American Academy of Ophthalmology answered:
LASIK is performed with the patient reclining under the laser in an outpatient surgical suite. First, the eye is numbed with a few drops of topical anesthetic. These drops may sting. An eyelid holder (called a speculum) is placed between the eyelids to keep them open and prevent you from blinking. A suction ring placed on the eye lifts and flattens the cornea and helps keep your eye from moving. You may feel pressure from the eyelid holder and suction ring, similar to a finger pressed firmly on your eyelid. From the time the suction ring is put on the eye, until it is removed, vision appears dim or goes black.
Your ophthalmologist may use an automated microsurgical instrument called a microkeratome to make a flap in your cornea. This device is attached to the suction ring. As the microkeratome blade moves across the cornea, you will hear a buzzing sound. The microkeratome stops at a preset point, far enough from the edge of the cornea to create a hinged flap of paper-thin corneal tissue. The microkeratome and the suction ring are removed from your eye, and the flap is lifted and folded back.
Some ophthalmologists use a specific laser instrument instead of a bladed microkeratome to make the flap in your cornea. With this technique, tiny, quick pulses of laser light are applied to your cornea. Each light pulse passes through the top layers of your cornea and forms a microscopic bubble at a specific depth and position within your cornea. Your Eye M.D. then creates a flap in the cornea by gently separating the tissue where these bubbles have formed. The corneal flap is then folded back.
As the flap is moved aside, your vision gets blurrier. Then a special laser for sculpting the cornea — preprogrammed with measurements customized to your eye — is centered above the eye. In most cases, a pupil tracker will be used to keep the laser centered on your pupil during surgery.
You will stare at a special pinpoint light called a fixation light or target light while the laser sculpts the exposed corneal tissue. The laser makes a clicking sound you can hear during the procedure. After the laser has completed reshaping the cornea, the surgeon places the flap back into position and smoothes the edges. The flap adheres on its own in two to three minutes.LASIK is performed with the patient reclining under the laser in an outpatient surgical suite. First, the eye is numbed with a few drops of topical anesthetic. These drops may sting. An eyelid holder (called a speculum) is placed between the eyelids... More