Quick Eye Health Guide

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Cataracts »

Age Related Macular Degeneration »

Glaucoma »

Floaters »

Cataracts are one of the most common eye conditions in the elderly and affect most people to varying degrees after a certain age.

The simplest description of cataracts is a clouding of the lens, which is a part of the eye that focuses light. Having cataracts can be a bit like looking through a fog. It can not only affect the clarity and contrast of your vision but colours also look faded. This is why when patients have had their cataracts removed one of the first things they notice is how vivid colours look. As cataracts generally take a very long time to develop, people don’t realise the colours they have been missing out on until they have them removed.

Common causes of cataracts

- Advancing age
- Trauma or injury to the eye
- The result of other conditions such as glaucoma or diabetes
- Long term steroid use
- Birth defect. Some babies are born with cataracts
- Smoking and excessive alcohol intake
- Excessive UV light, i.e. too much time unprotected in the sun

What symptoms do you get?

- Cloudy or blurry vision
- Colors seem faded
- Glare. Headlights, lamps, or sunlight may appear too bright. A halo may appear around lights
- Poor night vision.
- Double vision or multiple images in one eye
- Frequent prescription changes in your glasses
The operation

Cataracts generally need to reach a certain level before they are removed. The optician would normally judge this level based on which line you can read on the chart. However, other factors also need to be considered such as whether you drive, how much the cataract is bothering you and if there are other eye conditions. You would only be referred for a cataract operation if you want to have them removed. You may decide that you are happy to put up with the blur in your vision.

If the optician did decide to refer then you generally have to wait around 3 months on average before having the operation. If both eyes need to have the operation they would operate on one eye then wait a couple of months before operating on the other eye.

The operation is usually a simple 20 minute procedure and you are normally in and out of hospital on the same day. Although it is a routine procedure, as with any operation there is always a risk of complications, which the doctor will discuss with you.

The procedure itself is fairly straightforward. In the most common procedure, also known as ‘phaco’, the eye is anaesthetised with drops so you don’t feel anything. Then a small probe is inserted into the eye which emits ultrasound. This breaks up and dissolves the natural lens in your eye so that it can be removed by suction. Then once the natural lens has been removed it is replaced with an artificial lens which is clear. This artificial lens can often be designed to correct your vision in the distance. That’s why after having a cataract operation many people who have always needed glasses for looking in the distance find that for the 1st time they can walk around without specs. However they would usually still need glasses for reading.

After the operation the doctor will normally advise to wait 6 weeks for the eye to settle down before having an eye test. The procedure normally causes the prescription to change so you would need to have another sight test to assess the change.

After the operation in a small number of cases the capsule surrounding the new lens becomes cloudy. It can be a few months or up to a couple of years before this occurs. This is not the cataract coming back again, although this is what it seems like. Again, it is a simple procedure to correct this problem if it occurs. All the doctor would do is use a laser to clear a hole through this capsule and the vision becomes clear again. This can only occur once in each eye. Once it’s clear it doesn’t come back again.

Is there anything you can do to protect your eyes from cataracts?

As mentioned it is thought that sunlight can be associated with cataracts. So where possible always try to wear eye protection in bright lights.

Also having a healthy well balanced diet may have a link to preventing cataracts to a certain degree, although this doesn’t seem to have such a strong connection with cataracts as sunlight.

Age related macular degeneration (AMD) is again a very common condition which generally affects people over 60. In fact it is the leading cause of vision loss in older adults. It occurs when you get damage to the part of the eye called the 'macula'.

So what is the macula?

The macula is the part of your eye where the image of what you are looking at focuses onto. It is the most sensitive part of your retina and is made up of millions of light sensing cells. This is why when it is damaged the patient has quite a lot of difficulty because whatever he/she is trying to look at is blurry but everything around it is clear. This type of vision loss makes it difficult to recognise faces, drive a car, watch tv, read or do anything else which requires detailed vision.

However it also means that people will never go completely blind from just macular degeneration because they will still have peripheral vision or in other words, surrounding vision. Many people can function very well with just peripheral vision using various aids to help them around the house.

What are the risk factors?

