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Good Hope Hospital Eye Clinic

Age Related Macular Degeneration (ARMD) pathology & treatment
David Kinshuck & Monique Hope-Ross

This is a very long page..see separate pages

This page.................................................................

Introduction

The causes

pathology

types of dry ARMD  

Distortion of vision and other symptoms:
dry ARMD changing into wet ARMD

'Wet' or neovascular types of ARMD

Further details

Low vision & Macula Disease

 


ARMD introduction

ARMD is usually a progressive condition, affecting the center of the retina and the centre of the vision. Invisible early changes occur, then usually some type of dry ARMD, such as drusen or geographic atrophy.

Later, the dry changes may progress, usually slowly, to cause more atrophy and damage to the central retina. The dry changes are bascially aging, wearing out of the central retina.

Then in some people, wet changes develop, with blood vessel growth and leakage in the macular area. These wet changes can be slowed down with anti-VEGF drugs (see this page or wet ARMD page).

Age-related macular degeneration is explained in more detail on other web-sites, such as the RNIB and NIH. This is an excellent animation: www.eyesight.org. This page summarises our current knowledge.


Contributing factors: aging, genes, diet, smoking, etc

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. 

 

age age is the main factor
summary  
smoking

contributes 32% overall, even passive smoking

diet related up to ~30%; a high cholesterol from an unhealthy diet or genes Klein (2010); Toothbrushing helps. (tooth decay promotes conditions such as rheumatoid arthiritis)
blood pressure high blood pressure damages the circulation...2010 target is 140 systolic in clinic, 10 lower for diabetes. 10 lower at home. That is 120 at home for diabetes.
Best below 120    2 medications often required.
exercise via blood pressure effects; regular exercise reduces risk by 70%
genes ~50% is directly due to the genes we inherit, see and Gene page

cholesterol

a high fat diet 10% (2010)

exercise reduces progression to neovascular ARMD by 70%
airbourne pollution This has been found to cause cardiovascular disease, and therefore is likely to contribute to macular disease. In urban environments, ~8% of deaths are generally attributed to pollution. More definitive proof is awaited, but may take years to obtain, especially the contribution of pollution to ARMD specifically.

alcohol

Excess alcohol is also related to ARMD, see 

sunlight

Sunlight exposure, especially the summer sun, contributes to ARMD; and sunglasses protect, see.  Some sunlight exposure is important...gentle sun exposure increases vitamin D production, and this will reduce the risk of many conditions such as diabetes, osteoporosis, and prostate cancer.

other Other pro-inflammatory states can influence the condition, such as chlamydia  High CRP, Ophthalmology 2010
macular pigment ARMD is much commoner in Caucasians...the lighter the skin or the least retinal macular pigment is related to risk. 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 membrane link

 


Other countries

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) in our diet, the lack of protective fats (omega 3s, from fish), and salt (by increasing blood pressure) increases the number of people with ARMD. Lack of exercise as we drive everywhere in Western countries will contribute.

pie chart illustrating factors contributing to ARMD

click here for full size image

 


Genes

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. We will soon be able to work out who is at risk...the main genes have been found. Tsee

See Gene page   The genes that may cause macular degeneration probably control the way used-up chemicals are removed from the eye. Being long-sighted (hyperopic) is also a risk factor

 


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:

 


Smoking
  • 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 body receives 25% of the smoke, so that is equivalent to you smoking 5 cigarettes a day. 28000 cases a year in the UK.
    See 2002 report and 2003 study . Lithuania     Japanese  

  • A new report here describes the risk of passive smoking (doubles the risk) and personal smoking (triples the risk) of both types of ARMD, that is geographic atrophy and neovascular.


  • Each cigarette probably increases the progression rate or ARMD ~15%

skoing increase the risk or ARMD 3-4 times

the risk of smoking and passive smoking and ARMD

larger

 

 


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 arteries.
    30 minutes walking a day for example...regular walking, for example, three times a week will result in less than a third of the amount of neovascular ARMD 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.

