AMD - Macular Degeneration


Symptoms of macular degeneration

Causes of macular degeneration

Diagnosing macular degeneration

Treating macular degeneration

Complications of macular degeneration

Case Study 'Giving up driving was hard. A part of my independence had gone'


Age-related macular degeneration (AMD) is a painless eye condition that causes you to lose central vision, usually in both eyes.

Central vision is what you see when you focus straight ahead. In AMD, this vision becomes increasingly blurred, which means:

  • reading becomes difficult 
  • colours appear less vibrant
  • people's faces are difficult to recognise

This sight loss usually happens gradually over time, although it can sometimes be rapid.

AMD doesn't affect your peripheral vision (side vision), which means it will not cause complete blindness.  

Read more about the symptoms of age-related macular degeneration and the complications of age-related macular degeneration.

When to seek medical advice

Visit your GP or optometrist if your vision is getting gradually worse. If your vision suddenly gets worse, images are distorted or you notice blind spots in your field of vision, seek medical advice immediately and book an emergency appointment with an optometrist.

If AMD is suspected, you'll be referred to an ophthalmologist (eye specialist) for tests and any necessary treatment.

Read more about how age-related macular degeneration is diagnosed.

Why it happens

Macular degeneration develops when the part of the eye responsible for central vision (the macula) is unable to function as effectively as it used to. There are two main types – dry AMD and wet AMD.

Dry AMD

Dry AMD develops when the cells of the macula become damaged by a build-up of deposits called drusen. It's the most common and least serious type of AMD, accounting for around 9 out of 10 cases.

Vision loss is gradual, occurring over many years. However, an estimated 1 in 10 people with dry AMD go on to develop wet AMD.

Wet AMD

Wet AMD – sometimes called neovascular AMD – develops when abnormal blood vessels form underneath the macula and damage its cells.

Wet AMD is more serious than dry AMD. Without treatment, vision can deteriorate within days.

Read more about the causes of age-related macular degeneration.

Who's affected?

AMD currently affects more than 600,000 people in the UK and is the leading cause of vision loss. By 2020, it's predicted almost 700,000 people will have late-stage AMD in the UK. 

For reasons that are unclear, AMD tends to be more common in women than men. It's also more common in white and Chinese people.

The condition is most common in people over the age of 50. It's estimated 1 in every 10 people over 65 have some degree of AMD.

Treating macular degeneration

There's currently no cure for either type of AMD. With dry AMD, treatment aims to help a person make the most of their remaining vision – for example, magnifying lenses can be used to make reading easier.

There's some evidence to suggest a diet rich in leafy green vegetables may slow the progression of dry AMD.

Wet AMD can be treated with anti-vascular endothelial growth factor (anti-VEGF) medication. This aims to stop your vision getting worse by preventing further blood vessels developing.

In some cases, laser surgery can also be used to destroy abnormal blood vessels.

The early diagnosis and treatment of wet AMD is essential for reducing the risk of severe vision loss.

Read more about treating age-related macular degeneration.

Reducing your risk

It's not always possible to prevent macular degeneration because it's not clear exactly what triggers the processes that cause the condition.

Your risk of developing AMD is closely linked to your age and whether you have a family history of the condition.

However, you may be able to reduce your risk of developing AMD, or help prevent it getting worse, by:

Macula
The macula is a small spot at the centre of the retina. It is the part of your eye where incoming rays of light are focused.
Retina
The retina is the nerve tissue lining the back of the eye. It senses light and colour and sends it to the brain as electrical impulses.
Visual impairment
The term visual impairment refers to anyone who is blind or partially sighted, rather than those who are short-sighted (myopia), or long-sighted (hyperopia).

Symptoms

Age-related macular degeneration (AMD) isn't a painful condition. Some people don't realise they have it until they notice a loss of vision.

The main symptom of macular degeneration is blurring of your central vision (what you see when you focus straight ahead). This means:

  • you lose visual acuity – the ability to see fine detail, so reading and driving become difficult  
  • you lose contrast sensitivity – the ability to distinguish between objects such as faces against a background 
  • images, writing or faces can become distorted in the centre – most commonly associated with wet AMD

Your peripheral vision (side vision) isn't affected. Glasses won't be able to correct your blurred central vision.

