Age-related macular degeneration (AMD): Symptoms, diagnosis, treatment and prevention
Age-related macular degeneration (AMD) affects a person's central eyesight and is the leading cause of vision loss in the UK.
In AMD the central part of the retina, called the macula, deteriorates. The macula is the part of the retina responsible for focused, precise vision, such as reading, looking at faces and seeing colours.
It is central vision that is affected, but not peripheral vision. Glasses or contact lenses cannot correct this central vision loss.
AMD usually happens gradually over time, but deterioration of vision can occur more quickly.
There are two forms of AMD - called dry and wet.
The dry form is the most common where deposits -called drusen - form gradually under the macula.
Around 1 in 10 people with this type of AMD will go on to develop wet AMD.
The 3 stages of dry AMD are:
Early. Small or medium amounts of deposits of drusen, minor retinal damage, symptoms may not be noticed at this stage.
Intermediate. Larger drusen in the eye, tissue damage to the outer macula, blurred central vision.
Advanced. Damaged central macula, considerable central vision blurring.
Wet AMD (neovascular AMD)
This is the more serious form of AMD and damage to the macula comes from abnormal blood vessels forming underneath it.
Wet AMD can cause central vision loss over a matter of days in some cases.
What causes macular degeneration?
The reason some people develop AMD isn't fully understood, but risk factors include:
- Being over 50
- Inherited tendency, AMD is more likely if close relatives had it
- Ethnic background, it’s more common in Caucasian and Chinese people.
Other causes may include:
What are the symptoms of macular degeneration?
Blurred central vision is the main symptom of age-related macular degeneration. However, this often happens slowly over time and one eye may compensate for the other until both eyes are affected.
Lost visual acuity in central vision from AMD can cause:
- Loss of fine detail when reading print
- Difficulty when driving
- Faces appearing distorted
Specific symptoms for dry AMD include:
- More light needed for reading
- Blurry text when reading
- Hazy vision
- Washed out colours
- Finding it hard to recognise faces
Specific symptoms for wet AMD include:
- Distorted central vision with straight lines looking wavy
- Blind spots in central vision
- Seeing things that are not actually there (hallucinations)
Any problems with vision should be checked by an optometrist or ophthalmologist as soon as possible.
How is age-related macular degeneration diagnosed?
Age-related macular degeneration will be diagnosed with a series of eye tests - either through routine check-ups, or after an appointment arranged to investigate vision problems. Tests and procedures include:
Eye drops. These will be given to enlarge the pupils. These can take some time to take effect, and also mean it won’t be possible to drive home from the appointment. Sunglasses may also be needed as the eyes will be more sensitive to light.