 

dancing and all other forms of exercise delay ARMD

 


Alcohol

Too much may contribute indirectly by increasing blood pressure, and is related to ARMD, see. Red wine may be healthier in small amounts).

Blood pressure rises after drinking (opposite...drinking 4 pints/bottle of wine).

Each 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.

after 8 units of alocohol blood pressure rises for 2 days

enlarge

 


Diet
Experts recommend a healthy diet.
  • This should include a variety of vegetables and fruit
    (at least 5-9 x 100gm portions/day) (2008)
  • low fat only dairy food
  • the minimum of trans and saturated fat
  • the minimum of red meat, as part of a balanced diet
  • oily fish ...2 small portions a week, Blue Mountain 2009, Australia 09 reduces aging
  • 1-2 hours exercise a day
  • A low salt diet is important
  • Vitamin D reduces risk, (Vitamin D increases with sunilght)  Archives 2011      Vitamin D
  • a Mediterranean or Japanese diet (as was 20years ago) will almost certainly protect. 
  • Losing weight (if overweight) reduces risk
  • Solid fats are harmful Eye 2011
  • plants sterols lower cholesterol food.gov.uk,  which foods
  • Zinc

Fruit/vegetables prevent 36-50% of ARMD see, see and see (fruit & vegetables lower homocysteine levels, and this improves blood flow).

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).

 

 

fruit and a healthy diet will sigificantly reduces the risk of developing ARMD

5-9 portions of fruit/vegetables a day, with portions of different colours
5 is a minimum..best 9 for men, 7 women, 5 children, see.

The Guardian (2005) reviewed healthy diets etc, here, here , here , here and so on.

See some epidemiology

 


Vitamin supplements

As the macula is the most metabolically 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 darg 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. These vitamins are in the 'AREDS2' supplements Lack of vitamins has been linked to macular degeneration

If you are unable to eat this many vegetables, AREDS2 supplements may help, but too many vitamins may be harmful.  

Age-Related Eye Disease Study--Results

The AREDS1 vitamins reduce ARMD by 25%. It is not known whether or not they help patients who have a healthy diet.

ICap (Alcon), is available in pharmacies and optometrists. This has lutein and other vitamins in, and had been recommended by some ophthalmologists. Beta-carotene supplements are not recommended for smokers, as they may contribute to lung cancer. I Cap is similar to the AREDS vitamins that reduced ARMD risk by 28%. zeoxanthin , Against., BMJ
These supplements may not help (see), as some experts advise that people with a healthy diet may be harmed by taking vitamin supplements. A review (2006, Drug and Therapeutics Bulletin, not free online) recommmeded a healthy diet including green vegetables diet was preferable to supplements.
If you have a healthy diet, ophthalmologists disagree. More details of food composition here.

 


Oily fish
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
oily fishes reduces ARMD  ~40%

 


Cholesterol & statins

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. See    see,   Although statin tablets are not yet formally recommended by all agencies, this author would recommend them for people with ARMD.  
This paper & another found no benefit, so it is difficult to be certain.

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.

 

 

 


Cataract surgery
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.


Vitreous changes
If the vitreous is separated from the macular the risk of CNV is significantly reduced AMJO 09. This is a new observation.

 


The pathology of ARMD
(Age-related macular degeneration)

Dry ARMD progresses over many years (this page). In some types of dry ARMD progression may be very slow, but it may be quicker in other types. Sight does deteriorate, but most people manage to cope well, although reading is difficult and life may be different.

Dry ARMD may progress to the 'wet type', but this is not always the case.

Wet ARMD  begins as new vessels growth in the macular area, causing retinal leakage and swelling. Seepage. It progresses to cause a scar in the macular area. If the scar is small, sight is reasonable; if large, the sight can be very poor.

Imagine your retina has five layers. Normally this retinal appearance stays constant even in old age, but changes may develop as you get older.

retinal layers

Invisible changes

As we get older, changes develop in the retina. The bruchs membrane thickens and the choroidal blood vessels change. see diagram

The thickened bruchs membrane prevents waste products leaving the retina (see animation and the link), and also prevents nutrients entering. This is thought to be a direct cause of the condition. Lipofuscin (type of fat) accumulates in the retinal pigment epithelium; this damages the pigment cells which eventually die.