Both eyes tend to eventually be affected by AMD, although you may only notice problems in one eye to begin with.

Dry AMD

If you have dry AMD, it may take 5 to 10 years before your loss of vision significantly affects your daily life.

Sometimes your healthy eye will compensate for any blurring or vision loss if only one of your eyes is affected. This means it will take longer before your symptoms become noticeable.

You may have dry AMD if:

  • you need brighter light than normal when reading
  • text appears blurry
  • colours appear less vibrant
  • you have difficulty recognising people's faces
  • your vision seems hazy or less well defined

If you're experiencing any of these symptoms, you should make an appointment with your GP or local optometrist (a healthcare professional trained to recognise signs of eye problems).

Read about diagnosing age-related macular degeneration.

Wet AMD

In most cases, wet AMD develops in people who've already had dry AMD.

If you have wet AMD, any blurring in your central vision will suddenly worsen.

You may also experience other symptoms, such as:

  • visual distortions – for example, straight lines may appear wavy or crooked
  • blind spots – these usually appear in the middle of your visual field and become larger the longer they're left untreated
  • hallucinations – seeing shapes, people or animals that aren't really there

See complications of AMD for more information.

Book an emergency appointment with an optometrist if you experience sudden changes in your vision, such as those described above.

Wet AMD needs to be treated as soon as possible to stop your vision getting worse.


Causes

The exact cause of macular degeneration isn't known, but the condition develops as the eye ages.

Age-related macular degeneration (AMD) is caused by a problem with part of the eye called the macula. The macula is the spot at the centre of your retina (the nerve tissue that lines the back of your eye).

The macula is where incoming rays of light are focused. It helps you see things directly in front of you and is used for close, detailed activities, such as reading and writing. 

Dry AMD

As you get older, the light-sensitive cells in the macula can start to break down. This tends to occur gradually, often over many years.

Waste products can also begin to build up in your retina, forming small deposits called drusen. Drusen are a common feature of dry AMD and tend to increase in size as the condition progresses.

As dry AMD progresses, you'll have fewer light-sensitive cells in your macula, causing your central vision to deteriorate. A blurred spot will develop in the centre of your vision, making your central vision less well-defined. As a result, you may need more light when reading and carrying out other close work.

Wet AMD

In cases of wet AMD, tiny new blood vessels begin to grow underneath the macula. It's thought these blood vessels form as an attempt by the body to clear away the drusen from the retina.

Unfortunately, the blood vessels form in the wrong place and cause more harm than good. They can leak blood and fluid into the eye, which can cause scarring and damage to your macula.

The damage and scarring causes the more serious symptoms of wet AMD to develop, such as distorted vision and blind spots.

Increased risk

It's unclear what triggers the processes that lead to AMD, but a number of things increase your risk of developing it. These are described below.

Age

The older a person gets, the more likely they are to develop at least some degree of AMD.

Most cases start developing in people aged 50 or over and rise sharply with age. It's estimated 1 in every 10 people over 65 has some signs of AMD.

Family history

AMD has been known to run in families. If your parents, brothers or sisters develop AMD, it's thought your risk of also developing the condition is increased.

This suggests certain genes you inherit from your parents may increase your risk of getting AMD. However, it's not clear which genes are involved and how they're passed through families.

Smoking

A person who smokes is up to four times more likely to develop AMD than someone who's never smoked.

The longer you've been smoking, the greater your risk of getting AMD. You're at even greater risk if you smoke and have a family history of AMD.

Read more about how to stop smoking.

Ethnicity

Studies have found rates of AMD are highest in white and Chinese people, and lower in black people. This could be the result of genetics.

Other possible risk factors

The following things may increase your risk of developing AMD, although this hasn't yet been proven.

Alcohol

It's possible drinking more than four units of alcohol a day over many years may increase your risk of developing early AMD.

Sunlight

If you're exposed to lots of sunlight during your lifetime, your risk of developing macular degeneration may be increased. To protect yourself, you should wear UV-absorbing sunglasses if you spend long periods of time outside in bright sunlight.

Obesity

Some studies have reported being obese – having a body mass index (BMI) of 30 or greater – may increase your chance of developing AMD.

