Posts Tagged ‘macular’

Blindness – Low Vision At Work

What happens after you’ve hired that qualified person who is blind or low vision? Very often co-workers and supervisors have questions that center around wondering, “How do I work with him? How can I talk with her? What do I need to do differently?”

Blindness means that an individual has 10% or less of normal vision (80% of those who are legally blind have some degree of vision while 20% have none.) Low vision is a visual impairment, not correctable by standard glasses, contact lenses, medicine, or surgery, that interferes with the ability to perform everyday activities. Most people develop low vision because of eye disease such as cataracts, glaucoma, diabetic retinopathy or macular degeneration. Low Vision primarily affects people over the age of 65. macular degeneration products are widely available due to increasing aging population. Yes, for some workers who are legally blind, some tasks will be done using sight. This can get confusing if co-workers or supervisors believe only “total blindness” fits the definition of “blind” and it can lead to misunderstandings.

For example, a saleswoman in a department store in New Jersey is doing all necessary tasks well using her sight along with some low vision aids, with one exception. She physically cannot read numbers on products for inventory purposes. Her immediate supervisor thought she was malingering and “gave her a hard time” until he understood the parameters on her vision loss. He appreciated her understanding that he just needed the facts. Now during inventory, when the work is divided among the associates, she is given a necessary task that fits her strengths. The low vision aids, although not a complete solution, makes the saleswoman competitive.

Among those blind persons who have some sight, a few will read print, but will not have the ability to see people coming toward them on the other side of a hallway (“tunnel vision” or loss of field); some have “night blindness” but function with sighted techniques when there is enough light without glare; some will see general shapes and colors, or that lights are on. Some are totally blind and use blind techniques all of the time. There are other variations.

What matters is not how much sight is left but the amount of skill the blind person has in using blind techniques when sighted techniques won’t produce work on time, to the competitive level. A practical definition of blindness could be stated like this:

You are blind if you find it more efficient, some or all of the time, to use blind techniques rather than sighted techniques to perform tasks to a competitive level.

There are two suggestions that are likely to fit every case. First, it often helps blind colleagues if you verbalize. (For instance, don’t just point, say, “It’s on the left.”) Second, start with the assumption that the other adult is as competent as you are.

How to get more information on low vision products – Ask your Eye MD for a Low vision or Blindness Specialist. Low vision specialists are licensed doctors of optometry who are trained in the examination and management of patients with visual impairments. A few of them are ophthalmologists with additional training in low vision care. Their services do not offer a cure for the causes of low vision, but they do help the patient learn how to utilize their remaining vision to its fullest potential. Low vision care does not replace the possible need for other treatments such as laser, medication, and surgery.

Low Vision Specialist – Low Vision Technology

Article Source:http://www.articlesbase.com/vision-articles/blindness-low-vision-at-work-1125013.html

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Understanding Low Vision

For a sighted person, the loss of vision represents much more than a physical impairment. Macular Degeneration and other low vision conditions have contributed to a growing population of people relearning how to live. It means a loss of their accustomed independence: the end of driving to work, reading the local newspaper, even simple pleasures like playing catch. Macular degeneration products and other low vision magnifiers have gave way to life, but not enough. Through a new center based at Wayne State University, a multidisciplinary team of San Diego-area researchers and clinicians has begun work they hope will return a level of autonomy to the growing number of men and women who are facing the limitations of life without sight.

To put it plainly, “Low vision is not no vision.” The definition of blindness is a visual acuity of 20/200 in the best eye with best correction or a visual field of 20 degrees or less. While this definition sounds precise, it is often subjective. An eye specialist who uses an eye chart that does not measure acuities between 20/100 and 20/200 may give “the benefit of the doubt” and declare the patient “legally blind” in order to give the person access to more services. Thus, a person who reads regular print with no aids risks being placed in the same category with people who have a far lesser degree of visual functioning. Why, in an environment where time is measured in milliseconds and gasoline sales are measured in thousandths of a gallon, do we still consider “counts fingers” a viable visual measurement? Why do we continue to cling to an out-of-date standard? Unfortunately, mistakes and misunderstandings still occur. The definition of “legal blindness” is not even the same in all countries. It is simply a random designation arrived at by people with 20/20 vision to determine eligibility for gov. services.

