Jun

17

What You Need To Know About Vision Problems and Solutions

Filed Under Eyewear Knowledge 


How the eye works. If you’re like me, then you’ll need a quick overview on the layout of the eye in order to understand problems related to vision.

Light is refracted to the eye through the cornea (the thin layer over the whole eye) and then through the pupil (the black part) which is controlled by the iris (the colored part) and then refracted again by the lens. Together the cornea and lens take the combinations of light and send them, inverted, to your retina. At this point, you have an upside-down series of lights displaying an upside-down down image on the back of your retina, like a movie projector turned on its axis displaying light to the film screen.

            Your retina contains rods and cones. Rods are for peripheral vision while cones support the perception of color variations. Through various bipolar and ganglion cells information is transmitted through the optic nerve to the brain, where it is processed by the visual cortex. To stick with the movie analogy, rods make the edges of the film appear as sharp as the middle while cones allow your film to be color-saturated.

Why problems occur. Sometimes problems occur in the eye. Often people are born with minor defects, or they can develop defects through bad habits or bad luck. For example, when little Johnny stared at the sun for hours on end as a child, he later developed blurring in his eyes and a decrease in long-distance vision. Silly Johnny should wear sunglasses with UV protection if he plans to stare at bright lights, and even then little Johnny isn’t being smart. Nearsightedness can be developed when a person stares too often at objects that are very close. A computer screen, for example (tsk, tsk!). Farsightedness can develop with age, though some are born with or develop this defect for unknown reasons.

Common eye-related problems. Near sightedness is called myopia by optometrists, and is characterized by the patient’s ability to focus on close objects while background objects tend to blur. The condition occurs in the eye when the image you are looking at gets crossed as it is transmitted through the retina, thus there is an overlap when the inverted image is displayed. This is oversimplified, and any optometrist would faint at this simplistic explanation. Myopia is treated by giving an eye exam that measures the extent of the overlap in background images. This exam is measured in diopters, which is the strength or weakness of the corrective lens. Low myopia is measured at a -3.00 range, for example, and measure for concave lenses.

Far sightedness is called hyperopia by optometrists and is characterized by the patient’s ability to focus on far away object while nearby objects remain blurry. It is the opposite of myopia. This defect occurs when images are refracted to the retina too deeply, i.e- the image is whole beyond the retina, and thus near objects are blurred while far ones reach the retina at accurate lengths. This occurs naturally with age, which is why older folks more often have reading glasses than their younger peers. This is corrected with lenses measured in a positive diopter scale, so an average low measure would be +1.40, for example, and measures for convex lenses.

Eye-exercises. In addition to wearing corrective lenses and sunglasses to protect you from dangerous UV rays, you can supplement your eye-care with the addition of the Bates method. The Bates method is a series of eye exercises that attempts to counter the damage done to eyes from poor habits (like Little Johnny’s mistakes, or yours, reader, as you stare at the computer screen). Though some optometrists claim that the Bates method is only a theory, others are adamant practitioners. Bates believed that psychological strain cased refractive and accommodation errors in the eye, and could be reversed by exercising the eye.

            Thus, the best way to care for your eyes is as follows. Get an eye exam to determine if you need glasses. Purchase high-quality glasses– don’t skimp when it comes to your health! If you know you need glasses, the longer you squint and strain the worse you are making the refractive error. When not indoors, wear sunglasses to protect you from UV rays. Proscription sunglasses are available. Finally, try out the Bates method eye-exercises and see for yourself if they help. Finally, don’t stare at the sun, or at close objects at length. Simply glancing away from the computer screen every few moments will exercise and condition your eyes.

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