If you have a refractive error, such as nearsightedness (myopia), farsightedness (hyperopia), astigmatism or presbyopia, refractive surgery is a method for correcting or improving your vision.
Refractive surgery might be a good option for you if you:
If you are considering refractive surgery, you and your Eye M.D. can discuss your lifestyle and vision needs to determine the most appropriate procedure for you.
LASIK (laser-assisted in situ keratomileusis) is an outpatient refractive surgery procedure used to treat nearsightedness, farsightedness and astigmatism. A laser is used to reshape the cornea — the clear, round dome at the front of the eye — to improve the way the eye focuses light rays onto the retina at the back of the eye.
For people who are nearsighted, LASIK is used to flatten a cornea that is too steep. Farsighted people will have LASIK to achieve a steeper cornea. LASIK can also correct astigmatism by shaping an irregular cornea into a more normal shape.
LASIK is performed while the patient reclines under a surgical device called an excimer laser in an outpatient surgical suite.
First, the eye is numbed with a few drops of topical anesthetic. An eyelid holder is placed between the eyelids to keep them open and prevent the patient from blinking. A suction ring placed on the eye lifts and flattens the cornea and helps keep the eye from moving. The patient may feel pressure from the eyelid holder and suction ring, similar to a finger pressed firmly on the eyelid.
From the time the suction ring is put on the eye until it is removed, vision appears dim or goes black. Once the cornea is flattened, a hinged flap of corneal tissue is created using an automated microsurgical device, either a laser or blade. This corneal flap is lifted and folded back. Then the excimer laser preprogrammed with the patient's unique eye measurements is centered above the eye.
The surgeon checks that the laser is positioned correctly. The patient looks at a special pinpoint light, called a fixation or target light, while the excimer laser sculpts the corneal tissue. Then the surgeon places the flap back into position, and stitches are not needed.
The patient should plan to have someone drive him or her home after the procedure and then take a nap or just relax. To help protect the cornea as it heals, the surgeon may place a transparent shield over the eye(s) to protect against accidental bumps and to remind the patient not to rub the eye(s). The surgeon will provide eyedrops to help the eye heal and relieve dryness.
It may take three to six months after LASIK surgery for the improvements in a person's vision to fully stabilize and any side effects to go away.
LASIK, like any surgery, has potential risks and complications that should be carefully considered. There is a chance, though small, that vision will not be as good after the surgery as before, even with glasses or contacts.
Some people experience side effects after LASIK that usually disappear over time. These side effects may include hazy or blurry vision; difficulty with night vision and/or driving at night; scratchiness, dryness and other symptoms of the condition called "dry eye"; glare, halos or starbursts around lights; light sensitivity; discomfort or pain; or small pink or red patches on the white of the eye.
Sometimes a second surgery, called a retreatment or enhancement, may be needed to achieve the desired vision correction. This is more likely for people who were more nearsighted, farsighted, or had higher astigmatism before LASIK
You should be comfortable with the possibility that you may need a second surgery (called a retreatment or enhancement) or that you might need to wear glasses for certain activities, such as reading or driving at night. Also, you should be aware that LASIK cannot correct presbyopia,
A microsurgical instrument called a trephine is used to create a flap of epithelial corneal tissue, and an alcohol solution is used to loosen the epithelial cells. Once the epithelial flap is created and moved aside, the procedure is the same as PRK. After corneal sculpting, the epithelial flap is repositioned and smoothed with a small spatula, then secured with a "bandage" soft contact lens to promote epithelial healing, which takes about four days.
Phakic IOLs are designed for people with high degrees of refractive errors that cannot be safely corrected with corneal-based refractive surgery. The phakic IOL, is surgically implanted inside the eye in front of the eye's natural lens. The eye's natural lens is not removed, so patients can retain their pre-existing ability to focus.
With PRK, your ophthalmologist uses a laser to change the shape of your cornea.
If you have dry eyes or thin corneas and want to have refractive surgery, PRK may be a good choice for you. This is because some other types of refractive surgery, such as LASIK, are not recommended if you have these conditions.
This is because PRK does not involve cutting a flap in your cornea .
PRK is usually done in an outpatient surgery center. The procedure usually takes about 15 minutes. Here is what to expect:
Your eye will be numbed with eye drops.Your eye surgeon will place an eyelid holder on your eye Then your ophthalmologist will remove the outer layer of cells on your cornea, called the epithelium. To do this, he or she may use a special brush, blade, laser or alcohol solution.You will be asked to stare at a target light so that your eyes will not move. The ophthalmologist then reshapes your cornea using a laserWhile your ophthalmologist is using the laser, you will hear a clicking sound.
Like any surgery, PRK carries risks of problems or complications you should consider. These include:
Also, with PRK, your vision may end up being undercorrected or overcorrected. These problems often can be improved with glasses, contact lenses, or additional laser surgery.
Most complications can be treated without any loss of vision. However, very rare problems may include:
If you are happy wearing contacts or glasses, you may not want to have refractive surgery. Together, you and your ophthalmologist can weigh the risks and rewards and choose the vest refractive surgery for you.