Despite advances in medicine, there are inevitably times when vision deteriorates to a point where, despite the best correction available, daily tasks can no longer be performed. Common areas of difficulty include: watching television, reading tasks, managing the kitchen safely or participating in hobbies and pastimes.
Definition of Low Vision
Someone is said to have low vision when their eyesight is unable to be improved to a functioning level with glasses, contact lenses or surgery. The disability can also involve reduced visual field, distorted vision or loss of contrast. The cause can be due to injury, inherited conditions such as Retinitis Pigmentosa or chronic progressive disease eg. macular degeneration or glaucoma.
Who is my first point of contact?
Attend a low vision consultant, specifically an optometrist who specialises in improving vision for those affected by various eye conditions. Your local Bunbury-based low vision specialist is:
Additionally, there are many organisations (eg. Association for the Blind of WA) who are also here to assist you with general lifestyle requirements, i.e. being able to live safely and comfortably in your own home.
A low vision assessment begins with taking a comprehensive history about your eyes, specifically when you were diagnosed with a particular condition and any treatment that has been given. Your ophthalmologist is able to provide the optometrist with this initial information. You will then be asked which particular tasks you would like assistance with, specific difficulties you are experiencing, and also any hobbies or interests that require visual assistance.
Your sight will be measured for glasses. These results will be compared against your current prescription. Sometimes a simple change in lenses is enough to bring about a valuable improvement in your vision. Changing lens design i.e. going from a multi or bifocal lens to separate distance and reading glasses, or increasing the lens size can often bring about valuable and worthwhile improvements in field of view and visual comfort too.
Your low vision specialist will emphasise the importance of good bright illumination, such as using an angle poise lamp directed from behind you to avoid issues with glare. This is a circumstance where eco-friendly fluorescent bulbs will not do the job adequately.
If glasses fail to improve vision sufficiently for specific tasks, the next step is to magnify the image. This is just the same as holding the image closer, except you are using a visual aid to achieve this. The downside to this approach is that every time you double the magnification of the image, you halve the field of vision. This will adversely affect reading fluency, as you cannot see and scan the letters ahead on the page. It will however, help you to read things that you may not have previously been able to manage such as bills, and documents or the newspaper.
The following are examples of visual aids, which may prove to be helpful:
- Reading magnifiers +/- in-built illumination.
- Small monocular and binocular loupes and telescopes, which may be useful for both near and distance tasks.
- Closed Circuit Television (CCTV) based devices.
- E books and Services.
Simple magnifying glasses and telescopes can assist with reading and distance tasks such as watching TV.
Electronic and CCTV-based devices are more sophisticated and more expensive
It is often helpful (and less overwhelming) to bring a family member along to these appointments to aid in the understanding of what options are available to you.
The Association for the blind of Western Australia may also be able to assist you by organising a home visit and providing solutions to problems you may be having in your day-to-day environment. Assistance here can include provision of items like talking clocks, talking books, adjustable lamps, and mobility aids.
Attention will be given to making your environment safe, particularly in the kitchen. Some practical tips include ensuring good lighting within your home, minimising glare and increasing contrast and sticking large-print labels on TV remotes and other household items. Advice regarding Webster packs for your medications can be given.
The Webster pack places medications in compartments for the different times of day, which simplifies things for the visually impaired
If you are profoundly blind and cannot navigate in the home or outdoors, you may be suitable to receive the services of a guide dog for the blind as well as having a new best friend for company.
These associations are able to put you in touch with support groups and government organisations which can also be of assistance. You will receive advice regarding eligibility for subsidies and entitlements. Under Australian legislation, being “legally blind” means having corrected visual acuity of no better than 6/60 and/or a vision field of no more than 10 degrees. If you are legally blind then you are entitled to the full rate of Age Pension if you are at the correct age, or Disability Support Pension if you have not yet attained your Age Pension age. There is no means or asset testing in this circumstance. You may also be entitled to travel subsidies and the option to apply for LotteryWest (in WA) means-tested grants for adaptive technology eg. computer software.
- Contact your local library for large print and talking books – they may also have facilities such as digital readers.
- Online services for e books with enhanced font size and contrast etc www.readeasily.com
- www.aisquared.com is a great site with many enhancements for home computers and other devices
- Check out this great mouse-magnifying device that you can use to enhance your home computer
- The MD_evReader is an iPad app that uses static eccentric fixation techniques and a “ticker tape ” text so that those with low vision do not have to track and fixate. eBooks can be downloaded and read in this format, either from the iPad or from a remote screen.
By definition those with low vision have some vision to enhance. Some are unfortunate in having no useful vision whatsoever. These are the people who need a new technology to rehabilitate their visual status.
You may have heard about “Bionic Eyes” in the media. Research has reached the human trial stages with some success. The technology is similar to the Cochlear implant; sensors are placed in the eye, which then transmit an electronic signal to the brain. There are about 1.2 million nerve connections in the healthy eye, so replicating this is complex. It is entirely reasonable to suppose that in the coming decades there will be devices available that give people back their navigational vision, and who knows what more time and technology may bring.
For those with inherited retinal diseases there are human trials underway with gene therapy, which actually corrects the miscoded genes in the retina.
For those with corneal blindness, there are devices called Keratoprostheses or “Artificial Corneas” that are already giving people back their sight. These may have a telescope device within them. The K-Pro device was designed and trialed at our Lions Eye Institute here in WA.
Whatever the cause of your low vision, the main message is that you are not alone and there are many people who can help you. Don’t be afraid to ask for this assistance. Also be aware that low vision can carry with it an increased incidence of depression, so if you find yourself depressed you should discuss your feelings with family, your GP or other health professionals. Continue your regular visits to your ophthalmologist and optometrist too and you will then be giving yourself every chance for your best possible vision.