ARMD is an aging change or wearing out of the central retina. It causes loss of central vision. This makes reading and driving difficult. Later, if it gets more severe, it becomes difficult seeing faces, crossing roads, and cooking. The peripheral or side vision always remains, so even if the central vision is poor, it is always possible to see and get round the house and see to the side.
ARMD is usually a progressive condition. Invisible early changes occur, then usually some type of dry ARMD, such as drusen. Later, the dry changes may progress, usually slowly, to cause geographic atrophy and thinning of central retina. These are all termed part of 'dry' ARMD. Treatment for geographic atrophy is awaited.
A secondary change may then develop in some people, as the body tries to 'heal' the changes. Blood vessels may start to grow in the centre of the retina in the macula area. The blood vessel growth causes leakage and scarring, and is termed 'wet' ARMD. These wet changes can be slowed down with anti-VEGF eye injections (wet ARMD page).
This page summarises our current knowledge. Age-related macular degeneration is explained in more detail on other
web-sites, such as the RNIB and NIH.
An excellent animation: www.eyesight.org.
Contributing factors: aging, genes, diet, smoking,
Age-related macular degeneration (ARMD) is one of the
commonest causes of poor sight in developed countries.
Whilst the causes are different in different
people, certain factors may contribute.
The main factor is age.
"By age 85, 57.4% of [people have] AMD. Age, smoking, plasma HDL cholesterol, BMI, and female sex are associated with AMD. Elevated HDL cholesterol is associated with GA development." .Oph 14
||Age is the main factor.
||Contributes 32% overall, even passive
||related up to ~30%;
a high cholesterol from an unhealthy diet or genes
Klein (2010); Toothbrushing helps. (tooth decay promotes conditions such as rheumatoid arthritis) summary BJO16
||High blood pressure damages the circulation...target is 140 systolic
in clinic, 10 lower for diabetes. 10 lower at home. 120 at home
for diabetes. Best
below 120 2
medications often required.
progression to neovascular ARMD by 70%
||~50% is directly due to the genes we inherit, see and Gene
||a high fat diet 10% (2010)
||This causes cardiovascular
disease, and will contribute to macular disease.
In urban environments, ~8% of deaths are generally attributed to pollution BMJ 14
||Excess alcohol is also related to ARMD, see
||Strong sunlight contributes to ARMD;
and sunglasses protect, see. But gentle sun exposure increases vitamin
D production, and this will reduce the risk of many conditions such as
diabetes, osteoporosis, and prostate cancer. Retina16
CRP, dental caries, each contribute
|| Light skin increases risk Eye 2012.
|obstructive sleep apnoea
||Untreated obstructive sleep apnea hinders response to bevacizumab in age-related macular degeneration Retina 16 BJO 17
||AJO 16 2-4x risk
Some communities in Japan did not develop
macular degeneration as people aged, but as soon as they started eating
Western food the condition started to occur. Similarly, when Japanese
people move to Western countries, they develop the condition more frequently.
These observations suggest that the high fat, and type of fats, such
as saturated and trans-fats, the lack of protective fats
(omega 3s, from fish), and salt (by increasing blood pressure) increases
ARMD. Lack of exercise as we drive everywhere in Western countries will contribute.
We inherit these from our parents.
Genes are the genetic information that tells our body what chemicals
to make. Overall, our genes may contribute to more than 50% of ARMD. The
main genes have been found. NatGen 2006. Gene page. For example, these genes control the way used-up chemicals
are removed from the eye. Being long-sighted (hyperopic) is also a risk
A healthy lifestyle
A healthy lifestyle helps to prevent
age related macular degeneration. This is important for the younger relations
of age related macular degeneration sufferers:
- Overall smoking accounts
for 32% of ARMD. Even stopping at the age of 80 will reduce the
risk of developing the disease.
So if you have a relation with macular degeneration, try and stop as
smoking may make it develop earlier.
- Smoking increases the risk of macular degeneration about 3 times. Macular
degeneration occurs 10 years earlier in smokers.
- If you have macular degeneration, do try and stop. Even if you are
90 years old stopping smoking will help your eyes considerably.
- Passive smoking is also harmful: for instance, if your partner smokes
cigarettes a day, you receive 25% of the smoke, so that is equivalent
to you smoking 5 cigarettes a day. 28000
cases a year in the UK.
report and 2003
study . Lithuania Japanese China
- Passive smoking doubles the risk , personal smoking triples
the risk of both geographic atrophy and neovascular ARMD.
