Your Guide to LASIK Eye Surgery
Your 5-Minute Guide to LASIK Eye Surgery
The principal elements of the eye’s focusing system are the cornea and lens. In order for one to see clearly, these structures must work together to create a sharp image on the retina.
Laser eye surgery creates clear distance vision by reshaping the cornea. Common focusing problems such as myopia (nearsightedness), hyperopia (farsightedness) and astigmatism are treatable. However, due to presbyopia, an aging process of the eye’s internal focusing system, patients over 40 still need reading glasses to see up close.
For patients who wish to reduce their need for reading glasses, a monovision correction is a viable alternative. With monovision, the dominant eye is corrected for distance and the non-dominant eye is left blurrier at distance, but better up close.
There has never been a better time to have laser eye surgery, as advancements in technology have made today's procedures safer and more effective than those available just a few years back. The major upgrades in technology include:
Flying spot lasers now allow individual laser pulses to target any location on the cornea, as opposed to older lasers, which can only vary the treatment diameter around a central reference point.
Trackers: These camera-based systems monitor the eye for movement during the laser treatment. If movement is detected, the laser’s targeting system makes a compensatory adjustment.
Wavefront guidance involves measuring the eye’s unique, fingerprint-like distortion pattern with a wavefront analyzer and then using the resultant wavefront map to create an individualized or “custom” treatment plan.
Prior to wavefront technology, all treatments were based on eyeglass prescription measurements obtained from the familiar “Which is better, one or two?” instrument. A number of published studies have shown that wavefront-guided treatments produce better visual acuity and superior night vision.
Automated registration is a means of assuring that each laser spot is delivered to the exact location on the cornea from which the wavefront data was obtained. It involves taking a picture of the eye during capture of the wavefront map and again just before the laser treatment. Static landmarks from each picture are then referenced to align the laser.
LASIK is the most familiar vision correction procedure, but it is by no means the only one commonly performed. In fact, many surgeons prefer alternatives such as IntraLASIK (all-laser LASIK), PRK, LASEK and epi-LASIK.
LASIK and IntraLASIK are flap procedures, which means that a thin flap of corneal tissue is lifted away from the underlying layers and the laser treatment is placed on the exposed surface. Afterwards, the flap is put back in place, where it covers the treated area.
LASIK and IntraLASIK differ solely on the instrument used to create the corneal flap. With LASIK, the flap is created with an instrument known as a microkeratome. With IntraLASIK, the flap is created by a laser manufactured by Intralase Inc.
PRK, LASEK and epi-LASIK are flapless procedures. They are distinguished by subtle variations in surgical technique. Flapless procedures are attractive because they eliminate any possibility of flap-related complications, but they have the downside of a longer, more uncomfortable recovery.
Not everyone qualifies for laser eye surgery. Military personnel, pilots and others with an occupational need for perfect vision should exercise caution, because it is impossible to guarantee a perfect outcome.
In addition, the FDA lists several medical conditions as contraindications to surgery. Contraindications are reasons why a person absolutely should not have surgery. They include:
Pregnancy and nursing
Immune deficiency: HIV, etc.
Collagen vascular diseases: rheumatoid arthritis, lupus, etc.
Keratoconus: a degenerative corneal disease
Certain medications: Accutane, amiodarone and triptan family migraine treatments
While contraindications are almost always a “black or white”, “yes or no” issue, warnings represent more of a gray zone and surgery is sometimes still possible. Common warnings include:
Herpes Keratitis: herpes infection of the cornea
Severe dry eye disease
Precautions are other issues that necessitate caution. Precautions include:
Age: Patients must be at least 18 to 21 years old, depending on the laser system.
Stability: Laser vision correction should be avoided if the eyeglass prescription is still changing.
Corneal disease, abnormality or prior surgery
Uveitis: inflammation of the inside of the eye
Blepharitis: inflammation of the eyelid margin
In addition to the issues that affect one’s candidacy for surgery, laser vision correction patients should be aware of the potential side effects.
More common side effects include:
Delayed epithelial healing: slow healing the eye’s surface (typically after a flapless procedure)
Diffuse lamellar keratitis: inflammation under a flap
Epithelial ingrowth: migration of the surface epithelium underneath the flap
Flap striae: wrinkles in the flap
Glare and halos around lights at night
Haze: superficial corneal opacification found almost exclusively with flapless procedures
Over or undercorrection necessitating a second treatment
Pain and light sensitivity: common within the first 3 to 5 days after a flapless procedure
Less common side effects include:
Loss of best-corrected vision: postoperative vision with glasses that is not as clear as the preoperative vision was with glasses
Decentration of the laser treatment
Ectasia: a region of the cornea that becomes progressively more distorted
Bad flaps: creation of an irregularly shaped flap that causes abortion of the procedure
When choosing a surgeon, reputation, board certification and experience are commonly cited prerequisites. But, even though a surgeon’s background is a useful starting point, there is no substitute for an in-person consultation.
At the consultation, look for a clean, well-organized office with a friendly, efficient, detail-oriented staff. The surgeon should be available, willing to talk openly about potential complications and able to provide his or her own outcome statistics.
When considering the cost of laser eye surgery, it is first necessary to clearly define what is included in the quote, as some centers offer all-inclusive pricing and others quote the preoperative exam, procedure, medications, postoperative care and retreatment coverage separately.
When comparing apples to apples, the price of laser vision correction does not vary as much as many people believe. This becomes clearer as one learns the factors that influence prices. Features that command a higher price include surgeon-provided care, detailed preoperative testing on top-shelf instruments, an Intralase flap and wavefront-guided custom laser treatment. An entire section of the Lasik MD website is dedicated to realistic prices.
As LASIK experienced a meteoric rise in popularity in the late 1990’s, a number of corporate entities entered the marketplace with advertisements for bargain-basement prices. Several credible sources have verified that the advertised prices are virtually impossible to obtain, which has led many consumer advocates to criticize the ads as little more than a classic bait-and-switch.
The real reason for “teaser price” ads is that they make the center’s phone ring. When patients call, they are told they must come in to the center for measurements to see if they qualify for the low price. Only after arriving at the center do most patients learn that the true price is much higher – typically as much or more than what other local providers charge. Despite the higher price, many patients capitulate to high-pressure sale tactics and have surgery with the center, rather than facing the disappointment of going back home and starting all-over.
In the decade since its introduction, laser vision correction has successfully cleared the vision of millions of people. In fact, LASIK is now the most commonly performed surgical procedure in the world. The next step in your quest for visual freedom is to learn more from a local provider.Please visit our worldwide surgeon directory to find a surgeon or center near you.