The macula is the central part of the retina that is designed to give us both high visual acuity and colour vision. The very centre of the macula is called the fovea. The normal macula is rich in yellow pigments (lutein; zeaxanthin; and meso-zeaxanthin) that act as a protective shield against potentially damaging blue and ultra violet light.
Age-related Macular Degeneration (AMD) is the leading cause of vision loss in people over fifty. There are four main risk factors for AMD
- The risk and prevalence of AMD increases with age
- Having a close member of the family who has the disease increases your risk
- Smoking significantly increases risk
- Reduced pigment at the macula is a strong risk factor
People with macular degeneration experience severely distorted vision and loss of colours that makes it very difficult to read and recognise faces. Considering that one third of all you perceive comes via your eyes, this would make a huge difference to your quality of life.Unfortunately, by the time the symptoms of AMD are obvious, it can be too late to do anything about it.
Wet and dry. What's the difference?
"Dry" macular changes occur due to a build up of metabolic debris at the macula and whilst this may not cause problems in the early stages it can progress to a more marked "geographic" atrophy which is just as damaging to sight as "wet" AMD. "Wet" AMD occurs due to new blood vessels being formed which then leak often causing a sudden distortion of vision.
How do you check if you have AMD?
There are a number of tests that your optometrist can use to examine your retina generally and macula in particular. In addition to viewing the macula with a slit lamp microscope and taking an image with Optomap, the Zeiss Cirrus OCT is used to provide a very definitive assessment of the macula.
To look at your risk of developing AMD your optometrist can ask you to perform a simple test that takes just a few minutes and doesn’t hurt. It involves you looking into a special device called a Macular Pigment Screener, the MPS II, one eye at a time. This is a very advanced device that can measure the density of your macular pigment accurately and quickly. At the end of the test you will be given a rating and you’ll be advised whether it is normal or not. If your rating is lower than it should be you can take supplements and make adjustments to your diet and lifestyle to boost the density of your pigment to the desired level. To see if this course of action is working, you simply go and have another screening. We may recommend you do this every six or twelve months. If your macular pigment density is poor, we will discuss your diet with you and advise you on taking nutrition supplements that contain lutein, zeaxanthin and meso-zeaxanthin.
Reducing the risk of AMD
There’s a lot you can do to keep your macular pigment healthy. The components of the pigment are lutein, zeaxanthin and meso-zeaxanthin and these are available in specialised supplements which you can take daily.
- You can alter your diet to increase the mount of fresh fruit and vegetables, especially broccoli and spinach.
- You can stop smoking. Not only does it damage your health generally but it causes visual problems in later life.
- Cutting down on alcohol consumption would help because alcohol is thought to deplete vital antioxidants.
- Wearing UV-blocking sunglasses is advisable.
- Finally, you can avoid excessive exposure to screens which emit blue light, such as the ones with computers and gaming machines
AMD is related to age but you don’t have to be old to have it. AMD used to be regarded as an older person’s disease but changes to our diet and our increasing dependence on screens means that it is increasingly being diagnosed in younger adults. This is why it makes sense for screening to begin as early as possible.
I already have AMD. How can you help me?
Dry AMD is a progressive disorder and the leading cause of visual impairment and blindness in the developed world. Barnard and Levit Optometrists now offer treatment for dry AMD - Valeda, which utilises Photobiomudulation (PBM) to apply specific wavelengths of light to the macula. This is the first evidence based treatment for Dry AMD, Clinical studies have shown that Valeda may improve vision and slow down the progression of macular degeneration. Valeda is the first device designed specifically for Dry AMD treatment.
The Low Vision Clinic at Barnard Levit Optometrists offers a comprehensive private low vision service with the latest Low Vision aids ranging from simple hand held magnifiers to advanced digital magnifiers and telescopes. We also offer a unique Reading Rehabilitation training program that can train someone who has given up reading, how to read again using their remaining peripheral vision.
If you suffer from advanced 'End-Stage' AMD you may be a candidate for a new revolutionary treatment where an Implantable Miniature Telescope about the size of a pea is implanted into the eye to enable one to have usable central vision again. To read more about this exciting development and to find out if you are a candidate please click here - The CentraSight Implantable Telescope Treatment Programme