Although Laser Vision Correction (LVC) can be offered to most individuals there are some important guidelines. LVC is available to patients who are at least 21 years old and whose eyeglass prescription has stopped changing. Treatments are available for low to high degrees of myopia, low to moderate hyperopia, low to moderate astigmatism or astigmatism with myopia, hyperopia, or both (mixed astigmatism). Based on spectacle correction only, it is estimated that over 90% of individuals requiring glasses for distance vision could be candidates. Your eyes should generally be healthy although eyes with certain minimal problems may still be eligible. It is important to tell your doctor about any eye conditions or general health problems and about any medications you use. In some situations, LVC should not be done. Individuals with vascular disease, autoimmune disease (rheumatoid arthritis, lupus) or corneal deformity (keratoconus) are not candidates. Women must avoid LVC during pregnancy. Patients who form excessive scar tissue (keloids) or have had herpes virus infections of the eye are not LVC candidates. Patients are not eligible for LVC while on certain medications including Accutane, steroids, Cordarone or Imitrex.

LVC is an elective procedure, the alternative being glasses, contact lenses orthokeratology or other refractive surgical procedures such as Intacs or Conductive keratoplasty (CK).

How the Excimer Laser Works
The excimer laser produces an invisible ultraviolet light that was originally developed etch computer microchips. This laser light was subsequently found to be uniquely suited for corneal reshaping. Each pulse of the laser removes a microscopic shaving of corneal tissue. The excimer is said to be "cool" because unlike other types of lasers it does not produce heat that could damage delicate eye structures. A computer precisely controls the pattern and number of pulses applied sculpting the cornea into shape. This reshaping of cornea changes its focusing power so that images are sharply focused on the retina.

The exact pattern of pulses delivered to the cornea will determine the type of correction performed (i.e. for nearsightedness farsightedness, or astigmatism). In addition, the lasers used have the ability to identify the center of the cornea and to track its movements so that the laser can move if the eye moves. This assures a more precise application of the sculpting energy to the area exactly over the pupil. In addition, new technology is becoming available that will permit true custom corneal treatments. Special imaging devices called Wave Scan Analyzers are able to create a detailed map of the entire focusing system of the eye and identify even microscopic abnormalities in the way the eye focuses. This information can then be transferred directly to the laser so that the laser can truly customize a treatment for each individual eye. This technology is now available for some types of vision problems and more applications will be available in the future.

Pre-Treatment Evaluation
An initial screening eye exam is required to determine if you are a candidate for laser vision correction. Your nearsightedness needs to be stable for at least one year. Old glasses or prior eyeglass prescriptions can establish this. Contact lens may alter an individual's prescription and must be removed prior to the exam (three weeks for gas permeable lenses and one week for soft lenses). Candidates will then have a comprehensive eye examination to determine the exact treatment plan. This will include a computerized mapping of the corneal surface.

LASIK (laser in situ keratomileusis) is a recent development in a family of procedures known as lamellar refractive surgery. The goal of these operations is to modify the front curvature of the cornea so that light will be properly refracted or focused to achieve a sharp image on the retina. With these surgeries a thin flap of the cornea is lifted using a microkeratome which glides across the cornea like a miniature carpenters plane. Earlier operations such as keratomileusis or ALK (automated lamellar keratoplasty) created the desired reshaping of the cornea by freezing & lathing the flap or cutting it again with the microkeratome. While effective these operations lacked the precision required for excellent vision in a high percentage of patients. The FDA approval of the excimer made it possible to combine the long established microkeratome techniques with the precise corneal re-shaping of the laser. Thus the LASIK technique was created.

How LASIK Works
The microkeratome is placed on the eye while the patient is comfortably reclined under the excimer laser.

The sculpting of the cornea imparts a new curvature to its front surface thus altering the focal point of the eye to produce a sharp image on the retina. The entire process is completed in 15 - 20 minutes.