The choroidal circulation changes...the blood vessels become larger but fewer. This is probably mainly due to a 'hardening of the arteries' that happens elsewhere in the body, particularly with a Western diet.

The invisible changes progress to cause dry ARMD,

  • patches of extra thin retina develop, just as though the retina is 'worn out .  Often the patches of thin retina gradually get larger, reducing sight.
  • Deposits of waste products may develop, called drusen
  • pigment changes develop
  • changes in the choroid pseudodrusen / reticular drusen
  • the dry changes may convert to 'wet ARMD'

These changes are described with photos below.

thickening of bruchs membrane with age in macular degeneration, diagram

 


What does a person notice with these early changes ?
  • difficult seeing in dim light
  • difficult seeing in bright light
  • slow recovery in bright light
  • poor central vision when you wake up

If you notice these problems then you are probably at risk and need a check from an optometrist or ophthalmologist. If there are no visible changes, the author would strongly recommend a healthy lifestyle as prevention...it helps your general health in any respect. (This section: after Prof. Bird).

 


Types of 'dry' macular degeneration

 


Progression of 'Dry' macular degeneration

Once the invisible changes above develop, the dry changes develop.

  1. drusen develop. These are deposits of various types of fatty (lipids) substances.
  2. the drusen may may small and hard...in which case progression is slow
  3. alternatively the drusen may soft, in which case the condition usually progresses
  4. the soft drusen cause thinning of the retina and loss of sight
  5. the degree of sight loss is very variable...depending on the amount of retina that becomes thin. If the very centre of the macula is affected (the fovea) the reading becomes a problem. Sometimes the fovea appears healthy, but the fovea is surrounded by thin 'atrophic' retina....reading may still be a problem as the images of letters that are being read fall  on the damaged non-seeing retina...so you can only see part of words at any one time.
  6. the thinning of the retina is called 'geographic atrophy'. Atrophic changes are present in most of the of the 'dry' types of ARMD as below.
  7. A number of patients with the dry geographic atrophy or soft drusen also develop wet  macular degeneration. Wet ARMD occurs when blood vessels grow under the macula, and leak and bleed.
    But in some ways it is best to consider wet and dry as different conditions, with different genetic and environmental 'causes'.
  8. Eye 2011...risks should be addressed.

atrophic macular degeneration

The retina becomes very thin, just as though it is worn out. The patches of such thin retina do not 'see', so the central vision becomes patchy. Essentially it is a type of wear and tear.

Dry types of macular degeneration can get very slowly worse, but only affect the macular area. The rest of the retina, which helps you see at the sides so you can walk round the house, always stays good. The progression is a usually a very slow process taking years.

This movie  is excellent.

If this wear and tear is mild you may be able to read and even drive, although it takes a little longer to adjust to different lighting.
Often it is a little more severe, and reading is difficult, and driving is impossible. TV is not too bad if you sit close: this is discussed in Hints & coping

Some types are non progressive, and not discussed here in detail (such as old macular holes).
Every person is different, and often it is very difficult for your doctor to predict what will happen to your sight.
Sometimes changes can occur more rapidly, and this would suggest that you are also developing the 'wet' type of ARMD as below. See www.macula.org

The appearance of the retina may be same in different patients (phenotype.) But in fact each person's condition (even though it looks the same to the doctor on the photographs or scans may have different factors such as different genes (genotype).
This is one of the reasons it is so difficult how each person's condition will progress. 2011: no treatment yet.

see photo

Patchy vision in atrophic macular degeneration

 

  • the same retinal appearance in different patients may have different 'causes'.
  • it may help to consider wet and dry macular degeneration as 'different' conditions.
  • whilst wet usually follows dry ARMD, only one out of three dry ARMD patients develop wet
  • by addressing all the risk factors above, especially smoking, the progress of dry to wet may be stopped

 


Drusen

There are different types of drusen. They are one of the signs of dry ARMD, and soft and pseudodrusen/reticular predisposed to wet ARMD..