- Each cigarette increases the ARMD progression rate ~15%.
Blood Pressure & Exercise
- 30 minutes a day at least, walking, or more active
exercise for younger people, reduces
risk by 70%: 2006
- Exercise may help by preventing hardening of the
30 minutes walking a day (regular walking)
three times a week will reduce ARMD risk by one third, compared to people who don't walk or exercise
and who drive everywhere.
- A low blood pressure helps. A level of 140/85 or below is likely
to be best. Blood pressure is written as '140/85', with the systolic/diastolic.
Above 115 (systolic) the risk of heart disease increases. See the evidence and more. Macular
haemorrhages are more likely with high blood pressure. More evidence Eye.
- Obesity is also a risk factor see.
- A low
salt diet is important Salt and more than 2 units of alcohol
a day may cause blood pressure to rise.
Too much may contribute indirectly
by increasing blood pressure, and is related to ARMD, see.
Blood pressure rises after drinking (opposite...drinking 4 pints/bottle
gram of alcohol puts systolic blood pressure up 0.24mmmHg, diastolic
0.16 mmHg. This means 1 pint of beer (2 units, each unit 8g alcohol) with
16gm of alcohol, drunk every day, will put the systolic blood pressure
up (16 x 0.25=) 4mmHg.
Experts recommend a healthy diet.
5-9 portions of fruit/vegetables
a day, with portions of different colours
Fruit/vegetables prevent 36-50% of ARMD see, see and see (fruit & vegetables
lower homocysteine levels, and this improves blood flow) BMJ 15.
Pulses like beans are fine. Bread, pasta, rice and potatoes provide 'energy'.
Vegetarians have lower blood pressures and healthier lipid levels, see .
A healthy diet reduces homocysteine levels, which
are associated with ARMD.
Certainly saturated fats increase the risk of ARMD; and fish and
polyunsaturated fats halve the risk. Avoiding certain fats helps, with
strong evidence here (explained more clearly here for heart
disease). Nuts may help prevent ARMD (small amounts...they are fattening).
Lutein and Zeoxanthin supplements slow down progression on average 10%, AREDS 2, 20% if diet is poor.
As the macula is the most chemically active area in the body, with the greatest oxygen demand, it has been thought that antioxidants such as vitamins may play a critical role.
The retina contains the pigments carotenoids lutein, xeaxanthin, mesoxanthin.
Lutein is in dark green leaves such as kale and spinach, and most of us do not eat enough. Xeaxanthin is in orange peppers, corn, nectarines and oranges (and other yellow/orange fruits/vegetable).
"Higher dietary intake of lutein/zeaxanthin was independently associated with decreased likelihood of having neovascular AMD, geographic atrophy, and large or extensive intermediate drusen" Seddon.
Oily fish twice a week reduces ARMD by 40%, especially
oily fish such as tuna, mackerel, sardines, herring, and salmon. A Japanese
diet may be helpful as above. Other omega 3 fats are helpful. See
Cholesterol & statins, patient and relatives
ARMD is commoner in people with higher cholesterol levels.
Atherosclerosis, caused by a high cholesterol, does contribute to ARMD, see . Statin treatment reduces macular degeneration. DK recommends them for people with ARMD. Naturally all relatives of ARMD patients should address this issue
of fat levels in the blood, sticking to a low fat diet with plenty of
exercise, avoiding obesity, just as described on this page for ARMD patients. Statins may not help
Macular pigment density is inversely related to ARMD: the thicker the pigment the less likely the condition.
- this explains why the condition is much commoner in Caucasians with blond hair and lighter coloured retina
- increasing the pigment with lutein may delay the condition Acta 2012 Eye 2012
- ARMD is unusual in Afro-Caribbeans,
and this may be because the 'elastin' layer is thicker.
- Especially in
wet ARMD with CNV, the elastin layer acts as a barrier to the growing
CNV (new vessels). Elastin is part of Bruchs
Cataract surgery and Vitreous changes
One paper suggests cataract
surgery leads to an extra 4-5 times risk of developing
neovascular macular changes or dry ARMD. Another states this is not so AREDS
25. Certainly patients
with early ARMD undergoing cataract surgery should be warned of symptoms,
that is distortion or changes in central vision, and attention should be
sought in a few days. Also.