Who Can Have LASIK?
LASIK may be used for a fairly wide range of corrections. The FDA has approved the use of an excimer laser in the LASIK procedure to correct low to high degrees of myopia, low to moderate hyperopia, and low to moderate astigmatism. In general patients should be healthy and free of other eye abnormalities. Patients should be at least 21 with a documented stable refraction. Exclusions are listed below:

· corneal diseases including keratoconus or herpes infection of the eye
· vascular illness (i.e. diabetes)
· auto-immune disease (i.e. lupus, rheumatoid arthritis)
· pregnancy
· patients who form excessive scar tissue (keloids)
· patients taking certain medications such as Accutane, Cordarone or Imitrex.
· immunodeficiency

Results with LASIK
The majority of patients who have LASIK are able to achieve unaided vision between 20/20 and 20/40. This is functional vision for most people, permitting all usual activities such as sports, watching television or movies and driving. The initial vision recovery is rapid with much of the improvement already apparent on the first day after the procedure. Some slight fluctuations in vision can take place in the first few weeks. For most patients the results have completely stabilized by three months.

As with any operation unwanted side effects can occur. Either over corrections or under corrections are occasionally encountered. In such cases the unaided vision may be somewhat blurry but corrective lenses permit sharp vision. Often a retreatment may be performed to improve the vision. This is generally done after three months to allow for the initial correction to stabilize. Other complications may affect the vision causing it to be blurred even with corrective lenses. Corneal haze associated with healing is rarely seen in LASIK. However vision may be affected if the flap is damaged. This could occur as an intraoperative problem with the microkeratome or post-op as a result of injury or excessive eye rubbing. It is also possible for particles to become trapped under the flap or for epithelium (the surface "skin" of the cornea) to grow under the flap. In the event of a flap problem it may be necessary to perform additional corrective procedures. Fortunately visually significant flap problems are uncommon. Corneal infections or inflammation are rare but can occur. They are usually successfully treated with antibiotic or steroid eye drops.

Pre - Treatment Evaluation
Prior to the procedure a comprehensive eye exam will be required. Contact lenses can alter the measured prescription for the eye. Therefore they must be removed prior to the exam as follows: one week for soft lenses and three weeks for rigid gas permeable lenses. It is important not to operate on an eye if the prescription is still changing. Bringing old glasses or prescriptions to the exam will help determine if the eyes are stable. A detailed eye exam will be conducted and a computerized map of the eye surface will be generated to screen for any irregularities. A detailed explanation of the risks and benefits of the procedure will be given. Procedures can usually be scheduled within one to two weeks after the exam.

LASIK Treatment
Treatments are performed on an outpatient basis. You should bring a companion to assist your trip home. The eye will be numbed with drops and a mild sedative will be given by mouth.

The desired correction is programmed into the laser computer before your arrival into the laser suite. A small speculum is inserted into the eye to prevent blinking. The laser microscope is aligned over the eye and a ring is placed around the eye for stabilization. The microkeratome is then passed across the cornea and the flap is raised. The flap is then held to one side and the patient is asked to look at a fixation light. The laser is recentered and the laser sculpting begins. Upon completion the eye is irrigated to remove any particles and the flap is repositioned. Antibiotic drops are instilled and the eye is either patched or covered with a clear bandage contact lens. The time in the laser suite is typically 15 - 20 minutes and the laser sculpting takes 45 -60 seconds.

Post - Treatment
You will be seen in the office the day after the procedure. It is normal to have some foreign body sensation, tearing, and light sensitivity at this time. Most patients report the overall level of discomfort to be mild. An antibiotic and anti-inflammatory eye drop will be started on the first post-op day and continued for one to two weeks. The unaided vision will be markedly improved even on the first day. Steady improvement takes place during the next week although some fluctuations may occur for a few weeks. Stabilization is usually achieved by three months.

It is normal to be slightly overcorrected in the first week or two. For nearsighted corrections, this creates a temporary farsightedness, which may make reading difficult especially for those over age 40. For farsighted corrections the effect is temporary nearsightedness, which facilitates reading but blurs distance slightly. Some people experience glare or halos around lights at night. If present this usually diminishes as the eye heals. Some degree of glare may persist and is similar to that experienced with contact lenses. Some degree of dryness may also occur, requiring the use of artificial tears, or the placement of plugs in the tear ducts to retain natural moisture.
Healing will be carefully monitored during the post-op period. It is important to keep all scheduled visits and follow any directions regarding medications.

