Eye Information

Here you will find a wealth of information relating to your eyes. Please select an option from the menu on the left and the information will appear below...

Common Eye Problems

Macular degeneration is the deterioration of the cells in the macula, a tiny area near the centre of the retina (lining of the eye) that is responsible for the most detailed vision.

The deterioration therefore affects your central vision that is used for reading, writing, watching television driving and recognizing faces. Macular degeneration causes progressive loss of central vision. Your peripheral vision is not affected.

What causes macular degeneration?

Damage to the retinal cells occurs from free radicals. Free radicals are caused by ultra-violet and blue light incident on the retina and also as natural products of metabolism. They cause oxidation and destabilization of the retinal cells.

Free radical damage is cumulative with age; therefore the incidence of macular degeneration increases with age, (hence the term AMD). Risk factors include:

  • Smoking increases the risk by up to 5 times.
  • Diabetes.
  • Uncontrolled high blood pressure
  • Poor diet or conditions causing difficulty-absorbing nutrients from the diet.
  • Certain types of medication.
  • Women are twice as likely to suffer from AMD
  • Excess exposure to UV

What are wet and dry AMD?

There are two types of AMD. The more common type is non-exudative AMD also known as dry AMD but this may be the precursor in 10 to 20% of patients to the more serious exudative or wet AMD in which new blood vessels begin to grow in the macula area, which may cause severe central visual loss.

What treatment is currently available for AMD?

There is no conventional medical treatment for dry AMD. Recent research has found that there can be a preventative and protective effect from using various micronutrients and vitamins in eye disease. The use of specific dietary components called carotenoids help the retina to protect and even repair itself in age related macular degeneration.

A Carotenoid called Lutein is known to protect the retina from blue light that causes free radicals and Lutein levels are higher in the retina of people without AMD than those suffering from the disease.

Pure Focus Spray is recommended for patients suffering from AMD. The sub-lingual (under the tongue) spray is absorbed by the mucus membranes of the mouth and allows good levels of Lutein in the blood system and therefore at the macula.

The Pure Focus spray is recommended for patients with macula disease. Supplements such as I Caps vitamin tablets which contain Lutein are useful for prevention in younger patients who are at risk of developing the problem, but not so effective in treatment of the disease.

What can happen to the vision with AMD?

In the very early stages you may not notice much change in the vision. You may notice it takes longer for you eyes to adjust to changes in illumination outdoors/indoors.

As AMD progresses you may notice

  • Words appear blurred and difficult to read
  • It may be difficult to recognize people across the road
  • There may be a blank or dark area blocking the centre of your vision (scotoma)
  • Colours may seem dim
  • Straight lines may seem wavy

The wet or proliferative type of AMD causes more severe symptoms and deteriorates more quickly and loss of vision can occur over a matter of a few weeks or months.

We recommend all patients regularly have our advanced retinal screening images taken. The system we use is a revolutionary retinal photography machine which enables the macula to be examined. It can show early macula changes before visual loss is apparent. This helps to detect patients who are at risk much earlier and initiate nutritional therapy.

Is there a hereditary component in AMD - what should I tell my children?

At the moment, our gene set is fixed: it is possible in the future that genes will be manipulated to avoid the tendency to certain disease.

In the meantime, if you have a family history of eye disease, you are more likely to get the same problems. Those at risk should alter their diet and lifestyle to reduce their exposure to some of the causative factors and reduce the likelihood of suffering the same problems.

Diet plays a key role in depositing the required Lutein at the macula and ensuring adequate Lutein is regarded as likely to help prevent AMD. Up to the age of 40, a good diet including the above is probably protection enough.

Anti-oxidants include vitamins A, C and E and attention to the diet to ensure healthy quantities of fresh fruit, and vegetables is advised as a preventative measure. Carotenoids particularly are found in green leafy vegetables with raw spinach being a particularly good source. Other useful vegetables are Brussel sprouts, broccoli, green beans and green peas, egg yolks and red, yellow and orange peppers.

If there is a family history of AMD, a multivitamin and mineral tablet containing vitamins A, C and E with zinc, selenium, manganese and copper may be usefully recommended as a preventative measure for the (non smoking) over 40s. I Caps are recommended as they have the necessary vitamins as well as Lutein and Zeaxanthin.. For smokers, an ACE vitamin supplement and sublingual (Pure Focus) Lutein is recommended because smoking is a major risk factor.