A fact in the field of visual impairment is that a fully sighted person gets 80 percent of his or her information about the world visually. In the case of a low vision person, he or she is still receiving a vast majority of their sensory input by visual means. The point at which 80% becomes 50% or 5% is not something that is easily determined. Attempts to state a “percentage” of vision loss frequently fail to take into account factors other than visual acuity. In my opinion, if an individual demonstrates good visual functioning, this individual’s vision should be given the “benefit of the doubt” when considering educational and rehabilitation programming. Certainly it does not deserve to be ignored as if it were of no importance.

Low vision products help. The most common video magnifier for reading is called a Desktop Video Magnifier. These low vision aids feature a camera mounted over a tray on which the material to be magnified is placed. Some have a built-in monitor and are known as “stand-alone” magnifiers. Others are designed to connect to a television or personal computer.

How to get more information – Ask your Eye MD for a Low vision Specialist. Low vision specialists are licensed doctors of optometry who are trained in the examination and management of patients with visual impairments. A few of them are ophthalmologists with additional training in low vision care. Their services do not offer a cure for the causes of low vision, but they do help the patient learn how to utilize their remaining vision to its fullest potential. Low vision care does not replace the possible need for other treatments such as laser, medication, and surgery.

Low Vision Specialists – http://www.visiontechnology.com

Article Source:http://www.articlesbase.com/vision-articles/understanding-low-vision-1127804.html

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Eyesight Problems

            Eyesight is precious to everyone that has it. For most people, it would be the last sense that they would want to give up. Yet, the eyes and the various damages done to them are little understood by most people. The eyes are a complicated pair of organs in the body. Light reaches the eyes and is focused by the lens, which stretches or flattens in order to focus the light on the back of the eyeball, which is called the retina. The retina then turns the light energy into electrical energy, so that it can then be transmitted to the brain through the optic nerve. The brain then quickly processes the electrical signal information and forms a visual image of what originally entered the eyes. When any part of this process is disturbed, eye problems can result.

            Many of the most common eye abnormalities are genetically-based, such as nearsightedness and farsightedness. There is some vision retraining techniques to try and help these conditions; they are outside the scope of this article. Vision correction with lenses, or laser surgery, are the main treatments for both nearsightedness and farsightedness. There are also a number of relatively minor eye problems that can temporarily occur, including: allergies that affect the eyes, inflammation of the eyelid(s), eye pain, sties and lumps on the eyelid(s), bacterial or viral infection of the eye, chemical irritation, broken blood vessels in the eye (hemorrhage), dry eyes, and floaters. If you have an eye infection or suddenly notice significant changes in your vision, like blurriness that does not go away, or many gray floating specks in one or both eyes, notify your physician immediately.

             There is some controversy about whether eyes need ultraviolet (UV) light or not. UV light is invisible to us; it comes from sunlight and certain other light sources. UV light can damage both skin and eyes. However, UV light can also have positive functions on the body, such as activating vitamin D in the body. Also some practitioners believe that only full-spectrum light (full range light, including UV light) can keep certain organs and/or glands functioning properly. For example, the pineal gland needs adequate amounts of sunlight in order to function correctly. There is some evidence that the amount, quality, and spectrum of light help regulate basic behavioral functions, such as sleeping.

            An old saying is that the eyes are the windows to the soul, and in medical terms, that saying could include disease states as well. Conversely, certain diseases in other parts of the body can also affect eyesight. For example, one of the problems associated with diabetes is damage to the retina, which receives light at the back of the eye. This is usually diagnosed as diabetic retinopathy, and it is the leading cause of blindness in adult Americans (1). Controlling blood sugar through proper diet, exercise, and supplementation is the key to preventing or managing diabetic retinopathy. 

