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HOW LASER CORRECTION WORKS
 

A number of treatments have been developed to correct nearsightedness, farsightedness and astigmatism. Over the past several years, surgically changing the eye's focusing power is an option that has gained an increasing amount of public attention. Now, with the advent of the excimer laser, laser vision correction is gaining world-wide popularity.

 

Two laser vision correction procedures are available. Photorefractive keratectomy, or PRK for short, was developed first. However, an improved treatment called laser in-situ keratomileusis, or LASIK, is now becoming the most popular among patients and surgeons.

 
LASIK is a laser vision treatment that can correct high degrees of nearsightedness, farsightedness and astigmatism. This procedure utilizes a precise motorized instrument called a microkeratome to create a hinged flap of tissue on the center of the cornea. The flap is lifted back and the laser reshapes the underlying tissue. The flap is then replaced and adheres without the need of sutures.

 
Most of the world's experienced refractive surgeons have recognized LASIK's advantages and perform it as their procedure of choice.
 

History


In 1960, South American surgeon Jose Barraquer performed an operation in which he removed a thin section of the cornea, reshaped it like a contact lens, then replaced it. Encouraged by his experience, surgeons introduced the procedure to the United States in 1980. However, a number of factors kept this original procedure from becoming widespread.
 

Creation of a sophisticated instrument call a microkeratome made the removal of very thin layers of tissue easier and more successful. A treatment evolved called automated lamellar keratoplasty (ALK). With this procedure, surgeons used t he microkeratome to simply create a flap of tissue, instead of completely removing the thin layer from the cornea. With the flap lifted out of the way, a second pass of the instrument then removed a microscopic amount of underlying tissue to correct the focusing problem. When the treatment was completed, it was easier to align and reattach the hinged flap.
 

With the highly advanced excimer laser, surgeons have combined the microkeratome's ability to create a precision flap with the accuracy of the laser in removing underlying tissue. The combination of ALK and PRK is called LASIK. It is a treatment option that has overshadowed traditional PRK.

 

Range of correction


LASIK can treat nearsightedness and farsightedness (if the first number on your glasses prescription is between +5.00 and -20.00. Astigmatism up to -8.00 can also be treated).

 

Possible risks and side effects

 

Even though LASIK is a relatively safe procedure with a history of very few complications, these risks and temporary side effects should be considered:

 

Infection

Corneal Flap Problems

Undercorrection or Overcorrection

Corneal Surface Irregularities

Contact Lens Intolerance

Halo Effect Light Sensitivity

Fluctuating Vision

Eye Coordination