A cataract occurs when the normally transparent lens in your eye gradually becomes cloudy. The lens is responsible for focusing light onto the retina at the back of the eye, which in turn transmits the image to the brain. A cataract blurs the vision as the light is no longer clearly focused on the retina and vision gets worse, particularly for distant objects. It can become difficult to recognize people across the street, see television clearly or drive, particularly at night.

What causes Cataracts?

Most cataracts are slow growing and a natural consequence of the aging progress due to exposure to UV from the sun, smoking and poor nutrition. These risk factors increase the number of free radicals in the body. These free radicals disrupts the linkage of proteins in the lens of the eye. These proteins are arranged in a regular array in the healthy eye, allowing transparency. Cross linkage causes the proteins to clump together causing loss of transparency. This is like the white of an egg that is clear when raw, but once cooked the protein denatures and becomes opaque. About half of patients aged 65 to 75 have some degree of cataract and the incidence increases with age - it has been said that if we live long enough, all of us will get cataract to some degree. Most patients over the age of 80 have cataracts that affect their vision to some extent. Poor nutrition, smoking and UV radiation are all factors that hasten cataract formation because they increase the number of free radicals in the body. Cataracts can occur from other causes for example through head trauma, and certain metabolic illnesses such as diabetes. Rarely, cataracts are present at birth.

What are the symptoms of Cataract?

A cataract causes the vision to deteriorate fairly slowly, often in one eye more than the other although both eyes will almost always be affected eventually. Patients often complain of filmy vision, experience ghosting of their sight and sometimes double vision in the affected eye. The vision can vary day to day and in different lighting; bright sunlight can cause problems with glare, which may need tinted or photochromic lenses to help alleviate the problem. Conversely it is often difficult to read in dull illumination. Sometimes the developing cataract can make the spectacle prescription change as the lens becomes denser. In such cases, called nuclear cataract, the problem can often be managed for a significant time by adjusting the spectacles prescription on a regular basis.

Can I do anything to stop my cataracts getting worse?

There is evidence that UV damage is cumulative and therefore a high annual exposure to sunlight hastens cataract development. We therefore recommend that good sunglasses are worn. If you wear spectacles for distance vision driving or out of doors, prescription sunspectacles are recommended with a good UV blocking lens will help. Recent research has shown that the use of NAC (N-acetyl-carnosine) may help in combination with Pure Focus Lutein spray. Link to NAC How can my cataracts be treated? Early cataract management means ensuring that the spectacle prescription is accurate and increasing the light when reading or using magnifiers may help for a while. Self treatment with NAC (see above) may be beneficial. Cataract surgery should be considered if the reduced vision is affecting day to day life. There is no longer a need for the cataract to be ?ripe? before treatment. The surgical treatment is to remove the cloudy lens and replace it with a clear intraocular lens (IOL). This IOL needs no care and cannot be felt or seen once it is in place. It remains as a permanent part of the eye. Should cataracts occur in both eyes, they will not be treated at the same time, but one eye, usually the worse affected, will be operated on first. The other eye can then be treated a few months later. This is to minimise the chance of a post operative infection spreading from one eye to the other.

How long will I have to stay in hospital?

For most patients cataract removal is done under local anaesthetic as Day Case surgery which means no overnight stay in hospital. Your consultant ophthalmologist will discuss with you the best treatment in your particular case.

How long does the operation take?

Most patients are suitable for small incision (phacoemulsification) surgery which takes 20-30 minutes. For some patients, depending on the complexity of the operation and any other eye disease, it can be longer. What happens after the operation? The eye may be uncomfortable and possibly gritty but there is normally no severe pain. Normal analgesics (pain killers) are usually all that are needed for pain relief. The pupil will be dilated for the first 24hours and so dark spectacles will help with any light sensitivity. Vision may remain slightly blurred. Occasionally patients experience double vision until the local anaesthetic wears off. Normally the cataract is removed with such a small incision that a patient can return to normal day to day activities the next day, including reading, watching TV and light exercise ( walking etc) Strenuous exercise and heavy lifting should be avoided for 2-4 weeks.

When can I go back to work?

A clerical job may be resumed after 2-3 days. Manual work may be resumed after 2-4 weeks - your consultant will advise on specific jobs.