            Besides diabetes-induced eye problems, there are three main serious eye problems: macular degeneration, cataracts, and glaucoma. Macular degeneration is a serious eye disease that usually occurs in older people. It may have more of a genetic component than many other eye diseases. In this disease, the central part of one’s vision becomes increasingly blurry, and sometimes they cannot see objects in the center of their vision at all. Age-related macular degeneration affects 6% of Americans 65 and older; it affects 20% that are 75 and older (2).

            A cataract is a clouding of the eye’s lens. It is thought to occur by excess sunlight exposure. By age 64, there is at least a 50% chance that someone has developed a cataract. It’s not surprising then, that cataract surgery is the most common therapeutic procedure for Americans 65 and over (2). Symptoms include blurred vision, poor night vision/glare, nearsightedness, seeing halos around lights, and double vision in one eye. Risk factors for cataracts include: old age, living in a tropical or desert area with large amounts of sunlight, diabetes, a family history of cataracts, certain drugs such as anti-inflammatory steroids, and smoking (3). Some experts claim that many cataracts are caused by excessive lactose (milk sugar) and sucrose (table sugar) (4).

            Glaucoma is usually a slow and painless loss of peripheral (side) vision, which may eventually result in total vision loss. It affects about two percent of all seniors in America (3). Glaucoma occurs when there is blockage in the eye that prevents fluid drainage. Pressure then builds up that can damage the optic nerve. If the optic nerve is significantly damaged, vision loss and blindness will result. Risk factors for glaucoma include: middle age and old age, family history of glaucoma, extreme nearsightedness, diabetes, and African American or Native American ethnicity (3).

There are a number of different medications that are used to treat eye problems. The side effects are listed below only for the medication being used in the eye itself (ocular administration).

Anesthetics (ex. Lidocaine): relatively safe 

Antibacterials: can cause allergic reactions

Antifungals: relatively safe

Antivirals: Viroptic (Trifluridine) can raise intraocular eye pressure and also scar the white of the eye (conjunctiva)

Steroid Anti-Inflammatories: can raise intraocular eye pressure, cause cataracts, cause susceptibility to infection, and can blur vision

Non-Steroidal Anti-Inflammatories (NSAIDS): relatively safe

Ocular Decongestants: can cause glaucoma 

Antiallergy: relatively safe

Pupil Dilators: increased intraocular pressure, glaucoma

Sodium Chloride solutions: can have thimerosal as a preservative. Thimerosal is 50% mercury, which can cause allergic reactions, among other things 

Glaucoma medications, mitotics: nearsightedness, poor night vision, cataracts, retinal detachment

Glaucoma medications, stimulants (Alpha-adrenergic agonists): (paradoxical) glaucoma, allergy

Glaucoma medications, carbonic anhydrase inhibitors: allergy 

Glaucoma medications, antimetabolities: retinal toxicity, cataracts 

            Fortunately, there are several nutrient supplements that can help prevent, slow, or even reverse many different eye problems. There is evidence that nutritional supplements can help slow macular degeneration, such as beta-carotene, vitamin C, vitamin E, zinc, and copper (1). There is also evidence that many people need to supplement with various vitamins and minerals in order to maintain eye health. Vitamin B2 (riboflavin) deficiency may be linked to macular degeneration and cataracts (5). Also, low levels of zinc (6) and selenium (7) may contribute to macular degeneration.

            One of the most important nutrients for proper eye function is vitamin A. Vitamin A actively helps maintain the outside of the eye (the cornea) (2). It is needed by the retina to help process visual light for electrical transmission by the optic nerves. Vitamin A is especially important for night vision. In animal studies, experimental deficiencies of vitamins A and E can cause retinal degeneration; also vitamin C may protect against sunlight-mediated retinal damage (3). Unfortunately, too much vitamin A supplementation can be toxic to the liver. Beta-carotene, the precursor to vitamin A, is a safer supplement to take on a daily basis. It is found in red, orange, and yellow vegetables, whereas vitamin A is found in animal products. A Finnish study showed that people with low levels of beta-carotene were almost twice as likely to have a cataract (8). Conversely, people who supplemented with at least 8700 IU/day of beta-carotene reduced their risk of macular degeneration by half (9). 

