Leber's Optic Neuropathy usually leaves an affected person with some useable vision. There are three aspects to making the most of this vision.
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| Monocular |
A monocular is a small (pocket-sized) telescope. There are several sizes of monocular available. I have seen a tiny 4x monocular mounted on a finger-ring, 8x and 10x pocket models. Most are only useful for looking at things at long distances, over 10 feet (3m) away, but a few can focus right down to 10 inches (25 cm).
They are useful for looking at distant objects such as bus and train signs, house numbers, signboards in large buildings etc. I always carry a pocket monocular for reading the destination boards on the London Underground. I find a monocular is not good for looking at anything moving (like the signboard on the front of a bus) as the field of view is too small. Monoculars are often sold in camera shops or department stores with photographic departments. |
| Binocular |
A pair of binoculars can be useful, but someone with LHON may only have useful vision in one eye. Most are only useful for looking at things at long distances, over 10 feet (3m) away, but a few can focus right down to 10 inches (25 cm).
They are useful for looking at distant objects such as bus and train signs, house numbers, signboards in large buildings etc. Binoculars are a little easier to find than monoculars, and come in small sizes which are not too inconvenient to carry, but generally the size and cumbersomeness restricts their usefulness as an aid. Binoculars are often sold in camera shops or department stores with photographic departments. |
| Low Power Magnifying Glass |
Although low-power magnifying glasses or lenses are fairly easy to obtain, someone affected by LHON may find them too weak to be of any practical use. I have found that most easily available magnifying glasses magnify up to about 4x, which is not enough to make ordinary print readable for me. Having said this, someone with quite a lot of useable vision may find a magnifying glass useful.
Low-power magnifying glasses are often sold in high-street opticians or department stores with photographic departments. |
| High Power Magnifying Glasses |
High-power magnifying glasses or lenses are harder to obtain, but someone affected by LHON may find them the most practical to use. I have found small folding hand magnifying glasses (hand lenses) at strengths of 8x, 10x, 12x, 15x and 20x. I find that with a 20x hand lens I can make out most small print such as telephone directories and labels on jars or bottles.
Do not assume that the most powerful lens is automatically the best to use. I find with my eyesight that sometimes an 8x is best, sometimes a 15x and sometimes a 20x. Someone else affected by LHON may find that an 8x is quite powerful enough and a 10x is too strong. Using lenses this powerful is difficult and takes practice. The lens magnifies movement as well, so at very high strengths even the movement caused by your pulse in your arm can be a problem. High-power magnifying glasses are sometimes sold in high-street opticians or department stores with photographic departments. They are hard to find, and usually sold by low-vision or scientific specialist outlets. |
| Spectacle-mounted Magnifying Glass |
A magnifying lens mounted in a spectacle frame has the big advantage of leaving both hands free. This is useful when working on something, using a keyboard or holding a book. I have seen 4x, 8x, 10x and 12x spectacle mounted lenses, and personally use an 8x lens most of the time. I find mine invaluable for reading, working and using a computer.
These are much harder to find, as the spectacle frame has to be fitted like any normal pair of spectacles. In the U.K. a specialist Low Vision Aids clinic, either National Health Service or private, is the best place for high-powered magnifiers and other vision aids. I recently got my new spectacle-mounted lenses from Moorfields Eye Hospital in London. |
| Spectacle-mounted Binoculars or electronic magnifiers |
Recently developed, these are either optical or electronic aids
which are worn on the head like a pair of spectacles. The optical
versions (e.g. by BEECHER) are binoculars with 4x or 7x magnification.
The electronic versions (e.g. by OCUTECH) are auto-focus cameras
with high magnification. Some can work close-up as well as at a distance.
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Illuminated or Stand Mounted Magnifying Glass |
Two main problems with magnifying glasses or lenses are lighting and having to hold the lens in one hand. There are several magnifiers on the market with their own built-in light, or mounted on small stands so that you do not have to hold them in your hand. These can be useful at times, for specialist purposes like hobbies when you do not have to carry the aid around with you. Personally I do not find any of them useful and prefer to make sure that the lighting is good enough to use with my spectacle-mounted or pocket lenses.
Low-power magnifying glasses, either illuminated or mounted on a stand, are often sold in high-street opticians or department stores with photographic departments. |
| Computer Screen Readers |
A screen reader is a special computer program which is installed
on your home or work PC. The program reads text on the screen,
usually through the sound output of your computer (the 'sound card').
There are several screen reader programs available, but the most popular ones seem to be JAWS and Window-EYES. The latest versions of screen readers have special functions to read web pages from
the Internet. There are also screen reader programs specially
designed to read web pages, such as IBM Home Page.
