For thousands of years, humanity has been using eyeglasses to improve eyesight. More than two millennia ago, the ancient Romans discovered the ability to use glass to enhance their capacity to see fine print by creating small magnifying glasses with spheres. The first wearable eyeglasses appeared in Italy in the 13th century. Primitive blown-glass lenses were set into wooden, leather or animal horn frames and then held in front of the face. This was the genesis of eyeglasses.
Glasses and contact lenses
Eyeglasses are the most common way to overcome problems with eyesight, such as shortsightedness (hyperopia), which necessitates the use of lenses that enlarge the image. For those suffering from farsightedness (myopia) and need to focus the image, the eyeglasses contract the light rays and thereby focus the image.
However, eyeglasses are not so popular anymore. Wearing glasses is not perceived as attractive, and they tend to make people look older.
In an effort to improve the way we look (and see!), human ingenuity sought ways to improve on eyeglasses. The result was contact lenses. Contact lenses do not affect one’s appearance, as they are practically invisible.
But like all things, they have their advantages and disadvantages. The main advantage is esthetic. They improve one’s appearance. The disadvantages are many. Contact lenses may have a long-term negative effect on the eye, so it is recommended to avoid wearing them for long periods at a time. They also decrease the amount of oxygen that reaches the eye, which is critical in keeping the eye healthy. They also cause dry eyes because they reduce the amount of tears that reach the cornea. Contact lenses also diminish the corneal reflex and may cause corneal abrasion. If the contact lenses are not fitted properly or the eyes are too dry, the contact lenses may scratch the cornea, causing corneal abrasion. To further avoid the chances of corneal abrasion, it is strongly advised to remove the contact lenses before going to sleep.
All in all, contact lenses may enhance one’s appearance, but they are less healthy and less practical than eyeglasses. For example, putting them in and taking them out takes time.
Laser surgery
In many cases, laser technology can dispense with the need for eyeglasses or contact lenses. The technology is called LASIK (laser-assisted in situ keratomileusis), commonly referred to as laser eye surgery or laser vision correction. It is a type of refractive surgery for the correction of myopia, hyperopia and astigmatism. As mentioned, myopia is a medical situation that affects the ability to see distant objects with clarity. Hyperopia affects the ability to see objects within close range. In the first instance, contact lenses or eyeglasses contract and focus the image. In the second, they enlarge the image. Astigmatism is a type of refractive error in which the eye does not focus light evenly on the retina. This results in distorted or blurred vision at any distance. Other symptoms can include eyestrain, headaches and trouble driving at night. If astigmatism occurs early in life, it can result in amblyopia, the so-called lazy eye, whereby the coordination of the eye and brain is less than perfect.
People who suffer from myopia, hyperopia or astigmatism can be aided by laser surgery, thereby dispensing with the need for eyeglasses or contact lenses. LASIK is performed by an ophthalmologist, who uses a laser or microkeratome to reshape the cornea in order to improve visual acuity. For many people, laser surgery provides a long-lasting alternative to eyeglasses or contact lenses.
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