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Continuing Our Work During COVID-19

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Linda S. Petty, Adaptive Technology Resource Centre (ATRC), University of Toronto
Paper presented at the Technology and Aging Conference, Sept. 12, 2001, Toronto ON.
posted October 24, 2002

Linda S. Petty, B.Sc. OT, OT Reg. (Ont.)
Coordinator, Vision Technology Service
Adaptive Technology Resource Centre,
University of Toronto
Toronto, Ontario, Canada


Trends in Aging and Visual Impairment

As reported in the National Action Coalition on Aging report " 1999 and Beyond", for most seniors, Canada is a good place to grow older. Canadian seniors live longer and in better health than seniors in many other countries. The aging of the population is no passing trend-here today, gone tomorrow. With people living longer and families having proportionately fewer children, seniors' larger share of the population-eventually reaching one-quarter of all Canadians-will remain for the foreseeable future. 1

Year Number Population share
1998 3.7 million 12.3%
2016 5.9 million 15.9%
2021 6.9 million 17.8%
2041 9.7 million 22.6%

One of the impacts of aging on our society and Canadian seniors will be the decrease in visual function associated with eye conditions common in aging. Presbyopia affects everyone sometime after the age of 40. As the eye ages, the lens becomes less flexible and can no longer easily focus on near objects or small print, however, this can be accommodated with glasses or contact lenses. Serious visual impairment is a result of major eye diseases that tend to affect people later in life. Data on the current age distribution of visually impaired individuals indicates that 38.1% of people became functionally visually impaired after their 64th birthday. Visual impairments that occur among older adults include: macular degeneration, glaucoma, diabetic retinopathy and cataracts.

  • Macular degeneration causes 45% of all visual impairments. It is the most common cause of blindness in Canada, accounting for 33 to 34% of the total incidence. It is caused by damage or breakdown of the macula, the part of the retina that provides clear, sharp central vision. It may occur in one or both eyes. Age Related Macular Degeneration (ARMD) is the most common cause of blindness in the aging population. The disease results in a slow, progressive loss of central vision.
  • Glaucoma affects 7% of seniors. It is a group of eye diseases caused by abnormal pressure within the eyeball. If the pressure is not relieved it can result in blindness. It is a silent disease, often un-detected until an eye exam. It is also linked to genetic factors.
  • Diabetic retinopathy is a possible complication of diabetes. It is present in 90% of those who have had the disease more than 20 years. It occurs when the retina does not get enough oxygen. Symptoms include retinal bleeding and fluctuating vision. Diabetic retinopathy blinds 400 Canadians every year.
  • Among seniors, 6% experience vision loss as a result of cataracts. Cataracts are thickened, hardened and cloudy parts of the eye lens. The cloudy lens blocks or distorts light coming into the eye and blurs vision. Cataracts can develop in both eyes and develop at different rates. Cataracts are generally correctable with surgery, however, when they occur in conjunction with other eye conditions or if there are surgical complications low vision can result.2

Effect of Visual Impairment on Reading and Writing Tasks

While vision loss has an obvious impact on personal mobility and driving, one of the greatest effects is the decreased ability to read and write. Reading bills and financial reports, leisure or work related material, letters, recipes, prices, newspapers are all everyday reading needs that can become difficult or impossible to perform. Likewise, jotting notes, writing cheques and letters, word processing, writing email or other productivity or leisure related documents becomes difficult to see, edit and review. While many seniors are using the Internet extensively for research and communication, finding the mouse cursor, reading text and seeing web documents can become problematic. The standard accommodation of employing bifocals, half reading glasses, or the 2X to 4X magnification glasses found in drug stores, will generally only accommodate presbyopia, not more profound vision losses. Likewise, magnifiers are common low technology aids that are very helpful in spotting prices while shopping or finding where to write a signature, however, they cannot accommodate the more extensive reading needs experienced by most individuals.

High Technology Vision Aids

Thankfully, there is an ever-increasing range of high technology aids that can accommodate low vision- from the 20/70 acuity range- to full vision loss. While a more complete understanding of the various aids can best be achieved through the workshop as presented, the following summary highlights some of the available options. The items listed are the most commonly used type of equipment. The photographs included illustrate the type of product, but do not endorse the product shown.

Closed Circuit TeleVisions

image of a optelec clearview 317 closed circuit televisionA Closed Circuit TeleVision (CCTV) is a video magnification system consisting of a video screen interfaced with a video camera. Video magnification is achieved in two ways - the electronic conversion from the small camera imager to the larger display screen and the optical effect of the cameras zoom lens. The stand mounted CCTV\'s can be configured with television receivers, video monitors, or computer monitors. The CCTV system provides high contrast, inverse video display, gray scale, false colours, natural colours, and/or control of contrast level and brightness. CCTVs are ideal reading aids for handwritten material, and books or magazines and can enable users to read 3-D objects such as medication or food labels. CCTVs can be used to magnify the users own handwriting for cheques or letter writing. A range of CCTVs and information is available on the Internet at CCTV section of the ATRC Technical Glossary.

