LASIK surgery is a type of refractive laser eye surgery performed by ophthalmologists to correct myopia, hyperopia, and astigmatism. It is a surgical alternative for wearing corrective contact lens or eyeglasses.
A patient, who will undergo LASIK surgery, will be required to have their corneas be examined with a pachymeter to determine its thickness, and with a topographer to measure the surface contour. A low-power laser, a topographer, is used to create a topographic map of the cornea. With the information obtained, a surgeon will calculate the amount and locations of corneal tissue to be removed during the operation. The patient typically is also prescribed an antibiotic to start taking beforehand, to minimize the risk of infection after the procedure. Also, patients wearing soft contact lenses are usually instructed to stop wearing them approximately 5 to 7 days before surgery.
The patient is awake and mobile during the LASIK surgery operation; however, a mild sedative (such as Valium) and anesthetic eye drop is sometimes given to the patient.
Performing LASIK surgery involves three main steps. Creating a flap of corneal tissue is the first step. The second step involves the remodeling of the cornea underneath the flap with the laser. The last part is where the flap is then repositioned.
Flap creation
This step involves a corneal suction ring to be applied to the eye so as to hold the eye in place. This step in the procedure may have a harmless side effect wherein small blood vessels burst that result to bleeding or subconjunctival hemorrhage into the white area (sclera) of the eye which resolves within several weeks. An increased suction causes a transient dimming of vision in the treated eye. Once the eye has been immobilized, the flap is then created. This process is achieved with the use of a mechanical microkeratome using a metal blade, or a femtosecond laser microkeratome (procedure known as IntraLASIK) that creates a series of tiny closely arranged bubbles within the cornea. At one end of this flap a hinge is left. The flap is then folded back, revealing the stroma, the middle section of the cornea. This process of lifting and folding back the flap can be a bit uncomfortable.
Laser remodeling
The second step of the procedure uses an excimer laser (193 nm) to remodel the corneal stroma. The laser vaporizes tissue in a very controlled manner avoiding damage to the adjacent stroma. Tens of micrometers thick layers of tissue are then removed. During this second step, the patient’s vision will become very blurry once the flap is lifted. Only white light surrounding the orange light of the laser can be seen which can be disorienting sometimes.
Reposition of flap
After the stromal layer has been reshaped by the layer the LASIK flap is carefully repositioned over the treatment area by the surgeon. The presence of any air bubbles or debris, and proper fit on the eye is also checked. The flap will remain in position by natural adhesion until healing is completed.
Patients are usually given a course of antibiotic and anti-inflammatory eye drops after the surgery which is continued in the weeks to follow. They are also advised to sleep much more and are also given a darkened pair of shields to protect their eyes from bright lights and protective goggles to prevent rubbing of the eyes when asleep and to reduce dry eyes. Moisturizing the eyes with preservative free tears and follow directions for prescription drops is also important. Patients should be properly informed by their surgeons of the importance of proper post-operative care.
E-mail: 