Is cataract surgery safe?

All surgical procedures carry an element of risk. Cataract surgery has a high success rate with over 90% of patients achieving a satisfactory outcome. The vision achieved will, of course depend on any other factors which are affect the health of the eye in a particular individual, for example co-existing age related macular degeneration (AMD) What are the possible complications of surgery? The possible complications of cataract surgery include: * Posterior capsule thickening (see below) * Post-operative infection * Haemorrhage in the eye * Clouding of the cornea * Swelling of the macula (back of the eye) * Retinal detachment Serious problems are uncommon and can mostly be treated successfully.

What is the most common complication of cataract surgery?

When a cataract is removed, the transparent capsular bag which supports the lens is left in place. In 15-20% of eyes, this capsular bag thickens and becomes less transparent and the vision begins to cloud over again. Some patients worry that the cataract is growing back. This cannot happen, and the capsule thickening can be treated by laser in an outpatient procedure. Posterior capsule thickening can occur usually within the first 2 years of surgery, often within 6-12 months. If you have any concerns about you vision in the months or years after surgery, consult the optometrist who referred you and they will be able to examine you for capsule thickening and refer for treatment.

How long after the operation must I wait until I can have my eyes tested and new spectacles prescribed?

After 3-4 weeks, as long as there have been no complications, you will be asked to see the optometrist (optician) who referred you for a follow up appointment. At this time, adjustments to your spectacle prescription can be made. Sometimes the vision has improved so much that only reading spectacles are required. I use bifocal/varifocal spectacles at the moment - will I still be able to do so after the operation? Yes, normally that is not a problem. Occasionally, patients have such a big difference in the prescription between the eyes that this is no longer possible, but the optometrist will tell you if that is likely to be a problem in your case.

The term colour deficient is usually used instead of the term colour blind, which implies that no colours can be seen. In colour deficiency, the perception of colour is altered because of an abnormality in the pigments in the retina (back of the eye)

What is colour vision deficiency?

The nerve cells which receive and process light at the back of the eye - the retina - are of two main types: rods which work in dull light and cones which allow us to see fine detail and colours by day. Three different chemicals can be found within the cone nerve cells, so that cone responds to red, green or blue light in a similar manner to colour television. Deficiency is caused by an abnormal cone pigment, usually the one which controls either red or green colours. Defective colour vision can range from near normal, where the chemical within the red or green cones is only slightly altered, to severe where the chemical is altered considerably or in the most severe cases, absent completely. In mild deficiency, only pale colours will be confused unless the lighting is poor or the person is tired or under pressure to make a quick decision of colour name when confusion of deeper hues may occur. Complete colour vision deficiency where all colours are seen as variations of black and white is extremely rare.

Why are more men than women colour deficient?

Defective colour vision may be inherited. A girl's colour vision may be normal, but she can carry the defective gene which can be passed to her children. There is a 50/50 chance a boy will be colour defective if his mother is a carrier of the defective gene, so brothers within the same family can be affected. A girl can only inherit defective colour vision if her father has the problem and her mother is a carrier or herself colour deficient.

Will inherited colour deficiency change with age?

No. The inherited alterations to Colour vision involve both eyes and remain stable through life.

Can you develop colour deficiency?

Yes. Some diseases can cause a colour deficiency, often only in one eye. These include diabetes, multiple sclerosis and cardiovascular diseases (including high blood pressure), some liver diseases and many eye diseases. The colour deficiency is caused by damage to the nerves supplying the cones or the nerve pathways from them to the brain. In these cases, colour vision may be temporarily or permanently altered. Colour discrimination can be affected on its own or may be noticed with other visual problems, such as overall blurring of near or distance vision, or gaps in the field of vision. Women and men are equally at risk. Drugs prescribed for arthritis, malaria, depression and heart disease can, on occasion, significantly impair colour vision. Viagra commonly changes colour vision temporarily, often objects acquiring a blue tint. This is temporary. Long-term use of aspirin has been implicated in colour perception change and tobacco and alcohol taken in excess can have similar effects. Many industrial chemicals can permanently alter our appreciation of colours. Glaucoma, cataract and most eye problems affecting the retina or nerve pathways to the brain can give gradually worsening problems with many different colours, including blues and greens. Since colour vision changes can be an early sign of disease or a side effect of prescribed medication, it is important that you consult your optician or GP if you are aware that your appreciation of colours is changing.