Computers as Reading and Writing Aids

While some non-computer users are hesitant to take on this relatively new technology, seniors of all ages have also embraced it. The computer becomes a communication tool for emailing friends and family, a window to the world through reading on the Internet, a financial management and cheque writing aid. Databases and word processors have all become friendlier tools in common usage. While the standard size font and display may not be visible with low vision, there are a variety of methods to make the computer into a reading and writing aid for those with visual disabilities.

Screen Magnification

image of a viewsonic 20 inch monitorThe initial method of visual accommodation is using the options available in the operating system to increase the font size, colour contrast and use the larger format displays. The next option is increasing the monitor size to 21 inches or larger. The next option is to add screen magnification software, often in conjunction with a larger monitor.The software enlarges the information on the screen by pre-determined incremental factor [for example, 1x magnification, 2x magnification, 3x magnification, etc,]. Magnification programs run simultaneously and seamlessly with the computer\'s operating system and applications. Most screen magnification software has the flexibility to magnify the full screen, parts of the screen or provide a magnifying glass view of the area around the cursor or pointer. These programs also often allow for inverted colours, enhanced pointer viewing and tracking options. The text, dialogue boxes, menus, etc., can also be read out loud by some screen magnification software, which can support text recognition, aid in fluctuating vision and help new users to understand what is being displayed and hear what they type. Many people with failing eyesight find the screen magnification software can enable them to continue to use a computer. The use of speech feedback integrated into the screen magnification software can accommodate fluctuating and progressive eye conditions up until the point of no light perception. An important resource for information on products in this area is the Screen Magnifiers homepage at

Screen Reading

To add to magnification, or to use for full auditory feedback of all computer functions, screen reader software with a software or hardware speech synthesizer is run in conjunction with any computer applications. The screen reader reads the contents of all documents and web pages, as well as talking you through standard computer functions like accessing menus, responding to dialogue boxes etc. The computer\'s numeric keypad is used to operate the screen reader and substitute for the mouse. Use of screen reading software enables people to write easily, hearing what they are typing, read back and edit work, save files, read email and web pages and generally obtain full use of the computer system. Current screen readers are not fully functional with very visual programs such as databases, but will work quite well with the major word processors, spreadsheets, email applications and web browsers. Links to screen reading product information are found at the Screen Reader section of the ATRC\'s Technical Glossary.

Scanner and Optical Character Recognition/Reading Software

With the plunging prices of flatbed scanners, using Optical Character Recognition (OCR) to translate printed material into electronic text has become very popular. Using a scanner, various pieces of small print or pictures, from mail, books, magazines, etc. can be viewed on the computer screen in magnification or read out loud. an image of a hewlett packard scanjet scanner Rather than manually bringing documents in with mainstream OCR software, many people with visual impairments prefer using OCR software with it\'s own speech feedback and magnification and text tracking features. This same specialized reading software can read documents downloaded from the Internet, where libraries of text files of non-copyrighted material are available for free. Web page files can be saved and read or even opened in an OCR program for ease of reading. Several companies have developed scan and read programs with simple interfaces designed to support the less experienced computer user in reading their printed material via the scanner and computer. For more information, consult the OCR Section of the ATRC Technical Glossary.

Services to Provide Equipment

While most people know to first see an ophthalmologist or optometrist for a prescription before ordering eyeglasses, the mechanism for obtaining an assessment for high tech vision aids is less commonly known. Service delivery and funding vary across Canada. Some provinces fund equipment for school or the workplace, but not for home use. The Assistive Devices Program of the Ontario Ministry of Health funds high technology vision aids for Ontario residents with low vision or blindness for up to up to 75% of the equipment cost. Equipment funded includes CCTVs, computer systems with screen reading and magnification software, scanners with Optical Character Recognition software and Personal Information Manager devices. Braille translation software and embossers are also available for those with Braille skills. Additional funds are available for individuals on social assistance programs through the Ministry of Community and Social Services.

The Vision Technology Service (VTS) at the University of Toronto is an ADP Regional Assessment Centre for both sight enhancement aids for low vision and sight substitution aids for full vision loss. The VTS also has occupational therapists who work in computer access and a range of alternative keyboards, trackballs and voice recognition software for assessments when concurrent physical impairments make standard keyboarding difficult. The VTS is located on the University campus in downtown Toronto and accepts referrals for Ontarians of all ages from across the province. For more information, call (416) 946-3225 or see the description of the service on the VTS website.

1 Health Canada document: Highlights 1999 and Beyond: Challenges of an Aging Society. Retrieved June 14, 2001 from the World Wide Web:

2 Health Canada document: Barriers to Seniors\' Autonomy: Sensory Loss-Vision. Retrieved June 14, 2001 from the World Wide Web: