Lowvision Causes of Lowvision Lowvision exam Lowvision devices Lowvision aids Vision rehabilitation

What is low vision?
Low Vision is a visual impairment that is not correctable by standard glasses, contact lenses, medicine, or surgery that interferes with a person's ability to perform everyday activities.

What causes low vision?
Low vision can result from a variety of diseases, disorders, and injuries that affect the eye. Birth defects, injuries, certain diseases of the body and aging all may lead to loss of sight. Most commonly, it is due to scarring because of deterioration of the central part of the retina (the light-sensitive tissue that lines the back of the eye). Many people with low vision have age-related macular degeneration, cataract, glaucoma, or diabetic retinopathy. Age-related macular degeneration accounts for almost 45 percent of all cases of low vision.

How many people have low vision?
About 135 million people around the world have low vision.

How does low vision affect people's lives and their routines?
People with low vision experience physical, economic, and psychological changes that diminish their quality of life. Low vision affects daily routines (walking, going outside, cooking), leisure activities (reading, sewing, traveling, sports), and the ability to perform job-related functions that can lead to loss of income. These consequences often lead people with low vision to become confused, miserable, fearful, uneasy, and depressed. In addition, these people who lose their depth perception are at greater risk of falling and injuring themselves.

Are people with low vision more prone to accident and injury?
Evidence suggests that the loss of stereoscopic vision and depth perception increases the chances of falling, tripping of the low vision patients, and they are at more risk than the ordinary people.

What should a person do if he or she has low vision?
First they should note the kinds of vision problems that are occurring. Some warning signs include the following:
  1. They may feel trouble to read, cook and in other daily activities.
  2. Problem in seeing because the lights don't seem as bright as normal
  3. Problem in distinguishing the faces of friends and relatives
  4. Problems during crossing the road and reading the traffic signs.
A person who is having these vision difficulties should immediately make an appointment with an Ophthalmologist for an eye examination. If the person's vision cannot be treated by conventional methods, such as glasses, contact lenses, medication, or surgery, then he or she should ask the Ophthalmologist for information about vision rehabilitation. These services may include eye examinations, a low vision evaluation, training on how to use visual and adaptive devices, support groups, and training on how to perform everyday activities in new ways.

What should a person do if he or she knows someone with low vision?
Urge that person to make an appointment with an eye care professional for an eye examination. Then help the person find out about low vision and vision rehabilitation services and encourage him or her to take advantage of all available resources.

How does a low vision exam differ from a regular eye exam?
A regular eye exam concentrates on diagnosing eye disease. A low vision examination focuses on designing specialized glasses and low vision devices to enhance remaining vision. A low vision exam, sometimes called a functional vision assessment, evaluates vision functioning and the effect it has on daily living activities, such as reading the newspaper or cooking. After an interview helps to determine the person's visual goals, a low vision specialist performs a detailed visual analysis. Distance vision is evaluated using telescopic aids. High-powered microscopic spectacle lenses, telemicroscopic aids and hand or stand magnifiers may be used to evaluate near vision skills, like reading. Special eye charts are used and lighting levels are evaluated. This analysis can take as long as one hour. In addition, instruction in the proper use of devices can take hour and may be repeated before aids are prescribed. Many agencies provide a loaner program so individuals can borrow aids to try them out. After the vision exam, the individual may be referred to other professionals who work with visually impaired persons, such as mobility instructors.

Can a regular ophthalmologist or optometrist do the low vision exam?
Presently, fewer than 5% of all eye doctors specialize in low vision. Though there are some ophthalmologists who specialize in low vision, most low vision specialists are optometrists. Effective low vision rehabilitation requires expertise and technology for the thorough evaluation of visual function as well as full access to available optical and electronic low vision devices. Additionally, the Center offers a comprehensive rehabilitation program, including counselling and instruction in independent living and safe travel skills that is not offered by ophthalmologists or optometrists.

a) Can I have low vision and not be legally blind?
b)If I have low vision, does that mean I cannot drive my car?
It depends. Your eye doctor can tell you.

What does a low vision specialist do?
  1. Takes a careful and methodical history of your visual difficulties with emphasis on your current problems.
  2. Checks and records your current prescriptions.
  3. Performs a refraction of your eyes to determine your best prescription.
  4. Determines which low vision devices can help you to function better for distance and reading.
Low vision devices that might be prescribed:
  • Special purpose bifocals
    For computer use, hobbies or your occupation.
  • Microscopes
    High power reading glasses, for use with one or both eyes, may enable you to read normal size print more easily.
  • Telescopes
    High power devices for looking at faces across a room or street, reading signs or computer screens or watching television. They can be used with one or both eyes. They can be either hand held or in glasses.
  • Hand magnifiers
    Are helpful for reading price tags, menus, thermostats, stove dials, etc.
  • Sunglasses / filters
    Many people with vision disorders are light sensitive. Special filters may enhance their comfort and function.
  • Electronic magnifiers
    For patients who cannot read satisfactorily with glasses, certain devices can play print back on a screen at a size and speed you choose.
Most patients with congenital (from birth) or acquired vision loss can be helped with low vision aids.

             Dome Magnifier

 Glass with Binocular telescope

               Hand Magnifier
What is a Low Vision Clinic?
A Low Vision Clinic is a specialized centre established to offer people with serious visual problems the benefit of scientific aids which are designed to maximize remaining vision whenever possible.

Who can benefit from Low Vision Clinic services?
Any person who has enough remaining vision to see newspaper headlines held at any distance within arm's length has a good prospect with special lenses. The amount of benefit gained will depend on remaining vision, one's motivation, goals or objectives.

How are the people helped by the Low Vision Clinic?
A full assessment is made of the health of the clients' eyes and the degree of remaining sight. Knowledge of one's specific disease is important but what one sees and how much vision are much more important. Special visual aids to enable more efficient use of remaining vision are prescribed and supplied at the clinic. Through Low Vision Clinic services, vision is improved, not restored.

a) What are Low Vision Aids?
Low vision aids are special lens systems, which provide the magnification necessary to improve vision that is no longer correctable with conventional glasses, contact lenses or medicine. However, they are of no assistance to persons who only distinguish light from dark, or only have shadow movement vision

b) How can anyone in need of help come to the Clinic?
A person with a serious visual disability which affects daily activities at home or on the job can contact the Clinic personally or through his or her Ophthalmologist or Optometrist.

c) Who serves you at the Clinic?
Volunteer Consultant Ophthalmologists, Optometrists and Vision Rehabilitation specialists can give their services.

      Stand Magnifier
How can a Low Vision Patient function independently?
Low vision aids, counseling and rehabilitation services will help the person to regain the sense of independence. Optical aids include prescribed devices often specially created by the doctor to help reach an individual's visual goals. Electronic devices, such as the closed circuit television (CCTV) or computer software, enlarge print or pictures on a screen.
Non-optical vision aids include: signature or check writing guides; large print checks and calendars; talking calculators, talking watches and alarm clocks; and talking scales or thermometers, to name only a few. Independent living skills training, done in the person's home or in a class setting, and mobility training in the person's community or office setting, all contribute to this sense of independence.

Can all these aids help a person to remain independent?
So much information is communicated visually - signs, textbooks, menus, sales receipts, etc. Visually impaired people struggle with communication barriers that prevent them from gathering and using information. By helping people include remaining vision in their repertoire of resources, low vision devices coupled with Rehabilitation Techniques do allow individuals with vision loss to work, to shop, to study and to perform daily living tasks independently.

Does modern technology help visually impaired people?
Magnification, contrast and lighting can help maximize a person's remaining sight. New technology allows a person to control the size of the print they are reading, to adjust the contrast and color, and increase the brightness. For example, the closed circuit television (CCTV) allows the user to project any document or picture on to a screen and to magnify the document and adjust the contrast. Hand-held scanners and head-mounted devices perform a similar function as the CCTV, but use small cameras to place an image in front of your eyes or on a portable LCD screen. Large print and screen reading programs for computers are a tremendous resource. Advances in lighting technology have helped, as well.

Does stronger glasses make my vision better?
Glasses are only able to focus the picture for your eye. If the retina is damaged from macular degeneration or other diseases it is like having bad film in the camera and changing glasses won't make objects clearer. Glasses of any type whether strong or light won't help because stronger glasses don't allow you to see well in the distance. However, very strong reading glasses may allow you to see small print that is held very close to your eyes.

Can I get glasses to help me see better when I drive or help me get my drivers license?
Glasses can improve the vision of people whose vision problem is nearsightedness, farsightedness or astigmatism. Even the best glasses cannot overcome vision problems caused by eye diseases like macular degeneration, and therefore better glasses don't allow you to see down the road better. Some states allow people to drive wearing specially made telescopes called bioptics that are mounted on glasses but are only used momentarily for spotting distance detail.