            There is much evidence that supplementing with vitamin C can help prevent the development of cataracts. Concentrations of vitamin C in the front of the eye are 10-30 times the average vitamin C concentration in the rest of the body (9). Vitamin C supplementation of 300-600 mg/day can reduce cataract risk by 70% (9). In fact, Vitamin C supplementation for more than ten years can reduce the risk of cataracts by 45% (10). Vitamin E may also be beneficial in preventing cataract formation. 400 IU/day of vitamin E can reduce the risk of cataracts by half (9). However, there may be some danger in supplementing with 400 IU/day or more of vitamin E (11). Also, 400 IU/day of vitamin E may accelerate certain vision problems (9), so it may be better to supplement with 200 IU/day of natural vitamin E (mixed tocopherols). Look for labels that say alpha, beta, gamma, and delta tocopherols are included in the bottle. 

            Do not buy liquid vitamins from a bottle, because they can go rancid (even in the refrigerator), and may actually be worse to take than nothing at all. Make sure the liquid vitamins are either in a capsule, a dry tablet, or are in powder form, like vitamin C crystals. Refrigerate liquid vitamin capsules such as vitamin E and beta-carotene to keep them fresh. If someone is thoughtful and disciplined in their diet and lifestyle, they can often slow or even reverse eye disease. It’s not inevitable that everyone slowly loses their vision as they grow old; as you have read, there are many natural ways to help the eyes maintain or regain their health.

References:

1. Litin, S., ed. Mayo Clinic Family Health Book, 3rd Ed. New York, NY: HarperCollins Books, 2003.

2. Reavley, N. The New Encyclopedia of Vitamins, Minerals, Supplements, and Herbs. New York, NY: M. Evan & Co., 1998.

3. Cassel, G., Billig, M., & Randall, H. The Eye Book: A Complete Guide to Eye Disorders and Health. Baltimore, MD: Johns Hopkins University Press, 1998.

4. Balch, P. Prescription for Nutritional Healing, 3rd Ed. Avery Books/Penguin Putnam Inc., 2000.

5. Leske, MC, et. al. (1995). Biochemical factors in the lens opacities. Case-control study. The lens opacities case-control study group. Archives of Ophthalmology, sep, 133(9): 1113-1119.

6. Mares-Perlman, JA, et. al. (1996). Association of zinc and antioxidant nutrients with age-related maculopathy. Arch Ophthamol, Aug, 114(8): 991-997.

7. Tsang, NC, Penfold, PL, Snitch, PJ, & Billison, F. (1992). Serum levels of antioxidants and age-related macular degeneration. Doc ophthalmol, 81(4): 387-400.

8. Knekt, P., Heliovaara, M., Rissanen, A., Aromaa, A., & Aaran, R. (1992). Serum antioxidant levels and risk of cataract. British Medical Journal, Dec 5, 305(6866): 1392-1394.

9. Feinstein, A. Healing with Vitamins. Emmaus, PA: Rodale Books, Inc., 1996.

10. Hankinson, SE, et. al. (1992). Nutrient intake and cataract extraction in women: a prospective study. British Medical Journal, Aug 8, 305(6849): 335-339.

11. Miller, ER, et. al. (2005). Meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality. Annals of Internal Medicine, 142(1): 1-11.

 

Dr. Jensen is both a consultant and author in the BioMedical and Nutrition fields. He has previously written a book on both topics, The Failures of American Medicine, published in 2002. Dr. Jensen has also written a doctoral dissertation on how Vitamin C can reduce stress and allergies via its antihistamine effect. He has worked in a broad range of BioMedical fields, such as gene regulation, cancer research, and HIV vaccine development. However, Dr. Jensen eventually decided that helping people more directly would be more rewarding for everyone involved. He has since helped clients with dozens of different ailments. Dr. Jensen is a practitioner in the field of Metabolic Typing, which characterizes different biochemistries among people based on certain physical and behavioral traits they have.

You can contact Dr. Jensen at 1-800-390-5365, or mail him at drjensen@individualizednutrition.com.

Article Source:http://www.articlesbase.com/vision-articles/eyesight-problems-1061435.html

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