ElderWeb

Have you ever wondered why your glasses sometimes seem inadequate even when you just had your prescription checked? Results of a recent study indicate that "real world" vision in seniors may be worse than traditional eye tests indicate, and that a significant proportion of the older population may be legally blind in poor lighting conditions.

John Brabyn PhD, Directory of The Smith-Kettlewell Eye Research Institute (SKI) Rehabilitation Engineering Research Center for Blindness and Low Vision, presented results from the SKI study of vision in seniors at the annual American Society on Aging / National Council on Aging Conference in San Francisco, California. Dr.Brabyn pointed out that traditional vision tests measure vision under ideal conditions -- using high contrast black text on a white background and in good lighting conditions. On the other hand, the "real world" consists of many situations where people see low contrast information in low light or glare. For instance, information on LCD screens used in electronics, ATMs, appliances, and elsewhere consists of black text on a gray or green background, which is much harder to see than black text on a white background. Street signs are often seen against the glare of the sky, electronics often have black buttons on a black control panel, and all these situations make information much harder to see than in the ideal conditions of a doctor's office.

Many other vision studies exclude users over the age of 75, making it difficult to assess the impact of vision changes on older people, so the SKI study deliberately included a high percentage of older adults, including many over age 85. The study then evaluated vision for a broad age-range in "real world" conditions. Results indicate that glare, dim light, and contrast decrease vision in older people significantly more than for younger people. Researchers found that many older people who tested for normal vision using traditional tests became nearly blind when low contrast, glare, and/or low light were introduced. The impact of these additional factors varied significantly by age, with little impact to those under age 75 but exponentially increasing impact on those age 75 or older.

Dr. Brabyn indicated that someone age 85 or older with "normal" vision could have vision reduced to 20/200 (legally blind) in certain "real world" situations. He said a large percentage of the older population is legally blind in poor light conditions, maybe 70% if you add in low contrast and glare. Even those with good acuity are impaired in low contrast and glare and need a drastic increase in magnification to compensate, up to 125 times more than their "official" acuity would indicate.

What does this mean to seniors and those who work with them? It may be even more important than was previously realized to increase contrast, improve lighting, and reduce glare to ensure that older adults can discern signs and other critical textual information. In cases where those factors cannot be controlled, older adults may benefit from tools used by the blind that can read or speak information they cannot see.

Researchers presented information about new technology to help blind and low-vision people find their way around public places at the American Society on Aging / National Council on Aging annual conference in San Francisco.

Jim Marston, PhD, Research Unit on Spatial Cognition and Choice, Department of Geography, University of California, Santa Barbara discussed problems faced by visually-impaired people negotiating public transportation systems. Dr. Marston began studying the problems of using public transportation systems when he lost his ability to drive due to his own declining vision. He found that public transportation systems are especially confusing and disorienting to people with little or no vision.

This is a problem that will be encountered by others in the aging population, since many older people will eventually reach a point where they can no longer drive, and many seniors may effectively be blind in real world situations like public transportation (see related story in the sidebar).

As a solution to those problems, Jim Marston, PhD, Research Unit on Spatial Cognition and Choice, Department of Geography, University of California, Santa Barbara and C. Ward Bond, President, Talking Signs, Inc, Baton Rouge, LA described Talking Signs?. Talking Signs? technology is an infrared wireless communications system that provides remote directional human voice messages that make confident, independent travel possible for vision impaired and print-handicapped individuals. The technology was pioneered and developed at Smith-Kettlewell Eye Research Institute, Rehabilitation Engineering Research Center in San Francisco, California.

Using this technology, infrared transmitters are placed on signs and in other strategic spots and "read" with handheld readers carried by the visually-impaired. Each infrared transmitter sends details that make the information on the sign meaningful to someone who can't read it. For instance, an infrared transmitter on the front of a train might tell the name of the train and its destination, a transmitter on an exit sign might include instructions on which direction to turn to get to the exit.