How does colour vision affect normal life?

Some careers do involve some degree of colour identification. Normal colour vision is required to be a pilot or train driver, and companies involved in printing, textiles, paints and electronic components screen prospective employees and may refuse entry for certain jobs if colour perception is not normal. The armed services require normal colour vision for some jobs. The police require a normal colour vision test on application. A colour deficient individual is allowed to drive although there are a few reported cases of accidents caused by people with faulty colour perception driving through a red traffic light. In some countries, law prohibits colour defective people from driving commercial vehicles. It is always sensible to inform teachers if a child is known to have difficulty in identifying colours as colour coding is common.

Can anything be done to correct colour deficiency?

Nothing can replace a faulty mechanism in the retina of the eye - which is essentially a part of the brain - many colour defective people do learn ways of compensating for their difficulty - and indeed are often unaware that they don't see the world in the same way as others, as it has always been that way for them. Good light can help. There is no permanent way of restoring the lost sensation or appreciation of colour, although recent studies have shown some special tinted contact lenses and spectacles can improve colour discrimination when worn.

How is colour vision tested?

Easy tests for defective colour vision are used in the optician's consulting room. These involve reading coloured numbers from a book or following a trail of dots for young children. Some employers require a signal light test (naming of the light colours in order). Optometrists can give such a test as part of an eye examination. Some school medical examinations may include colour vision tests. If a detailed evaluation of colour vision is required, the hospital optometrists have a wider selection of tests available.

I think my child may have a colour vision problem. What should I do?

Book an appointment for an eye examination that includes a test for colour vision. The optometrist will be happy to answer any questions you may have.

Floaters are the dark spots or wavy lines which appear in your vision particularly if you look at a white wall or blue sky. They move with your eye, sometime patients say like a spider in the vision, but lag slightly behind the eye movement.

Are they anything to be concerned about?

Most people have a few floaters, particularly if you are short-sighted, and they tend to increase as you get older. If there is any sudden change in the appearance of the floaters, especially if they are associated with flashes of light, this needs investigation immediately to differentiate between posterior vitreous detachment (which is common in the over 60s and not sight threatening) and retinal detachment.

What is Posterior Vitreous Detachment (PVD)?

PVD occurs most commonly in the over 60s as the vitreous jelly in the eye condenses slightly and separates fractionally from the underlying retina, accompanied by a sudden increase in floaters and sometimes flashes of light. PVD is common and in most cases perfectly harmless. Statistically in the 6 weeks after a PVD you are considered to be at higher risk of a retinal detachment.

What is a Retinal Detachment?

The retina is the very thin lining of the back of the eye which receives images and then sends the information along the optic nerve to the brain. This tissue is very thin and may tear or break. The tear then becomes worse and floaters appear in the vision often like a cobweb. As the retina peels off in a detachment, people say it?s like a veil or curtain coming down over their vision.

What causes the flashes of light?

In both PVD and retinal detachment, flashes of light occur when the vitreous jelly pulls on the retina at the points where it is attached. The nerve receptors are stimulated by this traction (pulling) and fire off a message to the brain. The brain interprets this as a flash of light.

Is Retinal Detachment serious?

Yes, very. The retina receives its nourishment from the underlying tissues of the eye and, when detached from the blood supply is starved of oxygen and quickly dies. A detached retina needs to be reattached very quickly to prevent blindness in the detached area.

What should I do if I get a sudden onset of floaters and flashes of light?

Seek immediate help from an eyecare professional, if necessary go directly to Accident and Emergency as it is vital that your eyes are checked as soon as possible.

How can Retinal Detachment be treated?

Treatment is by an ophthalmologist using a very special ophthalmic laser to weld the retina back. The sooner repair occurs the better chance of retaining useful vision.

Are certain people more at risk of Retinal Detachment?

Yes, causes of retinal detachment include trauma (road traffic accidents, bungee jumping, boxing) and certain eye conditions predispose people to detachment including people who are very short-sighted and who have had operations on their eye such as cataract removal.

I am very short-sighted - how can I tell if I am at particular risk?

We recommend all patients have a retinal examination which can show any problems with the peripheral retinal such as small breaks and tears before detachment occurs. In such cases, referral for preventative laser is advised.