High blood pressure and heart disease

There's some limited evidence that having a history of high blood pressure (hypertension) or coronary heart disease may increase your risk of developing AMD.

Macula
The macula is a small spot at the centre of the retina. It is the part of your eye where incoming rays of light are focused.
Retina
The retina is the nerve tissue lining the back of the eye. It senses light and colour and sends it to the brain as electrical impulses.

Diagnosis

In some cases, early age-related macular degeneration (AMD) may be detected during a routine eye test before it starts to cause symptoms.

If you're experiencing symptoms of macular degeneration, such as blurred central vision, visit your GP or make an appointment with an optometrist, a healthcare professional trained to recognise signs of eye problems.

Find your nearest optician.

Referral

If your GP or optometrist thinks that you have wet AMD, you'll be referred to an ophthalmologist (a doctor who specialises in diagnosing and treating eye conditions).

Your appointment will usually be at a hospital eye department. If you need to travel by car to the hospital, ask someone else to drive you back as the eye drops given to you may make your vision blurry.

Eye examination

The ophthalmologist will examine your eyes. You'll be given eye drops to enlarge your pupils. These take around half an hour to start working, and may make your vision blurry or your eyes sensitive to light. The effect of the eye drops will wear off after a few hours.

The ophthalmologist will use a magnifying device with a light attached to look at the back of your eyes, where your retina and macula are. They'll check for any abnormalities around your retina.

The ophthalmologist will then carry out a series of tests to confirm a diagnosis of macular degeneration.

Amsler grid

One of the first tests involves asking you to look at a special grid, known as an Amsler grid. The grid is made up of vertical and horizontal lines, with a dot in the middle.

If you have macular degeneration, it's likely some of the lines will appear faded, broken or distorted. Saying which lines are distorted or broken will give your ophthalmologist a better idea of the extent of the damage to your macula.

As the macula controls your central field of vision, it's usually the lines nearest to the centre of the grid that appear distorted.

Eyecare Trust has a version of the Amsler grid (PDF, 51.2kb) on its website that you can print off and use at home to check for possible signs of AMD.

Retinal imaging

As part of your diagnosis, your ophthalmologist will need to photograph your retinas to see what damage, if any, macular degeneration has caused.

As well as confirming the diagnosis, the images will prove useful in planning your treatment. There are several different ways of taking pictures of the retina.

Fundus photography

A fundus camera is a special camera used to take photographs of the inside of your eye. It can capture three-dimensional images of your macula. Your ophthalmologist can then look at the different layers of your retina to see what damage, if any, has occurred. 

Fluorescein angiography

Angiography is an examination that creates detailed images of your blood vessels and the bloodflow inside them. A special dye is injected into your blood vessels and pictures are taken that show any abnormalities inside them.

The procedure can confirm which type of AMD you have. It may be carried out if your ophthalmologist suspects wet AMD.

Your ophthalmologist will inject a special dye called fluorescein into a vein in your arm. The dye will move through your blood vessels into your retina. They will look into your eyes using a magnifying device and take a series of pictures using a special camera.

These images will allow your ophthalmologist to see whether any of the dye is leaking from the blood vessels behind your macula. If it is, this may confirm you have wet AMD.

Indocyanine green (ICG) angiography

The technique used for indocyanine green (ICG) angiography is the same as for fluorescein angiography, but the dye is different. ICG dye can highlight slightly different problems in your eyes.

Optical coherence tomography (OCT)

Optical coherence tomography (OCT) uses special rays of light to scan your retina and produce an image of it. This can provide detailed information about your macula. For example, it will tell your ophthalmologist whether your macula is thickened or abnormal, and whether any fluid has leaked into the retina.

Staging of AMD

Once these tests have been completed, your ophthalmologist should be able to tell you how far your AMD has progressed.

Dry AMD has three main stages, described below.

  • early – at this stage there may be many small collections of drusen (deposits) inside the eye, a few medium-sized drusen, or some minor damage to your retina; early AMD may not cause any noticeable symptoms
  • intermediate – there may be some larger drusen inside the eye or some tissue damage to the outer section of the macula; you'll have a blurred spot in the centre of your vision
  • advanced – the centre of the macula is damaged; you'll have a large blurred central spot and find it difficult to read and recognise faces

Wet AMD is always considered to be an advanced form of AMD.

