Cleon Hutton and Amanda Reeves of Macular Society, explain the importance of eccentric viewing and steady eye techniques for service users with central vision loss.
There are around 600,000 people believed to be living with late stage age-related macular degeneration (AMD) in the UK. With more than 80,000 new cases of AMD expected each year, a significant number of service users will face the news that they are developing signs of macular disease or will already be living with central vision loss.
The loss of fine detail and reduced colour vision makes everyday activities such as reading and telling the time, shaving and nail cutting very difficult.
In patients with central vision loss in both eyes, eccentric viewing (EV) training may be a viable tool to help people use what remains of their vision.
EV involves identifying an area of the retina that retains reasonable functionality, and is as close to the fovea - the most central part of the macula and responsible for our central, sharpest vision - in order to maximise detail, and learning to use it effectively.
Some people with central vision loss use EV for distance tasks - many find they can see a friend's face or the television better when they are not looking directly at it. However, not many people adapt this to near tasks without training.
Not everyone with central vision loss will need to use an off centre, better functioning part of their vision in order to see things centrally and in more detail. It will depend on the extent and location of damage to the macula.
Steady Eye Strategy (SES) is a technique specifically for reading. SES requires the person to keep their gaze still, and scroll text right to left, through their best functioning piece of vision. This technique improves accuracy and reading speed, although not to pre-macular disease levels.
A number of tools and techniques can be used to help identify the better functioning piece of vision and to support eccentric fixation, that is to use this better often off centre piece of vision to see things centrally and in more detail.
Work by Cardiff University for the Macular Society found 34 studies had been published about EV and SE training. Almost all the studies found that reading ability improved after training, and there was some evidence that the ability to perform daily tasks, such as cooking and shopping, improved after training. However, more high quality, carefully designed research is needed. More researchers and clinicians should study the impact of eccentric viewing techniques.
Ask the person to look at your face and tell you if there is an area which is clearer or more distinct. If the clearest area is anything other than your nose; ask the person to try and see your nose by pulling their better area of vision into the centre, for example, if the clearest area of your face is your hairline, encourage the person to look towards your chin in order to see your nose.
Ask the person if they can see the centre of the clock. If they can't, ask them if there are any numbers on the clock that are clearer. If for example a person says the number seven is clearest, get them to look towards the number two to see the centre of the dial.
Using an Amsler grid with diagonal lines and a dot in the centre, ask the person to concentrate on the centre of the grid and describe the clearest areas on the chart. Encourage them to use their clearest area of vision to see the centre.
Macular Society operates a Skills for Seeing programme which provides free one to one coaching in EV and SES for people with central vision loss. Call the helpline on 0300 3030 111 for further information.
Eye health and sight loss professionals can sign up for professional membership with the Macular Society to keep up to date with the latest developments in EV with Macular Society.