To read LASIK commonly asked questions, click here.

PRK is the first of the excimer techniques to be developed, and follow-up for the earliest cases now reaches 15 years. Overall outcomes have been excellent with few complications, and demonstrated long-term stability. The improvement in vision is similar to that for LASIK over a wide range of corrections.

Excimer Treatment
Treatments are performed on an out patient basis. You will need to bring a companion to assist you in your return home. Drops to numb the eyes will be administered and you may be given a mild sedative by mouth. Your prescription will be programmed into the computer, which directs the laser to deliver the correct pattern of pulses. The surgeon aligns the eye under the laser's microscope and removes the epithelium (the protective outer "skin" of the cornea). The laser tracks the position of the eye so that the laser pulses will be delivered to the exact area desired. The laser than sculpts the cornea to its new shape in a process typically requiring 30 to 45 seconds. Antibiotic drops will be placed on the eye. In most cases a clear bandage contact lens will be placed to protect the eye while the epithelium heals. Occasionally, however a patch will be required. Some discomfort or foreign body sensation is expected in the first 24 to 36 hours along with light sensitivity and tearing. Most individuals can return to work on the second day following the PRK. Prescription pain medications may be used as needed.

Post Treatment
The epithelium (surface layer) heals in about three days. Vision may be somewhat blurry for the first several days but clears significantly by three to six days and 90% of the vision correction has taken place by this time. The remaining healing "fine tunes" the result slowly over the next several months. Appropriate follow-up care is important. Dr. Haight will outline the schedule of visits and medications to be used. These steps should be followed carefully as proper healing is critical to achieving the desired effect.

Unwanted effects of PRK can occur. Some individuals will be over or under corrected. This causes blurred distance vision, and may require spectacles, contacts or a retreatment. Rarely, patients develop haziness of the cornea severe enough to cause glare, halos around lights, or other night vision disturbances. Such cases may be treated with medication or additional laser. Some degree of glare may persist and is similar to that experienced with contact lenses. Some degree of dryness may also occur, requiring the use of artificial tears, or the placement of plugs in the tear ducts to retain natural moisture. Severe infections are also rare, but can occur. They are usually treated successfully with antibiotics.

To read PRK commonly asked questions, click here.

LASEK (laser in situ keratomileusis) is the newest evolution of the Excimer procedures. It combines the best elements of both PRK and LASIK. With this procedure the epithelium or skin of the outer cornea is loosened and gently lifted off the corneal surface as a sheet or "skin flap". Once the corneal surface is exposed, the laser treatment proceeds in the same manner as in PRK. The epithelium is then replaced back over the corneal surface returning to nearly the same position where it originated. Replacing the epithelium in this manner may permit a faster return of vision than with PRK and also decreases the foreign body sensation that accompanies PRK. The procedure, however, offers the safety of PRK in that no microkeratome is used and there is no mechanical cutting. Thus the potential complications of the thicker stromal flap used in LASIK are completely avoided. If the epithelial flap of LASEK is damaged it simply grows back in a few days. Results have shown similar outcomes to those of PRK and LASIK yet LASEK offers the bladeless, flapless, safety features of PRK with the faster initial visual recovery and improved comfort approaching that of LASIK. This procedure has not been reviewed by the FDA and is considered an off label use of the Excimer Laser.

A complete consultation will be needed to determine which of the forgoing procedures is best suited for each individual and a full explanation of the risks, benefits, and alternatives will be presented at that consultation.

Astigmatic Keratotomy (AK) is used to help people with astigmatism. Astigmatism is an uneven curvature of the cornea. It is curved more in one direction than the other, causing a distortion in vision. During AK, one or more surgical incisions are made in the cornea. These incisions help eliminate the uneven curvature and "round out" the cornea. A rounder cornea means objects no longer appear blurred or distorted. AK is sometimes performed at the time of cataract surgery, in order to reduce or eliminate the patient's preexisting astigmatism. It is also used to correct astigmatism following corneal transplants, radial keratotomy, or other forms of refractive surgery. It may be helpful in reducing some types of irregular or non-symmetrical astigmatism which current laser technology does not permit. AK may be performed as a preliminary procedure before laser vision correction.