During the Procedure

After you have undergone a thorough examination and LASIK (or another type of refractive surgery) has been determined to be appropriate for you, the procedure is performed on an outpatient basis. The procedure takes about 15 minutes to perform for each eye. Both eyes are usually done during the same procedure, although there may be times when you or the surgeon prefers to have each eye done at different times.

• Prior to the procedure, most people will be given medication for relaxation. The eyes are anesthetized with eyedrops prior to the procedure. The eyes are cleansed, and drapes are applied to the eyelids to cover the eyelashes so they cannot interfere with the procedure. The eyelids are held open with an eyelid retractor.



• Once the preparations are complete and you are properly positioned under the laser, the surgeon will use an instrument called a microkeratome or a femtosecond laser to create the LASIK flap. Initially, a small mark is placed on the cornea to help realign the flap at the completion of the procedure. A suction ring is applied to the eye, which may cause a pressure sensation. The microkeratome or femtosecond laser creates a flap in the anterior cornea at about 20%-25% of its depth. The flap is then retracted back, exposing the corneal stroma or inner layer of the cornea.



• Next, the laser is used to resculpt the corneal surface. The laser portion of the surgery can take several seconds to several minutes to complete. During this time, you are asked to look (stare) at a target, such as a flashing red light or a flashing green light. The laser itself is invisible to you, although you will hear a loud tapping sound when the laser is firing.



• In myopic corrections, the laser works to flatten the central cornea. This allows light rays to focus onto the retina, reducing myopia.



• In hyperopic corrections, the laser is used in the peripheral cornea, causing a steepening of the central cornea, which allows better focusing of light rays onto the cornea.

• Once the laser portion of the procedure is completed, the flap is returned to its original position on the cornea. Through the natural characteristics of the cornea, the flap will seal itself in place after a few minutes. Usually, the flap is allowed to dry for approximately three minutes prior to removing the lid retractor. At the end of the procedure, antibiotic and antiinflammatory drops are put into the eyes.

• Usually, the full refractive error is corrected in both eyes, but some people desire a monovision correction. In this instance, one eye is corrected for distance, and the other eye is corrected for near vision. This type of correction may reduce the need for reading glasses.