Some common risk factors for AMD are-

-Advancing age
-Smoking has been shown to double the risk
-Race. Being caucasian can increase the risk of AMD compared to for example someone of African descent.
-Family history. You are more at risk if you have an immediate family member with AMD.

Conversely there are certain things you can do to minimise risk. These include-

-Give up smoking
-Maintaining normal blood pressure and cholesterol levels
-Eating a healthy well balanced diet. Or take vitamins specially designed for eye health.

Wet and dry AMD

There are two forms of AMD, wet and dry.

Dry is more common as is the cause for 90% of AMD. It happens when the cells in the macula slowly break down due to wear and tear and ageing. At the macula area the optician would see yellow deposits called drusen. There are no symptoms in the early stages but as the condition gets worse you will notice a blurred spot at the centre of your vision. Objects may appear less bright and you might need to increase the lighting in order to see. Unfortunately there is not much that can be done about dry AMD. Generally the condition is just monitored and advice given on how make the most of the remaining vision.

The second type is wet AMD. Wet AMD is a rarer but more severe type of condition compared to the dry type. This occurs when abnormal blood vessels behind the retina start to grow under the macula. These new blood vessels can be fragile and leak blood and fluid. The blood and fluid cause the macula to swell and damage occurs rapidly. The damage may also cause scarring of the retina.

Although loss of central vision can happen quickly, the hospital can slow down or stop the progression of wet AMD if it is detected before severe vision loss occurs.

What are the symptoms of wet AMD?

During the early stages of wet AMD straight lines may appear wavy. People with wet AMD also may develop a blind spot, which results in the loss of central vision.

If you notice these or other changes to your vision, contact us or your regular optician at once. Again, the doctor at the hospital may be able to treat the condition before severe vision loss occurs.

Treatment options for wet AMD

The therapies for wet AMD are not a guaranteed cure as the condition may progress even with treatment. However in a lot of cases they can be effective in stopping the progress and sometimes even improve the vision.
The two main types of treatment are injections and laser treatment.

- Injections. One option is to inject drugs into your eye. Don’t worry your eye would be numbed with anaesthetic so you wouldn’t feel any pain. The drugs aim to prevent new blood vessel growth in the eye which causes the wet AMD. If you get this treatment, you may need multiple injections.

- Photodynamic therapy. This technique involves laser treatment of select areas of the retina. First, a drug will be injected into a vein in your arm. The drug travels through the blood vessels in your body, including any new, abnormal blood vessels in your eye. The doctor then shines a laser beam into your eye to activate the drug in the unwanted blood vessels. Once activated, the drug destroys the new blood vessels and slows the rate of vision loss. This procedure takes about 20 minutes.

If there is moderate dry or wet AMD or advanced AMD in one eye then specific vitamins for the eyes may help reduce the progression to advanced AMD in either eye. You can get them off the shelf but it’s best to talk to your doctor before taking them. They wouldn’t improve AMD but in some instances they have been shown to slow the progression if you already have it.

Glaucoma is a group of diseases that damage the eye’s optic nerve and can result in vision loss and blindness. However, with early detection and treatment, you can often protect your eyes against serious vision loss. The optic nerve is a bundle of nerve fibres which connects your eye to your brain.

The optic nerve is often damaged due to high eye pressure. This is why when you go to the optician you have the test where they blow a puff of air into your eye. Although it’s not a pleasant test as it can make you jump, it is vital as if the pressure is high it indicates that the optic nerve may at risk of damage.

What causes high eye pressure?

The eye is filled with a clear fluid which nourishes the eye and helps it to keep its shape. This fluid constantly gets replaced, so as the eye produces new fluid the old fluid drains away. A common cause for high pressure is when the drain doesn’t allow the fluid to leave the eye fast enough. This means that the eye is producing fluid but not draining it away properly which means the pressure in the eye starts to go up slowly.

Just because the pressure in your eye is high doesn’t mean you will get glaucoma, although the risk is higher. Some people are more resistant to having eye pressure than others. If you are found to have high eye pressure the optician would refer you to the hospital for further checks and the eye doctor will decide if treatment is needed.

With this type of glaucoma there are no symptoms in the early stages so the only way to detect it is by having an eye test. If left untreated the vision can be permanently damaged.

