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Patient Education Company
Your doctor has recommended that you undergo Photorefractive Keratectomy - or PRK Laser surgery - to correct a vision problem. But what does that actually mean?
The human eye is constructed like a camera ... with a clear lens in the front and light-sensitive tissue at the rear. This tissue makes up the retina which acts like photographic film.
In an eye that has perfect vision, light rays passing through the pupil are focused by the lens to fall precisely at the center of the retina. There are many common problems that can affect the eye and prevent light rays from focusing properly on the retina.
Three of these problems, myopia - or nearsightedness; hyperopia - or farsightedness; and astigmatism can often be corrected or reduced with the use of PRK laser surgery.
Myopia, or nearsightedness, occurs when the shape of the eye is too long or the curve of the cornea is too extreme. In this case, light rays are focused on a point in front of the retina - instead of on the retina itself.
Hyperopia, or farsightedness, occurs when the shape of the eye is too short. In this case, light rays are focused on a point behind the retina.
Astigmatism occurs when the cornea is unevenly curved,
causing light rays to fall off center or not to focus properly at all.
In either case, PRK laser surgery can be used to flatten all or part of the cornea ... allowing your doctor to cause the focal point of light entering the eye to fall more closely to the center of the surface of the retina.
PRK is a simple and nonintrusive procedure that is designed to reduce or eliminate the need for glasses or contact lenses. PRK laser surgery generally does not have any effect on a patient's overall health and there are no risks in choosing not to have the surgery.
Your Procedure:
On the day of your operation, you will be asked to put on a surgical gown.
You may receive a sedative by mouth and an intravenous line may be put in.
You will then be transferred to the operating table.
and you'll be given an anesthetic in the form of eye drops and an eyelid holder will be placed around the eye to prevent blinking.
When the operative field is numb, the doctor will carefully remove the epithelium, or top layer of cells, exposing the stroma - the non-cellular portion of the cornea.
Next, your doctor will use a computer to control pulses of cool laser light.
These pulses will delicately remove microscopically thin layers of cells from the stroma. By removing tissue in this manner, your doctor will tailor the new shape of your cornea according to the exact nature of your vision problem.
The entire procedure usually takes about 5 minutes and is painless.
Following surgery, you'll be given protective contact lenses to wear for a few days while the outer layer of cells grows back.
Patient Education Company