Macula
The macula is a small spot at the centre of the retina. It is the part of your eye where incoming rays of light are focused.
Retina
The retina is the nerve tissue lining the back of the eye. It senses light and colour and sends it to the brain as electrical impulses.
X-ray
An X-ray is an imaging technique that uses high-energy radiation to show up abnormalities in bones and certain body tissue, such as breast tissue.

Complications

Being told you have age-related macular degeneration (AMD) can be frustrating and upsetting, as simple everyday tasks such as reading become more difficult.

Speak to your GP if macular degeneration is having a significant effect on your daily life. They should be able to put you in touch with local support groups, who can provide guidance and practical help.

Alternatively, you could call the Macular Society helpline on 0300 3030 111 (open Monday to Friday, 9am to 5pm) or the Royal National Institute of Blind People helpline on 0303 123 9999 (open Monday to Friday, 8.45am to 5.30pm).

Read more about help and support for blindness and vision loss.

Depression and anxiety

Having to cope with losing part of your vision and coming to terms with the loss of some of your independence can be difficult, and it can affect your mental health.

It's estimated around a third of people with AMD may have some form of depression or anxiety.

If you're struggling with the changes to your life, you should speak to your GP or ophthalmologist (eye specialist). They'll be able to discuss treatment options with you, such as counselling, or they can refer you to a mental health professional for further assessment.

Driving

You'll need to inform the DVLA and your insurance company if you're diagnosed with AMD and you drive, as the condition may affect your ability to drive.

If your eyesight is only slightly affected, it may still be safe for you to drive a vehicle. However, you'll probably need to have a series of sight tests to prove this. Central vision is very important for driving, and you won't be able to drive if you don't meet the standards set by the DVLA.

The GOV.UK website has more information and advice about macular degeneration and driving.

Visual hallucinations

Some people with macular degeneration experience visual hallucinations caused by their low vision. This is known as Charles Bonnet syndrome. It's estimated about 1 in 10 people with AMD experiences Charles Bonnet syndrome.

As AMD can prevent you from receiving the visual stimulation you're used to, your brain can sometimes compensate by creating fantasy images or using images stored in your memory. These are known as hallucinations.

The hallucinations you experience may include unusual patterns or shapes, animals, faces, or an entire scene. They can be either black and white or colour, and may last from a few minutes to several hours. They're usually pleasant images, although they may be unsettling and scary to experience.

Many people with Charles Bonnet syndrome don't tell their GP about their symptoms because they worry it may be a sign of a mental condition. However, the hallucinations experienced with this syndrome are usually the result of a problem with your vision and not a reflection of your mental state.

Speak to your GP if you experience any kind of visual hallucination. There are ways they can help you learn how to cope. The hallucinations will usually last for around 18 months, although they may last years for some people. 

Treatment

There's currently no cure for either type of age-related macular degeneration (AMD), although vision aids and treatments may help.

Dry AMD

With dry AMD, the deterioration of vision can be very slow. You won't go completely blind, as your peripheral (side) vision shouldn't be affected.

Help is available to make tasks such as reading and writing easier. Getting practical help may improve your quality of life and make it easier for you to carry out your daily activities.

You may be referred to a low vision clinic. Staff at the clinic can provide useful advice and practical support to help minimise the effect dry AMD has on your life. For example, you may wish to try:

  • magnifying lenses
  • large-print books
  • very bright reading lights
  • screen-reading software on your computer so you can "read" emails and documents, and browse the internet

Read more about changes to your home to make it easier to live with low vision.

Diet and nutrition

There's some evidence a diet high in vitamins A (beta-carotene), C and E – as well as substances called lutein and zeaxanthin – may slow the progression of dry AMD, and possibly even reduce your risk of getting wet AMD. Talk to an ophthalmologist about whether these could help you.

Foods high in vitamins A, C and E include:

  • oranges
  • kiwis
  • leafy green vegetables
  • tomatoes
  • carrots

Leafy green vegetables are also a good source of lutein, as are peas, mangoes and sweetcorn.