If the vitreous is separated from
the macular the risk of CNV is significantly reduced AMJO
Wet ARMD (exudative/leaky)
(vascular endothelial growth factor)
blood vessel growth
leakage..blood and fluid
give anti-VEGF drug
leakage stops for a while
In wet ARMD, new vessels grow under the central retina
in the macular area, causing retinal leakage and swelling. (CNV..choroidal neovascularisation). The blood vessel frowth seems to be part of the eye's 'healiing' response to ack of oxggen/damage. The damaged retina releases a chemical VEGF (Vascular
endothelial growth factor). The VEGF
stimulates blood vessel growth, to produce the different types of wet
ARMD. In addition, the new blood vessels leak, causing fluid under the
retina in these condition.
The network of blood vessels usually progresses to cause a scar in the macular area. If the scar
is small, sight is reasonable; but if large, the sight can be very poor. It is very difficult to predict whose dry ARMD will progress, but
the risk factors include those mentioned above (soft drusen, high blood
pressure, smoking, poor diet, lack of exercise). This is described below.
There are different types of wet ARMD
Classic neovascular ARMD
New vessels growing under the central retina in a 'classic' pattern:
Anti-VEGF treatment needed. enlarge Photo (case 12)
When blood vessels grow under the macula, this is termed choroidal
neovascularisation (CNV). When the new vessels are seen easily on a fluorescein angiogram, they
are called 'classic CNV': they look like a net of blood vessels.
When a doctor looks in the retina looks elevated, there may be tiny
haemorrhages, a grey area, or exudates. Severe . In milder cases vision may still be good. The condition may develop over days or weeks, with increasing distortion
or blurred central vision. If this process is early you can still read,
but if it becomes severe reading with any magnifier is impossible. Treatment is based on anti-VEGF drugs, although other treatment are available
This is usually a serious type of macular degeneration, serious
because it can cause very poor central vision. It never blinds in the sense
that you cannot see light and dark, but in its serious form it can
damage the central vision so you can only see fingers or even the movements
of hands. Once again, the side vision will normally be good, so you
should always be able to walk around the house.
|ARMD progression rate
and relative risk of smoking
Sometimes a feeder vessel is visible, and on occasions it is possible to laser this.
'Occult' CNV type 2 (no 'PED')
In this type of ARMD, there
are new blood vessels, but they are not clearly seen with the angiogram. 'Occult' CNV
is the term given to a specific 'blotchy' appearance of the
angiogram. Occult ARMD is probably an early phase of classic, see .
Occult and classic patterns can occur together. Anti-VEGF drugs generally help. The symptoms of this type of CNV are the same as 'classic
CNV', except the condition takes longer to develop. Without treatment, this type 2 occult CNV usually turns into classic CNV over the next months
or years, to cause poor central vision.
Vascularised PED: (Occult CNV type 1)
PED..pigment epithelial detachment type of wet ARMD, with CNV (choroidal
neovascularisation): occult type 1. This condition usually progresses,
but progression rates are very variable.
In this type of wet ARMD the damaged area looks like a dome, but in addition fluid leaks under
the retina, hence the term 'wet'.
Anti-VEGF drugs generally help. The PED may reduce in size with treatment, and treatment will reduce intraretinal and subretinal fluid. Retina 2011. Occasionally
may 'rip', causing more loss of sight Eye 2011. Overall, 15% of PEDs rip, but the risk is proportional to the PED size, so a large PED is much more likely to rip. The rip typically occurs 2 months after starting Lucentis. The rip may not cause that much visual loss initially, but central vision may get worse over time.
November, 7 months later, a PED has developed, with a retinal haemorrhage. Also, intraretinal and subretinal fluid.
Patient, age 86, April, reasonable vision
Photo / OCT show drusen, hard and soft enlarge
- ARMD with a PED is classified as 'occult' CNV, type 1. Outcomes Eye 11
- Look for polyps, see PCV.
- photo case
9 r/l left case.
- There are 3 types of PED, reviewed here (avascular,
- photo avascular ped
- intraretinal cysts indicate a poorer response BJO14
- combined with geographic atrophy BJO 14
- treatment helps stabilize/improve SIO 15
- fluid fluctuates with injections every 2 months
- serous PEDs respond better Retina 16; switich antiVEGF if response poor.
- incomplete response to antiVEGF AJO 16
Polypoidal choroidal vasculopathy
This is another type of CNV. The condition is seen as a branching choroidal network of vessels with vascular dilatation.
- more common
in Chinese and
- The choroidal neovascularisation often occurs with a serous haemorrhagic PED.
