What is Age Related Macular Degeneration?
Age related macular degeneration (AMD) is the leading cause of blindness in Australia. AMD occurs as a result of the age-related changes in the function of the macula. The macula is a very small part of the retina, the light sensitive tissue at the back of the eye, which is responsible for central vision.
How does it affect your vision?
The visual changes you may notice as AMD progresses are:
- Difficulty reading small print or street signs while wearing spectacles
- Difficulty recognising faces and identifying small objects while wearing spectacles
- Twisting and distortion of straight lines eg. Door frames and windows
- Gradual changes in colour vision – colours look faded
- A centrally located dark or empty blob in the field of vision
Side vision is NOT affected.
What are the risk factor for AMD?
The most important controllable risk factor for AMD is smoking. People who smoke are about 2.5 times more likely to develop AMD than those who have never smoked. You should be screened for the signs and symptoms of AMD if you:
- Smoke or have done in the past
- Are older than 50 years
- Have hypertension or cardiovascular disease
- Have a family history of AMD
- Have a history of significant light exposure, eg. Working outdoors
- Have any of the symptoms of AMD mentioned above
How is AMD Detected and diagnosed?
Many people do not realise they have a problem until their vision becomes significantly blurred. Our optometrists perform a number of tests in the examination, which enables them to detect the presence of AMD in the early stages.
Our optometrists examine the macula carefully with a range of specialised instruments such as an ophthalmoscope, retinal camera or slitlamp with a high powered lens. These instruments allow a highly detailed 3D examination of the interior of the eye, including the macula. Our optometrists routinely also place an eye drop in the eye to dilate the pupil to get a better view of the internal structures. With these specialised instruments the optometrist will look for changes in the macula, such as accumulation of waste material or new blood vessels.
Another test that may be used is a grid pattern known as an Amsler grid. Patients with AMD often report that sections of the grid appear to be distorted or missing.
What should you do about AMD?
Early diagnosis of AMD is necessary for possible treatments to be effective. Regular eye examinations are the key to early detection of retinal changes and other signs of disease. If you notice any change in the quality of your vision, have your eyes examined immediately. Regular examinations are particularly important for people over the age of 50 years and people who have a family history of eye problems.
Other preventative measures include minimising exposure to UV light and cigarette smoke. A low fat diet (reducing saturated fats), rich in green leafy vegetables, nuts and fish may be beneficial in reducing the impact of AMD. Supplements such as Omega 3/Fish Oil, B group vitamins and folic acid may be beneficial in reducing the impact of AMD. Patients should speak to their Family Doctor before taking any supplements.