There's no definitive proof eating these foods will be effective for everyone with dry AMD, but this type of healthy diet has other important health benefits, too.

Dietary supplements are also available, some of which claim to specifically improve eye health. However, these are rarely prescribed on the NHS so you'll usually have to buy them. It's important to check with your GP before taking supplements as they may not be suitable for everyone.

Read more about vitamins and minerals.

For more information, read a factsheet produced by the Macular Society about nutrition and eye health.

Wet AMD

The two main treatment options for wet AMD are:

  • anti-VEGF medication – to prevent the growth of new blood vessels in the eye
  • laser surgery – to destroy abnormal blood vessels in the eye

These treatments are described below.

Anti-VEGF medication

VEGF stands for vascular endothelial growth factor. It's one of the chemicals responsible for the growth of new blood vessels in the eye caused by wet AMD. Anti-VEGF medicines block this chemical, stopping it producing blood vessels and preventing wet AMD getting worse.

The medication is injected into your eye using a very fine needle. You'll be given local anaesthetic eye drops so the procedure doesn't hurt. Most people tolerate this very well, with minimal discomfort.

In some cases, anti-VEGF medication can shrink the blood vessels in the eye and restore some of the sight lost as a result of macular degeneration. But your sight won't be restored completely, and not everyone will see an improvement.

The anti-VEGF medications currently available on the NHS are ranibizumab and aflibercept, but these will only be prescribed if there's clear evidence using the medication will help improve or maintain your eyesight.

Current recommendations are that ranibizumab and aflibercept should only be used if:

  • your visual acuity (ability to detect fine detail) is between 6/12 and 6/96
  • there's no permanent damage to the fovea, the part of the eye that helps you see things in sharp detail
  • the area affected by AMD is no larger than 12 times the size of the area inside the eye where the optic nerve connects to the retina
  • there are signs the condition has been getting worse

Your ophthalmologist should be able to tell you if you're suitable for treatment with ranibizumab or aflibercept.

Ranibizumab (Lucentis)

Studies show ranibizumab (brand name Lucentis) can help slow loss of visual acuity in more than 90% of people, and may even increase visual acuity in around a third of people.

The injection into the eye will be given be a specialist doctor who's trained to administer these type of injections.

To start with, you'll have a monthly injection of ranibizumab for three consecutive months. Your visual acuity will then be monitored during a maintenance phase.

If your vision deteriorates during the maintenance phase, and it's thought to be caused by further fluid leakage, you may be given another injection of ranibizumab. Monitoring will continue and you'll have injections as necessary, with at least one month between injections.

Treatment with ranibizumab will be stopped if your condition doesn't show signs of improvement or continues to get worse.

Common side effects of ranibizumab include:

  • minor bleeding in the eye
  • feeling like there's something in the eye
  • inflammation or irritation of the eye
  • increased pressure within the eye

Aflibercept (Eylea)

Aflibercept (brand name Eylea) is a newer type of anti-VEGF medication for wet AMD. Studies have shown it's at least as effective as ranibizumab in treating people with the condition.

As with ranibizumab, a specialist doctor who's experienced in giving this type of eye injection will administer aflibercept.

To start with, you'll have a monthly injection of aflibercept for three consecutive months. There's no need for monitoring between injections. Depending on the outcome of treatment, you may have further injections once every two months.

After 12 months, the intervals between injections may be extended depending on how well the medication is working. In this case, the doctor treating you will determine a monitoring schedule.

Common side effects of aflibercept are similar to those of ranibizumab and may include minor bleeding, eye pain, eye irritation and increased eye pressure.

Surgery

Photodynamic therapy

Photodynamic therapy (PDT) was developed in the 1990s. It involves having a light-sensitive medicine called verteporfin injected into a vein in your arm.

The verteporfin attaches itself to the abnormal blood vessels in your macula. A low-powered laser is then shone into your damaged eye over a circular area just larger than the affected area in your eye. This usually takes around one minute.

The light from the laser is absorbed by the verteporfin and activates the drug. The activated verteporfin destroys the abnormal vessels in your macula while reducing harm to other delicate tissues in your eye.