- Polypoidal choroidal vasculopathy page.
- multiple PEDS, subretinal haemorrhages, visible polyps: deep orange lesions
- lipid exudates, subretinal fluid, RPE atrophy, peripapillary lesions
- classic & occult cnv, peripheral lesions: Features see
- distinguishing polypoidal choroidal vasculopathy from typical neovascular age-related macular degeneration based on spectral domain optical coherence tomography Retina16
Other types of wet ARMD
Pigment epithelial detachments
PEDs are present in different types of ARMD, but the caues are slighty different. The treatment depends on the cause. The PED is a dome of fluid under the pigment layer of the retina.
Hereare the different types of PED, some of which were discussed above:
3 Types of choroidal neovascularisation
- described here well
- results of angiographic OCT..all the articles in this journal Retina 15
Serous (avascular) PED
This is another type of PED, without any vascular element. In younger
patients this is usually part of Central Serous
Retinopathy. In older patients this is usually part of 'dry' ARMD, and
there may have been obvious 'dry' changes visible before this develops. Anti-VEGF treatment is not helpful (Eye
2010). Perhaps a serous PED in an older patient is better thought of as half way between dry and wet ARMD.
However, if the other eye has had wet ARMD, then such an eye is at very high risk of wet ARMD itself. Eye 2012 . It is probably safer for such a patient to have regular OCT examinations, perhaps every 3 months: as yet there is no evidence to prove that this will help, but logically it will help by detecting very early disease that is much easier to treat.
The PED is a dome of fluid under the pigment layer of the retina. there is a 'PED' only, no leak
'PED', with a leak under the retina (shown here) or in the retina
of vision and other symptoms:
dry ARMD changing into wet ARMD
How would you know if you have the 'neovascular' type of age related
macular degeneration? Some symptoms suggest you may be developing the problem:
- distortion of vision, where straight lines such as window frames
appear bent as shown below
- a feeling as though you are looking through water
- distortion only occurs in 10-50% of patients
- 7/8 patients have no symptoms in the early stages BJO 2011
- amsler helps with training Eye 2012
- Amsler helpful Eye14
- strategies for early detection CO14
- need to detect early BJO 16
If you do develop distortion of vision you usually need to see your
optometrist or ophthalmologist and have an OCT scan within a few days. See the amsler test below. Your ophthalmologist will recommend an OCT scan, and this shows the wet ARMD immediately.
In addition may recommend tests such as a fluorescein
angiogram. The angiogram tells the doctor if there are new vessels,
where they are, what type they are, and what type of treatment if needed.
Wet ARMD progresses 4 times faster (a 400% increase in progression
rate) in smokers.
Dry ARMD may develop into 'wet' ARMD (4%/year).
In wet ARMD, leaks develop,
and new vessels start to grow right through the retina.
Occasionally wet ARMD develops without dry changes, although usually
there is an area of retinal damage that triggers the process. photos
There may be a trigger factor such as inflammation, that triggers the conversion of dry to wet. (For example. teeth decay bacteria have been implicated.)
Distortion of straight lines which may
start to appear crooked over a few weeks usually means the ARMD is
progressing. Sometimes this is due to the 'neovascular' ARMD developing,
and you are advised to be checked in case laser may help.
should be given the Amsler Grid test to use every day, or at
least once a week, at home. These
authors recommend this test, although personally I have found that
patients may still present late (this is a major problem). Patients are given a grid, told to look at the central spot with their
reading glasses on, using one eye at a time. If any of the adjacent
lines become bent or wiggly or distorted, then CNV (blood vessels growing
under the macula) may be present, and patients should see their optometrist, ophthalmologist
(or in Birmingham attend the Eye Centre Casualty, City Hospital). The test is explained well here . home device another Ophth14
Unfortunately visual changes follow changes that can be detected by OCT scans BJO 2011 CNV are detected
- 1/8 when the patient notices changes generally
- 1/3 when there are changes in the amsler grid
- 1/3 by reduced vision acuity reading a chart as compared with OCT. Monthly OCTs are necessary to detect recurrences!
- late presentation is common and linked to social deprivation BJO14
- a home device may be best Eye 16 see
the other eye, risks
Unfortunately age related macular
degeneration can affect the other eye. See healthy
lifestyle above: this may help. If you do notice a change in your sight,
see distortion above. See
a search . Risk
- The atrophic or dry type usually does occur in both
eyes, but remember this generally gets only worse slowly.
