healing. The risk of this is minimal, but present, particularly in patients with high myopia.

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LASIK (Laser Assisted In-Situ Keratomileusis)

The newest, most advanced Excimer laser procedure is LASIK (Laser Assisted in-Situ Keratomileusis) and is the procedure of choice among refractive surgeons worldwide. LASIK combines the use of an excimer laser with a procedure known as ALK to treat mild to extreme nearsightedness and astigmatism with incredible accuracy and precision. LASIK may also be used to correct farsightedness.

The LASIK procedure is similar to that of PRK. It begins by the ophthalmologist lifting a very thin, outer layer of the cornea (thinner than a contact lens) and gently folding it back. This creates a "protective flap" that stays connected on one side. Then, in seconds, the Excimer laser reshapes the underlying corneal tissue. The protective flap is then replaced to its original position and naturally bonds requiring no stitches. Just as in PRK, this reshaping of the cornea allow light rays to bend or refract onto the retina, allowing for clearer vision. LASIK has proven to provide patients with severe myopia a greater chance for successful results. Both eyes are typically done at the same time as visual recovery is quite rapid.

The procedure takes about 15 minutes to perform. No bandage contact lens is used, but a shield is placed over the eye for the first night. The vision is usually significantly improved during the first 12 - 24 hours and stabilizes with 6 to 12 weeks. Drops are used for one week after the procedure.

No procedure is without risks, but LASIK offers the advantages of more rapid rehabilitation, the possibility for some patients of bilateral treatment, and the greatly diminished risk of haze. Smaller benefits include the reduced irritation that lasts less than 4 hours after the procedure, and reduced risk of infection. Surgeon skill is perhaps more important in this procedure than in PRK.

BENEFITS

The goal of laser vision surgery is to reduce or eliminate the dependence on glasses and contact lenses by improving uncorrected visual acuity. LASIK can allow patients to achieve their normal daily activities without having to use either glasses or contact lenses.

o Nearsighted patients may experience the same level of vision after surgery as they did before surgery without the aid of corrective lenses. The goal again is to eliminate or reduce your reliance on contact lenses and/or eyeglasses.

o Refractive surgery may improve a patient's visual function without the aid of corrective lenses.

o Eyes which are intolerant to contact lenses and/or eyeglasses can be corrected without corrective wear.

Who Benefits Most?

o People with low, moderate and high degrees of nearsightedness

o People with low and moderate degrees of farsightedness

o People with low, moderate and high degrees of astigmatism


Specific Advantages of LASIK

o Effective for correcting a wide range of focusing problems

o Fast visual recovery

o Minimal temporary side effects

o Permanent tissue modification for lasting correction

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IMPRESSIVE RESULTS

In the U.S. clinical trials submitted to the FDA to obtain approval for Laser Vision Correction, 100% of the patients studied experienced improved natural vision or uncorrected vision. Of this, 95% were provided with 20/40 sight or better - the "driving standard" in most states - and were able to enjoy life and perform most activities without contact lenses or glasses. In our practice, the clinical results and patient satisfaction exceed that of the FDA approval data.

Select any of the links below to view graphs displaying results:


Attempted versus Achieved Correction at One Month

Uncorrected VA at 1 Day

UCVA at one month, <-3.5 Diopters

UCVA at one month

Uncorrected VA at 1 Month

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RISKS AND COMPLICATIONS

Undercorrection

There is a tendency for the eye to drift back toward your original prescription. This occurs more commonly in patients with higher amounts of myopia and is called "regression".

This is more common than overcorrection. Slight undercorrection will not seriously affect your vision. In fact, it may be desirable in patients over 40 to help with reading vision. If there's significant undercorrection, a procedure called an enhancement may be performed.

Overcorrection

An initial overcorrection may occur and usually corrects itself in the first month. Overcorrection will make your vision at close range more difficult. After laser vision correction, your distance vision clears first and then your near vision. Overcorrections are rare, about 2% or two of every 1,000 procedures.

Glare and Halos

These are common immediately following the procedure and almost always clear in the first three months. These symptoms usually resolve after the second eye is corrected. Sometimes a weak prescription for night driving may be needed. The incidence of night glare and halos (beyond the early months) is 2%.

While most feared, it is extremely rare. If it does occur, it happens in the first 48 to 72 hours. You will receive antibiotic drops after the procedure to help prevent infection. Infection occurs in less than one-tenth of one percent of the procedures.