   Aspheric glass
Does it hurt my eyes to sit close to the TV?
No. Physical harm cannot be done to the eyes by sitting close to a television set. Even sitting at 1-3 feet is o.k. Radiation or other damage does not occur and more detail can often be seen because as you sit closer the picture is bigger.

Can I damage my eyes by using them a lot or if I'm straining to see? They often feel uncomfortable when I work so hard to see things.
You cannot overuse your eyes. They may feel uncomfortable or strained due to tiredness and your eyes will not be damaged. You may not be able to use them for as long duration as you once did, but no harm will be experienced from use. Resting and sometimes using lubricant eye drops, as often as you feel the need, will allow you to resume visual activities and your eyes will feel better. Generally stamina improves with persistent practice.

Do I still need to see my other eye doctor?
Even if you were referred to a vision rehabilitation specialist, you still need to see your regular eye doctors who are providing general care or treating specific medical/surgical eye problems. The rehabilitation specialist helps you do the most with the vision you have, with adaptive techniques, devices and training. Your other eye doctor tries to help maintain the vision you have with medical treatment or surgery. Both types of care may be going on at the same time.

I sometimes have a sensation of seeing things that aren't there. Is that a dangerous sign about my eyes or is there something wrong with me mentally?
This is very common occurrence in people who have lost some vision. You may see colorful geometric patterns, people, animals or elaborate scenes anywhere you look and although they look real, you know they are not. This experience is often called phantom vision and the medical term is Charles Bonnet Syndrome. It is believed to be similar to phantom sensations that some people experience after limb loss. Charles Bonnet Syndrome is not an indication of worsening eye disease or of mental illness. It tends to become less frequent over time and rarely requires any treatment.

Why are parts of words missing and some small objects hard to find when I put them down? Sometimes I can see very small things, which puzzles me and other people.
Our central vision allows us to see what we look at directly and our peripheral vision allows us to see out of the corner of our eyes. Some eye conditions, including macular degeneration, cause blind spots or blurry areas in our central vision but leave peripheral vision intact. This means that out of the corner of your eye, your good peripheral vision may spot a small button on the floor, but the blurry area in your central vision, makes it disappear when you go to pick it up. If the blurry area or blind spot is small, you may see part of a word, or if you have several small blind spots words may pop in and out of your view.

Can I get a bigger strong magnifier so I can see more at one time? I can't see enough with this small lens.
In general the bigger the magnifier the weaker it is, and the smaller the magnifier the stronger it is. This is because strong magnifiers are very thick and cannot be made very large. Training and practice allows you to use magnifiers, even small ones, more effectively. Electronic magnifiers with screens offer strong magnification with a larger area of view.

Why can I read when I am using high power lights but I can't with a low power one? Can I use a 200-watt bulb.
Higher watt bulbs alone do not necessarily make it easier to see print or perform other tasks. The type of bulb and direction of light is important. A low watt floodlight bulb in a gooseneck lamp, for example, is usually better than a high watt bulb in a shade lamp because the gooseneck lamp directs the light onto the print while the shade lamp beams its light in all directions. Different kinds of bulbs may provide optimal light, for example fluorescent, halogen or Chromolux. Low vision rehabilitation offices usually have optimal lighting, which you can also place in your home.

Why can't I buy a magnifier at the store that will help me?
Most over the counter magnifiers are of low power and usually lower quality. They are not designed to be used by people with more advanced visual impairments. Patients with very early loss of vision may find help with this type of device. As the vision deficit becomes more severe the type and power of assistive device is better determined by an experienced low vision specialist who can match it to your vision level and needs.

Do I qualify for a benefit on my income taxes?
If you are "legally blind" (best vision of 20/200 or severe field loss, as determined by your eye doctor) you qualify for an additional deduction on your income tax.

How will using an eccentric viewing position help me?
The normal visual system positions your eye so the image you are trying to see falls on the center of the macula. If that part of the retina is damaged you see a blur (inability to recognize faces) or an incomplete picture (miss parts of a word or letters within a word). This is very disruptive to reading and writing and other daily activities. By moving the eye to a different position when the center is damaged, you can receive a more complete and clearer picture of what you are trying to see. This will help you perform many of your activities more easily and increase your success with assistive devices.

Why does it require so much training time and how long will it take?
Re-educating the eye and brain to perform fine detailed activities with a new retinal location is a complex task. It is reprogramming your biologic computer. Activities you performed automatically now require a new system to complete. Once learned however it will speed up performance and activities will be accomplished with much less frustration. Patients frequently don't achieve a breakthrough for 3 or 4 visits. The average number of visits to complete the program is six.