Hard drusen: If they are well defined with a sharp edge, the sight is likely to stay good.

Soft drusen: If they are a little like cotton wool, they are more serious as they may lead to more serious disease with 'exudative changes' as below: prevention is most important (see above). Reference.

hard and soft retinal drusen

and another large one. another See hard drusen (right) & case.

 

soft drusen...see white arrow

enlarge...white arrow is pointing to one of the large soft drusens
(Soft drusen, 6/6. vision slight distortion, patient born 1936)

 

Drusen look like little white spots in the retina. See tiny drusen. These are accumulations of material, probably some waste products of the retinal cells. These are common, and do not usually affect the sight.

The accumulation occurs as bruch's membrane becomes thicker and prevents the free flow of materials to and from the light or photoreceptors layer.

Also, the retinal pigment cells accumulate lipofuscin. This pigment will also slow down the passage of chemicals to and from the retina.

People with a lot of drusen in the central retina have slightly reduced sight. If there are a few drusen you may be said to have very early 'dry' macular degeneration.


retinal drusen

Drusen are slightly related to cholesterol levels. It is logical that reducing the cholesterol will slow down drusen development and therefore slow macular degeneration.Drusen are linked to choroidal blood flow reductions Retina11

UK cholesterol target is 4.5mmol/l, and the World Health Organisation recommends less than 3.5 as ideal, although risks increase above 2.5.
DK therefore advises patients with drusen to try and reach these targets, even if that means using statins (as long as the patient can find a statin that without side effects [statins increase diabetes and cataract risk])
. This is especially important for softer drusen as above.

 

Pseudodrusen / reticular drusen

Reticular drusen/ pseudodrusen are vascular changes in the choroid, which appear as RPE changes on the OCT. However, this is an artefact...the changes are in the choroid risk.

Such drusen may lead to wet ARMD: they are related to chromosome 10 gene differences,

See  Photo   Autofluoresence is helpful.

See types of drusen,  risks and epidemiology. Soft drusen are inherited: see CFH Y402H. Drusen come and go BJ0 2010   Types of drusen with photos BJO 2011.Basal laminar drusen OCT 2010

pseododrusen = reticular drusen: predispose to wet ARMD

 


Geographic atrophy (GA)

(on separate page)

Areas of thin retina develop, like the patterns of countries of the world. The areas get bigger over years, slowly causing more damage to the sight. Geographic atrophy is the main type of dry ARMD. See a photo

Geographic atrophy (GA) accounts for a third of ARMD, with new 12,000 cases a year in the UK. It is believed to be caused by retinal pigment epithelial atrophy leading to cell death. It is best examined with the autofluorescence technique but this is seldom available Retina 2010. There is no treatment available yet, although trials are in place. FAF photo. Atrophic myopic macular degeneration is usually similar.

We now know here that the risk of passive smoking (doubles the risk) and personal smoking (triples the risk) of both geographic atrophy. See genes and here.

geographic macular degeneration, diagram

It is now clear that GA can lead to wet ARMD, particularly if the GA has an irregular outline ('lobulated'). There is a gene contribution from chromosome 10 genes. This is a more rapidly progressing form, with basal laminar deposits.

So GA is not one disease...it  is the end stage of many different types of 'dry' ARMD, and an intermediate type in others. It is still not known whether the primary priblem is in the retinal pigment epithelium, choroid, or photoreceptors. GA affects 1/3 people >75y.

geographic ARMD with cnv

enlarge...white arrow is pointing to the geographic change. This progressed over 7 years. Just recently, sight deteroirated, and there are cnv (wet ARMD) which has just begun (blue arrow). Patient male, born 1932. (Only 7% of GA leads to cnv).

Autofluorescence can be used to predict the progression rate.
Lipofuscin deposits demonstrate autofluorescence, with the stressed affected retina showing up white, the atrophic retina black. Crystalline and soft drusen may turn into areas of GA.
Night vision, age, smoking, blood pressure etc can be used to predict progression. Rods tend to be affected first, then cones.

