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The following information has been supplied to help you better understand a few of the terms and definitions used in the eye care field. It is our hope that the information supplied will assist you in recognizing problems or potential problems from the convenience of your home computer.
Tonometry: measures fluid pressure within the eye.
Computer-assisted visual field testing: checks for vision loss.
Stereo optic nerve head photography: verifies the condition of the optic nerve.
(Some services may be preformed by other professionals that we recommend.)
Laser trabeculoplasty: stretching open the drainage channels in the eye to relieve pressure.
Laser iridotomy: tiny hole made in the iris to relieve pressure .
Trabeculectomy filtering surgery: surgical opening within the eye to relieve pressure.
Implant surgery of tubes, valves and shunts: inserted into permanent openings in the eye to relieve pressure.
Cyclodestructive treatments: procedures to slow the fluid production of the eye.
Nearsightedness, or myopia (Greek word, meaning to squint), is one of the most common refractive problems. It affects 25% of the North American population and usually results from an eyeball that has developed longer in size than normal. In some cases, a steeply shaped cornea can also be the cause. Light passing through an elongated eye focuses before it hits the retina. People who are nearsighted can see near objects more clearly than distant ones.
Farsightedness, or hyperopia, is usually caused by an eyeball that has developed shorter in size that normal. In some cases, a flatly shaped cornea can also be the cause. Light passing through a short eye reaches the retinal before it is brought into focus. People who are farsighted are able to see distant objects more clearly, however, all objects may be blurred.
Astigmatism is a general inability of the eye to focus clearly at any distance because of irregular corneal curvature. Instead of being uniformly rounded, the cornea is steeper in some areas and flatter in others. In other words, it is shaped more like a football than a basketball. A misshaped cornea causes light rays to focus at several points on the retina causing distorted vision. Astigmatism is often combined with nearsightedness and farsightedness.
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:

A cataract is a cloudiness that develops in the normally clear lens of the eye. The lens, about the size of an aspirin, is the transparent fine focusing part of the eye located behind the pupil. It is comprised of a strong, transparent outer covering or capsule filled with a clear gel material. When the gel becomes cloudy, the incoming light rays are distorted or blocked before reaching the retina at the back of the eye. As the cataract develops, vision is increasingly reduced. Your family optometrist will usually discover developing cataracts in the course of routine eye exams. If you have cataracts that are causing visual difficulties, your doctor will usually recommend surgery, the only known cure for cataracts.
Causes of cataract development Cataracts are most commonly caused by age. In fact, almost everyone who lives long enough will develop cataracts. Age-related cataracts are brought about by chemical changes within the lens of the eye. These changes result in the lens hardening and becoming cloudy.
Cataracts can also be caused by severe injuries to the eye, reactions to certain drugs, exposure to harmful chemicals or radiation, and some eye diseases and physical conditions such as diabetes. Smoking and exposure to high amounts of sunlight have been shown to increase the onset of cataract formation. Babies can also be born with congenital cataracts.
Cataract symptoms Cataracts vary in the way they develop, but generally, people experience one or more of these common symptoms:
Cataract solution Unfortunately, there is no way to prevent or reverse the development of cataracts. Although there is evidence that anti-oxidants such as vitamin A, C and E may delay their development, there is no known way to prevent cataracts or to make the cloudy lens clear again. If there are no other serious problems with the eye, an experienced cataract surgeon can restore vision in over 99% of the cases. In fact, cataract surgery is one of the most successful surgeries being performed. The surgery involves two main parts: First, the cloudy lens must be removed and secondly, the focusing power must be replaced.
Removing the cloudy lens Instead of removing the entire lens and capsule, the most modern treatment involves the surgeon making a small opening in the front of the clear covering to remove the cloudy gel inside the capsule. The rest of the capsule is left intact to provide a sac for holding the new artificial lens. The most ideal method of removing the gel from the lens is to use an ultrasound probe which vibrates at 40,000 times per second. This procedure, known as phacoemulsification, causes the least amount of trauma to the eye when performed by an experienced surgeon. Reaching into the capsule with the ultrasonic probe, the surgeon uses the controlled vibrations of the tip to break up the hardened, cloudy gel and suction it out of the eye.
Replacing the focusing power In removing the lens of the eye, the natural focusing ability is also removed during cataract surgery. To replace it, a tiny artificial lens implant, usually made of Plexiglas, can be inserted into the original lens capsule. This lens implant is held securely in place by gentle, flexible loops. Artificial lens implants are available in all ranges of power so patients can often achieve better vision than they have ever experienced. Although clear vision can be restored almost immediately, glasses still may be needed for some activities such as driving or reading.
Cataract surgery risk As with any surgery, there are risks involved with cataract surgery, though serious problems are very rare. Problems that do occur can generally be resolved so vision is not permanently lost. Under the care of an experienced surgeon, there is usually nothing to worry about. After-surgery care when a skilled surgeon performs surgery, patients normally return to their family optometrist for the after-surgery care. During this follow-up period, the surgeon and optometrist work closely to monitor vision and the healing process. The commitment of these two eye doctors working together provides the patient with the best care.
After-surgery clouding In about a third of cataract surgery cases, the clear capsule that holds the new plastic lens becomes cloudy or frosted over. Again, vision is reduced. Some people think their cataract has returned, but it can be easily treated with the laser. In a short office visit, the beam of laser light is used to make a small opening in the back of the cloudy capsule to restore clear vision.
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