Screen reader programs are expensive. If you are thinking of buying a screen reader program you need to check that you have a computer powerful enough to run the program and that your computer, especially its 'sound card' is compatible with the program. Check with your software supplier and try the pgrogram out to make sure that you are comfortable using it before you buy. If you want more information on screen readers I'd recommend posting a message on the LHON mailing list to discuss your needs there. |
| Lighting |
As mentioned above, a problem with using any sort of magnifier can be lighting. Getting the right level of light, i.e. bright but not glaring, is essential to making best use of your eyesight. An adjustable lamp such as the classic 'angle-poise' can be very useful as you can set the bulb just where you want it.
Normal room lights are a lot dimmer than most people realise - many give off a dull yellow light. Try using brighter (higher wattage) bulbs or adding extra lamps in places where you want to read. |
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Closed-Circuit
Television |
A Closed-Circuit TeleVision (CCTV) magnification system is made up of an electronic camera, control unit and a TV screen to show the image.There are several different types of CCTV available. Some of the simplest are just small cameras which can be hand-held and run over a page, connected to your own TV set. Some of the very large and sophisticated ones have cameras mounted over special holders for
the book and their own built-in TV screens. Some of these more sophisticated systems can magnify pretty well anything, not just print.
There are portable versions which are only designed for reading print, where the display is a specialised small screen about the size of a paperback book, rather than a TV. CCTV systems can give huge levels of magnification, and so can enable someone with very little eyesight to read. As you might expect, using this sort of system can be very slow, and the system is not very portable. There are several CCTV systems advertised in the Partially Sighted Society magazine, 'OCULUS'. CCTV systems are, as you would expect, expensive, and not necessary unless you have extremely limited vision. I would certainly recommend trying magnifying lenses before opting for a CCTV system. |
| Liquid Level Indicator |
This is a small, battery-powered probe which hangs over the edge of a cup, mug or bowl. It beeps when the liquid level in the container reaches the probe, so you know when to stop filling. Very useful for making coffee or tea, pouring cold drinks etc.
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| TAXI hailing card |
This is a fluorescent orange/yellow plastic card with the word TAXI printed on it in bold black lettering. It is small enough to fit into a pocket but large enough to be easily visible when held up at a roadside. There is a small notch so even someone with no vision can tell which way up the card is. This is very useful when trying to hail a cab on the busy streets of London!
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| Talking Alarm Clock |
There are many talking clocks and watches now, even on the ordinary commercial market. I find that a sports-style wristwatch with black dial and bright luminous hands is visible enough during the day, but a talking alarm clock is useful to wake me up.
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| Clothes Clips |
These are small, washable, plastic clips. They are brightly coloured and have Braille lettering on them so they are easy to tell apart. There are two main uses for them:
- Keeping pairs of items together (like socks). - Marking two items like shirts of similar colours so I know which is which. |
Moorfields Eye Hospital
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| As well as the main hospital in London offering private aand NHS consultancy, Moorfields has several outreach clinics throughout the U.K. - contact your G.P. for a referral. | |
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Keeler (UK)
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| A manufacturer and supplier of Low Vision Aids. Includes aids for close-up work and distance, and the NuVision spectacle-mounted electro-optical aid for both near and distant viewing. | |
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Magnifico
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| A supplier of low and medium power magnifiers based in Harrow, UK. Has on on-line shop with a wide range on offer. | |
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Optima
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| A supplier of low vision aids based in Totnes, Devon, UK. Has on on-line shop with a wide range on offer. The sole UK distributor for some brands. | |
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Force 10
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| A supplier of electronic low vision aids, CCTVs and software based in Surrey, UK. Has on on-line shop with a wide range on offer. | |
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COBOLT SYSTEMS
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| A mail-order low vision aids company based in Norfolk, U.K. which sells clocks, watches, cooking and household aids etc. | |
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RNIB on-line catalogue
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| The Royal National Institute for the Blind has a Resource Centre in the entranceway of its head office at 105 Judd Street, London WC1H 9NE where you can see and try many products. It also has a mail order and on-line ordering service. | |
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Freedom Scientific / Hunter-Joyce
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| Freedom Scientific - supplier of JAWS for Windows screen reader software. A free time-restricted demonstration version is available for download. | |
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Sight and Sound
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| UK company dealing in screen magnification and screen reading software as well as CCTV magnifiers. | |
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LS&S Group
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| US based supplier of a variety of aids. Catalogue available for download. | |
| US National Association for Visually Handicapped has an on-line store for low vision aids. | |
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MAXI-AIDS
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| New York based company with on-line catalogue of aids for the disabled including low-vision aids. | |
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Learn More aids for children
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| A division of Maxi-Aids specialising in aids for children. | |
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Guide Dogs for the Blind Assocation
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| A guide dog can be a huge aid to confidence and independence as well mobility. | |
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Talking Newspaper Association, U.K.
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| Although a lot of national news and information can be found on talk radio such as BBC Radio 4, a Talking Newspaper can provide information with more local interest. | |
| A collection of links relating to low vision aids. | |