Can't I do the training on my own at home? Aren't there instructions on how to do it?
Practice can be done at home and it does make a difference in progress and success. Because this is a complex process and everyone learns differently and has a different set of problems, the training has to be individualized. Observation of the patient, particularly eye position and eye movements, requires an experienced and skillful teacher to maximize results and continue progress. When patients are frustrated and struggling, changing techniques or exercises and encouragement by the therapist can make a big difference. Correcting mistakes early can save time and promote more rapid progress.

Is my vision going to get better with all these exercises and training?
You may feel that your vision has improved because of gaining better visual skills and use of an eccentric viewing position. Seeing a more complete and clearer picture is a big advantage over what you experience when looking at objects with the damaged part of your macula. The benefit is from maximizing the vision you have, not from treating your medical condition.

How does tracing help me see better and do my daily activities? It seems like kindergarten work. What about other exercises?
Tracing may see very simplistic but you may have noted how difficult it is to perform accurately. This is a good measure of how well you can use your eccentric viewing position. The eye hand coordination and use of the new eye position will be a great advantage and benefit in performing many daily activities because of the clearer and more complete picture you will see. Repetitive exercises like tracing and identifying cards help to develop this ability. Exercises are designed to improve the visual skills needed to read, write and do many fine detailed tasks. It may also improve your handwriting legibility.

Why doesn't the therapist give me a magnifier to use on the first visit?
When you lose vision from a central scotoma (hole in your vision) that interferes with fine detail tasks like reading, enlarging print may make it easier to see print but harder to put letters and words in sequence. Seeing only a word or two with a magnifier can slow reading to a point of poor comprehension and make the process very frustrating. Some basic visual skills gained under the guidance of a therapist before using devices can increase your success.

What resources and strategies can help people perform daily tasks at home?
Resources and strategies depend on the severity of a person's vision impairment. At home, people need devices that can help them read, write, and manage the tasks of daily living. These adaptive devices include adjustable lighting, prescription reading glasses, large-print publications, magnifying devices, closed-circuit televisions, cassette recordings, electronic reading machines, and computers with large print and speech output systems. Simple strategies include writing with bold black felt tip markers and writing on tablets with bold lines to make it easier to write in a straight line. Also, contrasting colors are helpful: people can place colored tape on the edges of steps to help them see the steps and prevent a fall. Dark-colored light switches and electrical outlets can provide contrast on light-colored walls. Motion lights that automatically turn on when someone enters a room are helpful. Telephones, clocks, and watches with large numbers can help people use those instruments more easily, and large-print labels placed on the stove and microwave oven can help, too.
Among the visual devices that can help people with low vision are reading glasses with high-powered lenses and reading prisms; telescopes and telescopic spectacles for tasks requiring vision at near, middle, and far distances; and reversed telescopes for visual field defects. These devices must be prescribed by eye care professionals, and patients must be trained to use them properly.

What agencies and organizations provide people who have low vision with help and information?
Many agencies and organizations in the community provide assistance and information to people who have low vision, and to their families and caregivers. State agencies for the blind and visually impaired can make referrals to a variety of organizations that provide assistance. Such services include vision rehabilitation, recreation, counseling, and job training or placement.

Why aren't these resources used more often?
Many people don't know that help exists. They think of low vision as a natural part of aging, not as a problem that can be treated. Others feel that these services and devices are for people who are blind, not for people with low vision. Also, the cost of many devices keeps people from obtaining them. Finally, people may know that help exists, but they don't know what their options are and aren't sure how to ask for help or whom to consult.

What is vision rehabilitation?
Vision rehabilitation is a comprehensive set of services, including optometric, counselling and rehabilitation programs, that help people with low vision regain a sense of independence. Low vision optometrists help those with vision loss to see better, even when surgery, medications, and conventional glasses no longer improve sight, by designing and prescribing optical aids to help the person read, write, watch television and manage daily living activities. The vision loss is permanent but the ability to perform daily living tasks with impaired vision is learned or relearned through our rehabilitation program.

Vision loss is frightening. How can I cope?
A significant vision loss presents a challenge to everyone. You may feel alone. The Center provides a number of forums for individuals to meet with licensed clinical therapists to address emotional needs. Counselors meet with individuals and their families. Or, a person can participate in a support group with other partially sighted people to discuss needs, problems and successes. Additionally, rehabilitation programs teach daily living skills, such as safe travel in the community.