 


Mixed

Changes may include thinning of the retina, drusen, pigmentation, or thickening of the retina. There is a variable outcome. ‘Prevention’ may help.

photo     photo    photo

 

mixed macular degeneration, diagram

Adult onset foveomacular vitelliform dystrophy (AOFVD)

This is a type of dry macular degeneration (ARMD). The damage is confined to the centre of the macula, the fovea. This is a very small central area, and has been described by Gass, and here. Generally the prognosis is good.

However, the retina does become thin in the affected area, and the sight may get slightly worse with age.
A few patients do eventually develop wet ARMD, or other problems. However, this is not part of the condition, and is really coincidental.

See  

 

 

macular degeneration of gass, diagram

The centre of the retina (the fovea) is affected,
leading to problems with central vision
.


Distortion 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

If you do develop distortion of vision you usually need to see your ophthalmologist or have ascan at your optometrists within a few days.In the UK you may need to discuss this with your GP, or in a large city attend the Eye Emergency department. 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 

 


Amsler grid test

Patients 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 glassses 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 ophthalmologist (in Birmingham attend the Eye Centre Casualty, City Hospital).  

The test is explained well here . A home device enabling early detection of wet ARMD Retina 2010.     

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!

distortion of sight

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.

 


ARMD and the other eye

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 from drusen.

The atrophic or dry type usually does occur in both eyes, but remember this generally gets very slowly.There may be a gap of years before the wet ARMD develops in the second eye.

 


Wet ARMD (exudative/leaky)

There are different types of wet ARMD

In wet ARMD 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 condtions.

 


Vascularised retinal pigment epithelial detachment (PED): Occult CNV type 1

In a few people, the dry macular degeneration turns into this type of ARMD. Occasionally, there may have been no obvious 'dry' changes visible before this develops.

In this type the damaged area looks like a dome. Fluid leaks under the retina, hence the term 'wet'.

Anti-VEGF drugs are used, although is not always effective.

Occasionally these drugs can cause the retina to '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.

The PED will not reduce in size with treatment, but treatment will reduce intraretinal and subretinal fluid. Retina 2011

Generally ARMD with a PED is classified as 'occult' CNV, type 1. Outcomes Eye 11

Avascular PED

There 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 ARMD, and is classified as an avascular or serous ped: anti-growth factor treatment is not helpful (Eye 2010).

However, if the other eye has had wet ARMD, then such as eye is at very high risk of wet ARMD itself. Eye 2012  Really (I suggest) that such eye should 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.

occult cnv with a PED (a type of macular degenerationa 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.

a photo  case 9 r/l left

See a case. There are 3 types of PED, reviewed here (avascular, occult, polypoidal).

 

photo avascular ped

serous and vascularised peds
 there is a 'PED' only, no leak enlarge

'PED', with a leak under the retina (shown here) or in the retina

 

 


‘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 are used and results are generally good.

The symptoms of this type of CNV are the same as 'classic CNV' .

Without teatment, this type 2 occult CNV usually turns into classic CNV over the next months or years, to cause poor central vision.

Large occult membranes can develop haemorrhages with anti-VEGF treatment (BJO 2008).

 


Classic neovascular ARMD
(also called ‘classic CNV’)

Some dry types of macular degeneration progress to form this type of wet ARMD.

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).

When blood vessels grow under the macula, this is termed choroidal neovascularisation (CNV or CCNV).

When the new vessels are seen easily on a fluorescein angiogram, they are called 'classic CNV': They look like a net of blood vessels.

Photo (case 12)

When a doctor looks in the retina looks elevated, there may be tiny haemorrhages, a grey area, or exudaes. This photo is a severe case. 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 mild you can still read, but if it becomes severe reading with any magnifier is impossible.

Treatment, if possible, includes the anti_VEGF drugs Avastin & Lucentis. Laser PDT  may help in addition.

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: see distortion..

This is usually a very serious type of macular degeneration, serious because it can cause very poor sight. 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.

The CNV grow at 20�/day, reaching 3000 � in 6 months. They can be extremely difficult to see in early stages. Small membranes gain, on average, 5 lines of vision with the Lucentis.
The biggest problem is detecting them early, and much work ('Replacing the Amsler Grid")   is being carried out to detect early membranres. OCT is essential to diagnose the condition early.