Dr. Marston took blind people into public transportation sites like CalTrain and BART stations and asked them to find their way to a specific gate, find bathrooms and amenities, and so forth. Most of his subjects had to resort to asking for help. He then had them negotiate the same station using Talking Signs? and found that they had significantly improved rates of success, generally without needing to ask for help.

The developers see several advantages in this system over either Braille or loud speaker systems.

The message is specific to the user, not broadcast to the public. This makes it possible to tailor the information with instructions about which direction to turn.

The message can be delivered in any language, again tailoring it to the user.

The user does not have to get right next to the sign to know it is there and read it, the sign can be "read" from as much as 100 feet away.

If there are several signs in an area, only one, the one the reader is pointed at, is "read" at a time, reducing the confusion that would ensue from numerous simultaneous loud speaker messages.

The technology has been installed in hundreds of places in several countries already, and the company has plans to add new features, including a "hands-free" headset receiver, and an all-inclusive handheld device that would consolidate a receiver with a cell phone, PDA, GPS, and compass.

With greater life expectancies and increasing demand for improved quality of life, the number of very elderly people receiving cataract surgery has been projected to grow substantially in the coming years. Tien Yin Wong of the National University of Singapore published a research in the British Medical Journal to provide an estimate of the impact of increasing age on the safety, benefits, and risks of cataract surgery. He makes several points:

Co-morbidity (the existance of other clinical conditions or diseases) is clearly a factor in both the success of the procedure and the likelihood of adverse reactions, and co-morbidity is much higher in the older population.

The presence of concomitant cardiovascular diseases results in higher risk of complications, and a substantial proportion of very elderly people will have concomitant cardiovascular diseases, with many of these diseases undiagnosed before cataract surgery.

Previous studies show that people with age related maculopathy, glaucoma, or diabetic retinopathy were twice as likely not to improve after cataract surgery, compared with those with none of these conditions.

The possibility that age may be used as factor by insurance companies or public benefit programs in determining whether surgery will be allowed and paid for is a sensitive and controversial topic, and it should be approached objectively and scientifically.

A study pooling results from several eye disease studies conducted on three continents shows that tobacco smoking is the principal known preventable risk factor associated with age-related macular degeneration (AMD). The study, analyzing combined data from studies conducted in Beaver Dam, Wisconsin; Rotterdam, the Netherlands; and the Blue Mountains area, west of Sydney, Australia; shows that apart from age, tobacco smoking is the only risk factor consistently associated with any form of AMD in each study location and overall.

The study appears in the April 2001 issue of Ophthalmology, the clinical journal of the American Academy of Ophthalmology, the Eye M.D. Association.

The New Mexico Motor Vehicle Division has announced the availability of a more comprehensive, online vision test. The online eye exam is available only at motor vehicle offices in Albuquerque, Santa Fe and two other cities, but by but eventually will become available to anyone with a computer video-conference camera. The online eye exam tests for long-distance vision, night vision, peripheral vision and color blindness, a more comprehensive vision test than that required by New Mexico law to be able to drive. Gorden Eden, director of the state Motor Vehicle Division Eden said the more comprehensive eye exam should improve highway safety by testing elderly drivers more thoroughly, saying, "The aging driver is becoming a greater risk than male teens."

The Food and Drug Administration (FDA) announced the approval of two new drugs, Lumigan and Travatan, to treat the elevated intraocular pressure which is often associated with glaucoma. These drugs are intended as additional alternatives for the reduction of intraocular pressure in patients who are intolerant of other intraoular lowering medications, or in patients who have had insufficient responses to other intraocular pressure lowering medications. Many of these patients might otherwise need surgery for management of their glaucoma.

Glaucoma, a leading cause of irreversible blindness in the world, is the second most common cause of blindness in the United States and affects about two million older Americans. Lumigan will be marketed by Allergan, Inc. of Irvine, California. Travatan will be marketed by Alcon Universal, Ltd of Fort Worth, Texas.