Destroying the blood vessels stops them leaking blood or fluid, preventing damage and therefore stopping the macular degeneration getting worse. You may need this treatment every few months to ensure any new blood vessels that start growing are kept under control.

PDT isn't suitable for everyone – it will depend on where the blood vessels are growing and how severely they've affected your macula. It may be suitable if your visual acuity is 6/60 or better. This means you can see from a distance of six metres what someone with normal vision can see from a distance of 60 metres.

Laser photocoagulation

Laser photocoagulation can also be used to treat some cases of wet AMD. This type of surgery is only suitable if the abnormal blood vessels aren't close to the fovea, as performing surgery close to this part of the eye can cause permanent vision loss.

Around one in seven people may be suitable for treatment with laser photocoagulation. A powerful laser is used to burn sections of the retina. These sections harden, which prevents the blood vessels moving up into the macula.

The surgery is carried out under local anaesthetic to numb the eye, so it isn't painful. One side effect of laser photocoagulation is a permanent black or grey patch developing in your field of vision. This loss of vision is usually – but not always – less severe than untreated wet AMD.

If you're considering laser photocoagulation, you should discuss the pros and cons of the treatment with the doctor in charge of your care. The results tend to be less effective than the other treatments discussed above, so it only tends to be used in people who cannot be treated with anti-VEGF medication or PDT.

Radiotherapy

Radiotherapy has been used to treat wet AMD in the past with varying results. Research was carried out recently to see whether using radiotherapy in combination with anti-VEGF injections may be of benefit in reducing the number of injections needed. The early results of some studies are encouraging, but the long-term benefits are still unknown.

Radiotherapy may be available as part of a clinical trial. You'll need to be advised by your ophthalmologist as to whether you may be suitable for the treatment.

Newer types of surgery

In recent years, two new surgical techniques have been developed to treat wet AMD. These are:

  • macular translocation – where the macula is repositioned over a healthier section of the eyeball not affected by abnormal blood vessels
  • lens implantation – where the lens of the eye is removed and replaced with an artificial lens designed to enhance central vision

Both approaches tend to achieve better results than laser surgery, but there are also disadvantages, such as:

  • limited access to these treatments – they may only be available in the context of a clinical trial
  • uncertainty about whether these treatments are safe and effective in the long term
  • they carry a higher risk of serious complications than laser surgery

The National Institute for Health and Care Excellence (NICE) has more information about macular translocation (PDF, 97kb) and lens implantation (PDF, 100kb) on its website.

Case Study - 'Giving up driving was hard. A part of my independence had gone'

Barbara Watson talks about how age-related macular degeneration (AMD) affected her.

"I found out I had macular degeneration when I went to the optician for some new glasses. The optician examined my eyes and bluntly told me: 'You've got macular degeneration, but don't worry, you won't go completely blind.' 

"It was a horrible surprise. My mother had macular degeneration, but it hadn't occurred to me that I might also have it one day. The signs had probably been there, but I hadn't noticed them. I'd been doing a lot of numerical work and was having problems reading the numbers 6, 8 and 3. I had to concentrate very hard not to get them muddled up.

"At first it wasn't too much of a problem. My right eye was affected, and it stayed that way for three years. But when I began to get macular degeneration in my left eye, I had to give up driving. That was hard because a part of my independence had gone. Luckily my husband drives, so I can still get around, but it was a difficult time.

"In the last few years, the condition has progressed more rapidly. I've had to give up a number of things I really liked doing, such as calligraphy and tapestry. Reading has become difficult, so I now listen to talking books. I've also been in some embarrassing situations where I've passed friends in the street and not recognised them. 

"I always tried to hide it from people, but lately I've started using a white stick when I'm somewhere that's busy or unfamiliar. At first I wasn't keen on using a stick, but once I got over the embarrassment I've found that it's helpful because people do get out of your way.   

"I'm still a steward at the local museum, and I've also joined a walkers group, which is great fun. When I joined the Macular Society it opened up lots of new doors and I've done a lot of fundraising. I've written about my feelings in two books of poems, which have both been published. That's been lovely. And I help my husband with the gardening when I can, although last week I dug up the sage instead of the mint – so it can be a bit hazardous sometimes!"


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