It is an outpatient treatment first performed in 1987 that uses a light beam to gently reshape the surface of the eye (the cornea) and improve vision. The light gently pulses to remove microscopic amounts of tissue, altering the curvature of the cornea and allowing visual images to be more sharply focused on the retina.
Laser vision correction reduces or eliminates nearsightedness, farsightedness, or astigmatism and, with it, reduces the need for glasses or contacts.
The normal eye is a perfect sphere, where the cornea and lens focus light to form an image on the back inside surface of the eye, known as the retina. With nearsightedness (myopia), the cornea's curvature is too steep for the shape of the eye. The light is focused in front of the retina, causing images of distant objects to appear blurry.
In a farsighted (hyperopia) eye, the image focuses beyond the retina. In our youth, the innate accommodating (focusing) power of the eyes often compensates for farsightedness. But as we age, our eyes become less able to accommodate. For this reason, farsightedness most commonly becomes a problem later in life. Many people with farsighted eyes do not need correction until they reach their 40s or 50s.
The front of the astigmatic eye has an irregular shape – more oval – like a football. Incoming light focuses at multiple points instead of one.
Astigmatism can make wearing contact lenses difficult or even impossible. Laser vision correction with an excimer laser is now an FDA-approved option for people with astigmatism.
The cool beam of light gently reshapes the surface of the cornea, making it more like a normal eye. Light can then focus at the back of the eye, on the retina, improving vision by making images on the retina clear.
Both LASIK and PRK utilize an excimer laser to reshape the cornea. The laser is so precise that it takes several pulses of light to remove a single cell.
In PRK, the laser is used on the surface of the eye, which requires a slightly longer healing time. Discomfort with PRK is typically mild, but it is more noticeable than with LASIK.
LASIK involves creating a thin flap of tissue, retracting the flap, and applying the laser underneath the flap. The flap is then replaced, and it adheres very quickly on its own. LASIK patients typically describe the procedure as completely painless.
Both LASIK and PRK produce excellent results for most patients. However, LASIK is by far the most commonly performed refractive procedure worldwide. LASIK offers the advantages of very rapid recovery of vision, minimal or no discomfort, and excellent accuracy.
There are some patients who are better candidates for PRK however. Generally speaking, these are patients with very thin corneas, or corneas with certain types of surface abnormalities. Additionally, a few patients with very large pupils may also be better candidates for PRK, but this is determined on an individual basis.
A complete eye exam with one of our doctors can identify the best option for you.
Yes. The FDA has approved the excimer laser for the treatment of nearsightedness, farsightedness, and astigmatism for eligible patients. Millions of patients worldwide have undergone successful laser vision correction procedures, and over one million excimer laser procedures have been performed in the U.S. since FDA approval in 1996.
Virtually all people treated experience an improvement in vision that would allow them to pass a drivers' license exam without the aid of glasses or contacts.
You will feel pressure sensations during the procedure. Your eye is numbed with eye drops that are instilled prior to the procedure and no general anesthetic is necessary.
Some patients have described having a slightly "sandy" feeling in their eyes immediately after the procedure; however, this feeling will go away as soon as eye drops are administered.
No. You can have laser vision correction as soon as you're ready for it.
As people approach their mid-40s, it is natural for them to begin losing their ability to focus on both near and distant objects. This age-related change is called presbyopia. It is the result of the lens in the eye becoming less elastic and losing its ability to change its focus.
Reading glasses or bifocal lenses usually relieve age-related focusing problems. People with low amounts of nearsightedness can simply remove their glasses to read. Contact lens wearers can use reading glasses over their contacts.
Another contact lens option is to wear one lens corrected for near vision in one eye and another corrected for distance vision in the other eye. This is known as monovision.
Monovision may also be an option for those considering refractive surgery. The advantage of monovision is being able to both read and see in the distance without corrective lenses. This option might be particularly helpful for people who frequently shift their vision between near and far distances.
Laser vision correction at the St. Paul Eye Clinic can now be tailored to the unique characteristics of your eyes with VISX CustomVue™ LASIK.
At the heart of the CustomVue procedure is the WaveScan® system. This system allows our experienced LASIK surgeons to measure and correct visual imperfections that were previously undetectable with the common technology used to prescribe glasses and contact lenses.
By specifically addressing the unique imperfections of your vision, we can help you safely and effectively achieve your “personal best vision” without glasses and contact lenses.
Learn more about CustomVue LASIK.
Our physicians will conduct a thorough examination to determine whether your eyes are healthy and suitable for the procedure. Then your eyes will be photographed and a computerized map (corneal topography) will be created. This "map" will assess the shape of your cornea and is one of the many diagnostic tests we use to help plan your procedure.
Laser vision correction is an outpatient procedure that takes minutes to complete for most patients. Your entire visit will be complete in about 2 hours. During the procedure:
- Anesthetic drops will be placed in your eye and you will be positioned under the laser.
- A retainer will be used to gently and comfortably hold your eyelids open during the procedure.
- You will be asked to focus on a blinking light for a minute or less.
- The doctor will view your eye directly through a surgical microscope to ensure that you are fixating properly and can pause at any time.
Once finished, you will get up, receive instructions from the staff, and rest for a few minutes. Afterward, you'll go home to rest and relax for several hours.
Results vary with each individual. Most patients having the procedure report that they could pass a state driver's exam without glasses or contact lenses.
Vision usually improves within 12-24 hours after treatment, though it's normal that some patients may experience small visual changes during the first several months.
Your physician will consult with you prior to undergoing the procedure to discuss the benefits and risks of LASIK.
Most people return the day after treatment.
The physicians of St. Paul Eye Clinic will advise you if laser vision correction is right for you. Some basic guidelines are:
- You must have healthy eyes.
- Your vision must be stable for at least one to two years before the laser procedure.
- You are not a good candidate if you have degenerative or autoimmune diseases, if you're pregnant or nursing, or if you have a condition that deters or slows healing.
There are risks that accompany all surgical procedures; however, the risks for laser vision correction are generally low.
Laser vision correction is performed using a computer-controlled light beam under the guidance of a trained and certified eye doctor. We will be pleased to discuss with you the risks and benefits of laser vision correction.