A recent issue of the British Medical Journal (BMJ) included an interesting history of the theories about longevity. The Journal, in an article which is easily understandable by both professionals and consumers, discusses the way that theories on "how to live forever" have changed over time. For instance, BMJ points out that people have known for years that eating roasted meats is unhealthy. Now we avoid roasted meats because of the artery clogging effects of cholesterol and the carcinogenic qualities of nitrosamines in the charred parts, but the theory some time back was that consuming roasted food used up too much body energy in the way that a gas burner uses up gas more quickly when the flame is turned up high. The article talks about ways that "fountain of youth" qualities have been attributed to a wide variety of food, drink, and lifestyle issues, like maintaining body heat and moisture, avoiding wine, sleeping on your right side, and taking rhubarb pills.

The British Medical Journal (BMJ) reports on a promising treatment for macular degeneration. They report that clinical trials showed that photodynamic therapy with verteporfin could reduce the risk of moderate and severe vision loss from 61% to 33% at one year and from 69% to 41% at two years in patients with neovascularisation extending under the centre of the retina and predominantly classic appearances on fluorescein angiography -- an appearance that has a high likelihood of growth and vision loss within months if left untreated.

They state that approximately 20% to 30% of the 200,000 cases of neovascular macular degeneration that present to ophthalmologists in the United States each year are candidates for prompt photodynamic therapy. Once extensive vision loss has occurred the treatment is no longer beneficial. It is important therefore to teach older patients with drusen who are at risk of developing neovascular macular degeneration to screen for the possible development of neovascularisation.

The Food and Drug Administration (FDA) has approved a new surgical alternative to a hearing aid. The Vibrant Soundbridge is a surgically implanted hearing device intended to help adults with moderate to severe nerve hearing loss. The device is implanted behind the ear in the temporal (skull) bone. It converts sound to mechanical energy that is transferred to the middle ear, which vibrates the structures in the middle ear the way normal sound does. During the implant surgery, the surgeon implants a receiver behind the ear. A wire leads from the receiver to a small electromagnet attached to one of the middle ear bones.

In the US study, 81 patients who were followed up for at least 9 months were tested first with hearing aids in both ears and then with the implant in one ear. The results showed that the participants could hear about as well with the implant as with traditional hearing aids. One warning the FDA points out is that patients with the Vibrant Soundbridge may not have Magnetic Resonance Imaging (MRI) of any type because the Vibrant Soundbridge has an implanted magnet that is a potential safety problem, since the magnetic field of the MRI could dislodge the implant

When an elderly person suddenly slips and falls, it may be called an accident and blamed on old age. But researchers in California suggest such falls could in fact be the result of disorders of the inner ear. Dr. Gail Ishiyama, a neurologist at the University of California, Los Angeles, says her research indicates that some falls can be traced to Meniere's disease and related disturbances of the inner ear, and to call these falls "accidental" could result in the patient's receiving the wrong sort of treatment while the real cause remains untreated.

The Food and Drug Administration (FDA) announced the approval of verteporfin for injection (Visudyne), the first therapy to slow vision loss in people with the classic type of Wet Age-Related Macular Degeneration (AMD). AMD, a retinal disease causing severe and irreversible vision loss, is a major cause of blindness in individuals older than 60 years in the Western World. In AMD the central field of vision is impaired while the peripheral or side vision is unaffected.

90% of AMD is the "dry" form and only 10% is the "wet" form, but the "wet" form destroys vision more quickly. Untreated, the majority of eyes affected with wet AMD will become functionally blind within two years.

Visudyne therapy is a two-step combination drug and device treatment process. It is relatively painless, takes about 20 minutes, and can be performed in a doctor's office.

Paul T. Finger, M.D., an Associate Professor of Ophthalmology at the New York University School of Medicine, has created extensive patient information sites on macular degeneration and eye cancer. His sites provide a wide variety of disease and treatment information for patients, all in extra large type.