Contact Lenses Eyeglasses

The contact lens technology is the most popular replacement for eyeglasses. If you have an impaired vision, then going with modern contact lenses have become one of the most popular choices.

When do you have a vision problem? When your cornea - the natural lens inside your eye that has existed since you were born - changes its curvature or experiences a change in its refractive capability, the external light rays do not fall onto the right vision spot (”yellow spot” and its surroundings) inside your eyes. As a result, your vision becomes blurred. The job of your contact lens is to provide the additional refraction so that the focus of the external light entering your eyes is centered on your yellow spot, and you gain back your accuracy of vision. To understand what sort of contact lenses would work the best for you, you need to understand the above-mentioned process in more detail.

Historically speaking, the scientists of the past had observed the refractive properties of glass as well as of water, and had wondered whether such properties could leverage weakened human vision. A series of experiments led to the discovery of eyeglasses. This concept further evolved to place the glass right on the surface of the eye, and eventually this led to the birth of contact lenses. So fundamentally, both eyeglasses and contact lenses work based on the same principle - by providing compensation for the changes in the refractive index of your eyes.

The changes in your eyes can happen in two different ways. Either the shape and/or the refractive index of your eye changes such that the light entering your eyes focuses before the yellow spot, or the light focuses beyond the yellow spot. This leads to nearsightedness or farsightedness. For accurate vision, this light must focus exactly on your yellow spot.

The corrected refractive index provided by the contact lens will let you do exactly that. Once the lens fits your eyes, the light first has to travel through the lens and only then can it reach your eyes. The lens would change the direction of the light such that with your current refractive index of your eyes the focus happens exactly on the yellow spot of your eyes.

Now you understand the reason why your ophthalmologist would examine your eye to figure out exactly how much your eye has deviated from its expected vision levels. Based upon the desired refractive index found and also based upon your habits, lifestyle, and possibly profession, s/he will prescribe the appropriate type of contact lenses for you.

Contact lenses are evolving as technology evolves. So, knowing how the contact lenses fundamentally work and being aware of the different kinds of lenses available, you can make the right choice of your lenses.

Our eyesight is a precious gift, so no matter what your age, taking care of your vision is essential to good health. The brain is primarily responsible for managing the vision process. The brain processes the light information our eyes collect to create the images that allows us to see. In order to make sure our brain’s vision process maintains optimal performance, we need to nourish our eyes with healthy foods rich in vitamins and minerals.

All of the vitamins that are good for the eyes are Vitamins A, B, C, D, and E. Some of the most important vitamins needed to maintain optimal eye health include:

Vitamin C:  This vitamin has been associated with the prevention of cataracts, delaying macular degeneration, and reducing eye pressure in glaucoma patients. Our bodies are unable to store Vitamin C; therefore it needs to be replenished regularly.

Vitamin A: This vitamin is essential for eye and vision health. In our bodies, vitamin A is essential for the retina to help it function properly. One of the causes of night blindness is Vitamin A deficiency.

Lutein:  Lutein reduces the risk of cataracts and macular degeneration. Low Lutein levels have been shown to be a risk factor in age-related macular degeneration. Lutein may also help to prevent or slow the rate of atherosclerosis.

Vitamin E: This vitamin helps protect against cataracts and age-related macular degeneration.

Copper Gluconate: This is an absorbable form of the mineral copper. It is one of the most important blood antioxidants which help the blood carry oxygen and other nutrients to the rest of the body. The eyes are one area that requires oxygen. If there is a decrease in the transport of oxygen to the eyes, eventually vision loss can take place. Copper can be found in such foods as seafood, beans, nuts, organ meats, and whole grains.

When you choose foods for promoting and maintaining good eye health, you need to choose leafy and green fruits and vegetables. The brighter and deeper colored produce are full of the highest levels of vitamins and minerals.  They are packed full of antioxidants, which are essential for the eye lens, as well as for retinal, conjunctival, and corneal health. These vitamin and mineral rich foods nourish your eyes.

Among the foods that help you strengthen your eyes and see better are carrots, celery, parsley, spinach, bean sprouts, turnip greens, beetroots, cucumber, raw egg yolk and liver. Also recommended are tomatoes, beets and red peppers, apricots, raisins, sunflower seeds, pecan nuts, wheat germ, sweet potatoes, mangoes, cantaloupes, peaches, soy beans and lecithin. Blending the red foods with the dark green foods will give you all of the essential vitamins and nutrients required for good eye health. Dark green foods can include broccoli, kale, spinach, collard greens, and water cress. Avocado, asparagus, and yams are a great source of Vitamin E. Foods rich in Vitamin A includes sweet potatoes, carrots, mangoes, spinach, and cantaloupe.

It may seem difficult to change one’s diet. For the health of your eyes, you should adopt a health diet rich in vitamins and minerals. By including eye nourishing foods in your diet, you will not only find your self seeing better, but feeling over all good health.

Low Vision, also referred to as poor vision, is when a person loses their sight which is not completely restored using such aids as surgery and prescription eyeglasses. Such sight loss can include poor night vision, blind spots, and a glare preventing one from seeing clearly. Total blindness is not considered low vision because there is still some sight with low vision. Low vision is normally associated with people who are “legally blind” and require vision aids.

The American Optometric Association classifies low vision in two categories:

Partially Sighted: Visual acuity is between 20/70 and 20/200 with conventional prescription lenses.

Legally Blind: Visual acuity no better than 20/200 with conventional correction and/or a restricted field of vision less than 20 degrees wide.

The World Health Organization classifies visual impairment as:

-    20/30 to 20/60:  Mild vision loss, or near-normal vision
-    20/70 to 20/160: Moderate visual impairment, or moderate low vision
-    20/200 to 20/400: Severe visual impairment, or severe low vision
-    20/500 to 20/1,000: Profound visual impairment, or profound low vision
-    less than 20/1,000:  Near-total visual impairment, or near total blindness

Low vision can result from a number of conditions that can include inherited diseases, birth defects, macular degeneration, glaucoma, cataracts, and physical injuries. It can also result from such circumstances as diabetes, cancer of the eye, albinism, or a brain injury. Eye care specialists can diagnose low vision by using lighting, magnifiers, and visual testing charts. Low vision is often seen in adults over 45, especially the elderly.

The most common types of low vision include:

-    Central Vision Loss: A blind spot in the center of a person’s vision.
-    Peripheral Vision Loss:  Cannot see on either side, above or below eye level.
-    Night Blindness: Problems seeing in poorly lit areas.
-    Blurred Vision: Objects both near and far are blurry. For instance, refractive error is an eye disease where the shape of the eye does not bend light properly, resulting in a blurry image. Common refractive conditions include myopia (short sight) hypermetropia, (long sight) presbyopia, (aging of the lens) and astigmatism (irregular curvature of the lens.)
-    Hazy Vision:  Vision appears to be covered with a film or glare.

Sign that may suggest low vision include:

-    Not recognizing faces
-    Performing activities where you find yourself looking closely such as when reading, watching television, or sewing.
-    Picking out the wrong clothing colors.
-    Turning on bright lights to see well.
-    Unable to read street signs

Low vision can often be treated using such aids as hand magnifiers, lenses that filter light, reading prisms, magnifying glasses, telescopic glasses, and closed-circuit television.
Non medical aids that can help a person with low vision include talking watches and clocks, text reading software, large print books and magazines, clocks, phones, and watches that have larger numbers, etc.

Due to technological developments in the field of low vision rehabilitation, today most people suffering from low vision can be helped to improve the quality of their lives. Visual aids improve both sight and the quality of life for many people. If you are having problems with your sight, see an eye doctor for testing.