- There may be a gap of years before the process begins in the second
- If one eye has had wet ARMD, and the other eye has a PED, then screening with regular OCTs may help.
- If you notice the symptoms (central vision becoming distorted or blurred,
sometimes like looking through water) you should have your eye checked with an OCT scan:
Concerning neovascular or wet type ARMD:
- The neovascular or wet type can also affect the other
eye, at an overall rate of 90% over the next 5 years.
- High blood pressure, one large drusen near the fovea, 5 drusen in
the macular area, and retinal pigment epithelial changes each contribute
to this 90%.
- So if you have only one of these risk factors, such as 5 drusen and
a low blood pressure and don't smoke, then the progression rate is
90/4, that is about 23% over a 5 year period . If you have 2 risk factors,
- But if you have 2 risk factors (45% 5 year risk) and your partner
smokes 20/day, your risk is 45 x2 = 90% over 5 years...see
- The figure is 4 times higher for smokers, and twice as high for passive
smokers. (If smoking at 20 cigarettes/day.)
- the active phase may last 3-12 months, with the sight deteriorating
during this time, and after that they may be little change. Treatment
(laser & drugs) is needed during the active phase, and is of no
help later. Anti-VEGF treatment may be needed for 2 years.
Thanks to colleagues
- aspirin can lead to more aggressive wet ARMD etc, JAMA 2013
- Secondary prevention: there is strong evidence that its benefits outweigh the risks
- Primary prevention: risks and benefits. In patients who, under current guidelines, are eligible for treatment because of their 10-year risk of myocardial infarction or stroke, "the presence or absence of strong risk factors for neovascular AMD might tilt treatment decisions in one direction or the other."
- Other uses of aspirin: be cautious in recommending long-term aspirin to other patients, such as those requiring pain control.
Some other features of ARMD
Many types of macular degeneration progress to cause scarring. 'Dry'
types usually progress more slowly, but occasionally can cause very
poor central vision, but this is commoner in the 'wet types'.
If your conditions is severe wet scarring is likely.
Sometimes retina in the macula area can tear and shrink. This
is call a 'rip' or a 'tear' of the pigment epithelium. It may occur spontaneously
as part of wet ARMD, but can occur after PDT or anti-VEGF treatment, particularly if there is a large PED.
A rip may cause significant loss of central vision see. but the risks are only slightly
The chances of rip depend on how elevated
the PED is (the retinal
pigment epithelial detachment). For instance, an 840μ elevation
has a 50% chance of ripping. A 500μ elevation
has a 10% chance of ripping. Gelsiken
Case. Rip: separate page for printing.
Here is a summary of some of the abbreviations ophthalmologists use
in this condition:
|anti-VEGF / injection
||drugs that reduce growth and leaking from the new blood vessels under the retina in ARMD, or on the retina in diabetes etc. They are given by injection into the eye
||age-related macular disease = age-related macular degeneration = ARMD
||age-related macular degeneration
||easy-to-see neovascular ARMD (based
on angiogram) blood vessels growing under the retina and leaking
||choroidal new vessels (i.e. neovascular
macular degeneration, or 'wet'). Blood vessels growing through the retina
under the macula.
Also called CCNV.
|CNVM or CNVm
||a choroidal neovascular membrane, that is a network of CNV,
although in practice this means the same thing as CNV
||central serous retinopathy
||a type of aging change of the retina...tiny white spots/areas
||thinning (and other changes)
of the central retina
||indocyanine green angiography
||intraretinal fluid (an OCT scan finding)
||the centre of the retina that sees detailed vision like faces and reading
||similar meaning to wet armd
|OCT / scans
||optical coherence tomogram: a 3 dimensional photograph of the macula, called a scan
||hard-to-see neovascular ARMD (based
blood vessels growing under the retina and leaking (but the leakage is late)
||Polypoidal choroidal vasculopathy
therapy (for classic sub-foveal neovascular ARMD )
||pigment epithelial detachment,
a type of wet ARMD
||retinal angiomatous proliferation
||a pigment epithelial rip or tear
||Vascular endothelial growth factor...the main chemical that
makes blood vessels grow in ARMD
||Virtual macular clinic..patients attend for an OCT and the scan is interpreted later, and the patient contact if another anti-vegf injection is needed
||wet age-related macular degeneration, with CNV as above (blood vessels growing and leaking under the retina, usually under the macula)