In some rarer cases the drainage channel can close completely so no fluid can leave the eye. If this happens the pressure can increase very quickly resulting in severe pain and nausea, as well as redness of the eye and blurred vision. If you have these symptoms, you need to seek treatment immediately. This is a medical emergency. You must go to the nearest hospital or clinic. Without treatment to restore the flow of fluid, the eye can become blind. Usually, prompt laser surgery and medicines can clear the blockage, lower eye pressure, and protect vision.

What happens if glaucoma is left untreated?

If glaucoma is allowed to progress and get worse then eventually you will start to lose your peripheral vision. It’s a slow process which can take years however it is irreversible so once treatment starts it is about slowing its progress rather than improve the vision. This type of vision loss is the opposite to AMD because unless you have severe glaucoma you can still see what you are directly looking at but everything around it will be difficult to see, a bit like tunnel vision.

Who is at risk?

You are more at risk of glaucoma if you are

- African
- Have someone in the family with glaucoma
- If you are over 40

The optician generally checks for glaucoma in 3 different ways. They look at the optic disc at the back of the eye and check for changes in its appearance. They will check the pressure in the eye which is often done with a puff of air on your eye, however for home visits we use a machine that is a lot friendlier and won’t make you jump! Finally the peripheral vision is checked for blind spots which often occurs if the glaucoma is more advanced.

How is glaucoma treated?

If you are diagnosed with glaucoma at the hospital you will usually be given eye drops to reduce the pressure in your eye. This can often slow the progression of glaucoma if caught early enough which is why a regular eye test is essential. The drops are usually to be taken every day and the hospital will monitor the pressure at regular intervals to make sure they are doing a good job. There are many drops on the market so if one doesn’t work then there are others the doctor can try.

If the drops don’t reduce the pressure enough the doctor will consider surgery, normally using a laser, to create a hole in the eye for the fluid to drain through. This is usually an effective way of reducing the pressure in the eye.

Floaters are the little black dots or strands that literally float around in your eye. They are like debris and pigment within the liquid in your eye. Sometimes they can appear to look like a cobweb or dark shadows which follow your eye’s movement. People often describe them as seeing a fly in their vision. They are more noticeable against a bright background such as a white wall or a sunny sky. Not everyone has them but they are very common especially as you get older.

When you initially notice floaters in your vision it can be very annoying as you see them all the time. However the brain eventually learns to ignore them and after a while you stop paying attention to them. Because the floaters are in the liquid within the eye there is nowhere for them to go so unfortunately they will always remain there. Sometimes the big floaters can break up into smaller ones which can make it easier to ignore them.
In most cases having floaters is nothing to worry about. However sometimes floaters can be the result of a tear in your retina. If you notice a sudden increase in floaters, especially accompanied by flashes or light or peripheral vision loss then this could indicate a retinal detachment. A retinal detachment occurs when the retina is lifted from its normal position at the back wall of the eye.

If you suspect you have a retinal detachment then you need to go to A&E because if left untreated, it can lead to permanent vision damage within days or even blindness in the eye. At the hospital they would usually use a laser to seal the retina back to the wall of the eye.
What causes floaters?

Floaters occur when the vitreous, a gel-like substance that fills up the eye and helps it maintain a round shape, slowly shrinks. When it shrinks it can become stringy and this is what gives a cob web effect. Sometimes when the vitreous shrinks it pulls on the retina and dislodges pigment with it. The floaters that result from this effect are large and very obvious. It’s when the vitreous pulls on the retina too hard that a retinal detachment or tear can occur.

How are floaters treated?

In the vast majority of cases there is no treatment required. On rare occasions, floaters can be so dense that they significantly affect vision. In these cases a vitrectomy, a surgical procedure that removes floaters from the vitreous, may be needed.

A vitrectomy removes the vitreous gel, along with its floating debris, from the eye. The vitreous is replaced with a salt solution. This solution is clear so you your vision should go back to normal after the operation. However the operation carries significant risks because of possible complications, which include retinal detachment, retinal tears, and cataract. Most eye surgeons are reluctant to recommend this surgery unless the floaters seriously interfere with vision.