The condition is occasionally unresponsive to treatment. Surgery/other treatment

early cnv (macular degeneration)

New vessels growing under the central retina in a 'classic' pattern: PDT treatment may help

enlarge

  ARMD progression rate and relative risk of smoking see
geographic neovascular

active smoking

x 3.4 x 2.5
passive smoking x 2

 

photos / ffa
same patient 3 months after pdt

another classic
same patient other eye...disciform scar

CNV due to sarcoid membrane other healthy eye
(thanks to Ajith Kumar/BMEC)
treatment with PDT

 


Polypoidal choroidal vasculopathy

The condition is seen as a branching choroidal network of vessels with vascular dilatation. It is more common in Chinese and Afro-Caribbeans.

The choridal neovascularisation often occurs with a serous haemorrhagic PED. It is discussed in more detail here.

Features see
  • multiple PEDS
  • subretinal haemorrhages
  • visible polyps: deep orange lesions
  • lipid exudates
  • subretinal fluid
  • RPE atrophy
  • peripapillary lesions
  • classic & occult cnv
  • peripheral lesions


Myopic CNV

In this type of myopic macula disease, new vessels grow in the macula area. 5% of highly myopic eyes (more than -6.00d) develop CNV.

This is similar to wet ARMD, but in myopia it may occur in much younger people. However, it is much commoner in older people with myopia.

These new vessels are called 'CNV'...choroidal new vessels or choroidal neoovascularisation, as the blood vessels originate in the choroid and grow under the retina.

The CNV cause retinal leakage and swelling. The condition progresses to cause a scar in the macular area. If the scar is small, sight is reasonable; if large, the sight can be very poor.

The long term prognosis is not good: most eyes develop less than <6/60 vision. Younger patients have a better prognosis..the CNV get walled off.

All types of wet ARMD (CNV) will progress 4 times faster in smokers, a 400% increase. In addition to smoking, high blood pressure, poor diet, lack of exercise increase the likelihood of progression and progression rate.

Treatment/details page

early cnv (macular degeneration)

New vessels growing under the central retina in myopia  (similar anatomically to regular CNV)     enlarge      photo    photo    

Myopic CNV Arevalo , Ruiz-Moreno,     Avastin, Chan 2008     Wakabayashi 09

Some CNV are related to newly developed areas of lacquer cracks Eye 2011.

See treatment of myopic CNV.  

 


Extensive submacular haemorrhage due to CNV (choroidal neovasularisation...wet amd)

Occasionally large haemorrhages develop in the macular area. These are more likely in smokers, aspirin/anticoagulant users, especially if there is hypertension, or in very elderly patients.

Various treatments have been tried.

www.optometirc.com macular haemorrhage

 


Extensive submacular haemorrhage: gas tampanade

Perhaps the best treatment at present is gas tampanade. (Sacu 09).

Injection of tissue plaminogen activator followed by gas often displaces the blood. By displacing the blood, vision may imporve, but also there will be less maular scarring and better sight in the long-term.

 

 

 

 

 


Laser and anti-VEGF injection treatment

If the choroidal new vessels (CNV) are not in the very centre of the retina, regular laser can help. (Laser is a very bright light that makes tiny burns at the back of the eye.)

This appearance is called classic extra-foveal CNV.

This treatment is only suitable if the CNV are well away from the fovea. Laser is not suitable near the fovea, as over the years laser burns expand and this can reduce central vision.

 

 

classic extra-foveal CNV

If the area of neovascular ARMD (CNV), shown as the red area, is not under the very centre (the yellow spot, called the fovea), and laser was used.

Most people with neovascular ARMD have CNV in the centre of the retina. This appearance is called sub-foveal CNV.

In general treatment will be with Avastin (or Lucentis) anti-VEGF drugs  The drugs are given by injections in the eye itself about 8-12 times a year.

Avastin/Lucentis usually cause regression of new vessel growth. But unfortunately, after 4 weeks, the effect of the drugs wears off, and then the new vessels start to grow again, needing repeated treatment. Such injections may be needed every month for years.

Early CNV responds best, needing fewer injections. Here is an up to date treatment plan.

classic subfoveal CNV

CNV under the fovea
(causing serious visual problems). 'subfoveal CNV'.

 


Laser & other treatments for neovascular ARMD

There are other treatments for neovascular ARMD (CNV), such as surgery, but apart from PDT laser these are not very successful and not in general use:


PDT discussed here   This may be used in addition to Avastin/Lucentis.
Surgery inpractical etc (except macular translocation)
radiotherapy available for research patients, eg in Leamington
Feeder vessels can be lasered, with/ without other treatments.
Macular haemorrhage Intra-vitreal gas and TPA effective with a large fresh macular haemorrhage +/-laser later.

 


Scarring

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 (example) scarring is likely.

See a scar another. another large

macular scar diagram ARMD


ARMD and risks for the other eye
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 from drusen.
  • 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 eye.
  • If one eye has had wet ARMD, and the other eye has a PED, then screening with regular OCTs may help.

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, 45%.
  • 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 immediately below.
  • 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.
 

 


Rip / tear

Sometimes the 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. A rip causes significant loss of central vision.

See a case, with reports  a pigment epithelial rip   (thanks to Ajith Kumar/BMEC). Even the new drugs can cause the retina to 'rip', but the risks are only slightly increased.

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 2009

 

Rip: separate page for printing.

 


Abbreviations

Here is a summary of some of the abbreviations ophthalmologists use in this condition:

 

CNV choroidal new vessels (i.e. neovascular macular degeneration, or 'wet'). Blood vesssels 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
ARM age-related macular disease
ARMD age-related macular degeneration
PDT photodynamic therapy (for classic sub-foveal neovascular ARMD )
Occult CNV hard-to-see neovascular ARMD (based on angiogram)
blood vessels growing under the retina and leaking (but the leakage is late)
Classic CNV easy-to-see neovascular ARMD (based on angiogram) blood vessels growing under the retina and leaking
dry ARMD thinning (and other changes) of the central retina
PED pigment epithelial detachment, a type of wet ARMD
Rip a pigment epithelial rip or tear
VEGF Vascular endothelial growth factor...the main chemical that makes blood vessels grow in ARMD
RAP retinal angiomatous proliferation
OCT / scans optitcal coherence tomogram: a 3 dimensional photograph of the macula, called a scan
VMC Virtaul 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 (armd) wet age-related macular degeneration, with CNV as above (blood vessels growing and leaking under the retina, usually under the macula)
neovasularisation similar meaing to wet armd
macula the centre of the retina that sees detailed vision like faces and reading
anti-VEGF / injection drugs that reduce growth and leaking from the new blood vessels under the retina in arnd, or on the retina in diabetes etc. They are gvine by injection into the eye
GP general pratitioner
drusen a type of aging change of the retina...tiny white spots/areas
   

 


Links
some facts, USA,

http://www.nei.nih.gov/health/maculardegen/armd_facts.asp

support, USA Macula Degeneration Support Website
animation

http://www.eyesight.org/Macular_Degeneration/Pictorials/pictorials.html     
( very helpful)

anatomy http://webvision.med.utah.edu/book/part-ii-anatomy-and-physiology-of-the-retina/
more facts, UK Royal National Institute for the Blind
support, UK

http://www.maculardisease.org       [email protected] 
The Macular Disease Society
PO Box 1870
Andover
SP10 9AD
Tel: 01264 350551

ARMD web site http://www.armd.org.uk/index.html

photos Some useful photos http://eyephoto.ophth.wisc.edu/.
depression this is common and can be prevented/treated   See our LVA page

thanks to

Photos thanks to Good Hope and BMEC photographers/staff

The address of this site ('org' changing to 'nhs') is changing from http://www.goodhope.org.uk/departments/eyedept/ to http://www.goodhope.nhs.uk/departments/eyedept/
Eye website feedback -- Heartlands -- page edited October 2011 -- Public transport to Good Hope --