age-related macular degeneration

Age-related macular degeneration (AMD) is an eye condition that affects a tiny part of the retina at the back of your eye, which is called the macula.

AMD causes problems with your central vision, but does not lead to total loss of sight and is not painful. AMD affects the vision you use when you're looking directly at something, for example when you're reading, looking at photos or watching television. AMD may make this central vision distorted or blurry and, over a period of time, it may cause a blank patch in the centre of your vision.

Causes

At the moment, the exact cause for AMD is not known. Some things are thought to increase your chances of developing AMD:

• Age: AMD develops as people grow older and is most often seen in people over the age of 65, although it can develop in people who are in their forties and fifties
• Gender: more women have AMD than men, probably because women tend to live longer than men.
• Genes: some genes have been identified which seem to be linked to the development of AMD in some people. This has been discovered by looking at families with more than one member who has AMD, but not all AMD is thought to be inherited
• Smoking: smoking greatly increases your risk of developing AMD. Studies also show that stopping smoking can reduce your risk of developing AMD
• Sunlight: some studies suggest that exposure to high levels of sunlight (particularly the UV light contained in sunlight) throughout your life may increase your risk of developing AMD. Wearing sunglasses to protect your eyes from the UV light in sunlight is a good idea for everyone throughout their life
• What you eat: a number of studies have looked at diet as a risk factor for someone developing AMD. At the moment there isn't agreement on how much of a risk factor diet is. There is some evidence that vitamins A, C and E and zinc may help to slow the progression of AMD in people who already have the condition.

Although you cannot change your age or genes, current thinking is that protecting your eyes from the sun, eating a balanced diet with plenty of fresh fruit and vegetables, and stopping smoking may all help to keep your eyes as healthy as possible.
Unfortunately, because the exact cause of AMD is not known you may develop this condition even if you don't have any of these risk factors.

Symptoms

Symptoms vary from person to person, but usually the first problems people notice are with their ability to see detail. You may have problems reading small print, even if you wear your usual reading glasses, or you may find that there is a slight smudge in your sight or that your vision has a small blurred area in the centre. Straight lines may look distorted or wavy or as if there's a little bump in them. You may also find you become sensitive to bright light or that you see shapes and lights that aren't actually there. Sometimes people may only notice these changes in one eye.
You should have your eyes tested by an optometrist (optician) if:

• you notice any difficulty with reading small print with your reading glasses
• straight lines start to look wavy or distorted
• your vision isn't as clear as it used to be.

The optometrist will be able to measure any changes in your vision and examine the back of your eye. If they detect any changes to your macula or any cause for concern they will arrange an appointment with the ophthalmologist (hospital eye consultant) for further tests.

The macula

AMD affects the macula area of the retina. The macula is a tiny area of your retina which is very important for seeing detail, colour and things directly in front of you.


When the light enters your eye it is focused onto your retina at the back of your eye. The retina includes a number of layers but the most important for vision is a layer made up of cells called photoreceptors. Photoreceptors are cells which are sensitive to light.
The macula, which is about the size of a pinhead, is a specialised area of the retina that contains a few million specialised photoreceptor cells called cone cells. These cone cells function best in bright light levels and allow you to see fine detail for activities such as reading and writing and to recognise colours.
Away from the central macula is the peripheral retina, composed mostly of the other type of photoreceptor called rod cells. They enable us to see when light is dim and provide peripheral (side) vision outside of the main line of sight. Peripheral vision is the sight you have out of the corner of your eye when looking straight ahead.
When someone develops AMD, the cone cells in the macula area become damaged and stop working as well as they should.

Types of AMD

There are two main types of AMD - "wet" AMD and "dry" AMD. They are called "wet" and "dry" because of what happens inside your eye and what the ophthalmologist (hospital eye doctor) sees when examining the inside of your eye, not because of how the eye feels or whether you have a watery or dry eye.

Dry AMD

Dry AMD is the more common type of AMD. It usually develops very slowly and causes a gradual change in your central vision. Dry AMD usually takes a long time, maybe a number of years to get to its final stage. At its worst, dry AMD causes a blank patch in the centre of your vision in both of your eyes. But it doesn't affect your peripheral vision, so never leads to total blindness.

Wet AMD

About 10-15 per cent of people who develop AMD have wet AMD. You develop wet AMD when the cells of the macula stop working correctly and the body starts growing new blood vessels to fix the problem. Unfortunately, these blood vessels grow in the wrong place and cause swelling and bleeding underneath the macula. This new blood vessel growth, medically known as neo-vascularisation, causes more damage to your macula and eventually leads to scarring. Both the new blood vessels and the scarring damages your central vision and may lead to a blank patch in the centre of your sight.
Wet AMD can develop very quickly, making serious changes to your central vision in a short period of time. Treatment is now available for wet AMD, which stops the new blood vessels from growing and damaging your macula. This treatment usually needs to be given quickly before the new blood vessels do too much damage to your macula. If the blood vessels are left to grow, the scarring and the sight loss it causes is usually permanent. Wet AMD doesn't affect your peripheral vision, so it doesn't lead to total blindness.

Both types of AMD

Wet and dry AMD have things in common. They usually affect both your eyes, though sometimes one eye may be affected long before the other. Both wet and dry AMD only affect your central vision and won't affect your vision around the edge of your sight. So neither type of AMD will cause you to lose all your sight.
Some people diagnosed with dry AMD find that, with time, new blood vessels grow and they develop wet AMD. If you have dry AMD and your sight suddenly changes you should always have this checked by your ophthalmologist (hospital eye doctor).
Some people may have wet AMD in one eye and have dry AMD in the other which doesn't develop into wet AMD. Most people, however, have the same type of AMD in both eyes.
Confusingly, people who have had wet AMD for a long time, causing bad scarring on their retina, may be told that their wet AMD has "dried up". This usually means that there are no new blood vessels growing and that your macula has been badly scarred. At this stage of wet AMD, the treatments available wouldn't help.
AMD is not painful and it never leads to a complete loss of vision. Most people with AMD keep their peripheral vision (everything around the edge). This peripheral vision will mean that you should still be able to get around on your own and make use of this vision everyday.

Changes in your vision

If you notice a sudden change in your vision, you should always have your eyes examined by an eye health professional. Usually this is an optometrist in the high street. However, if your sight changes very quickly then you can attend the accident and emergency department at your nearest hospital, where an ophthalmologist will be able to check your eyes.
If you have slight changes in your vision then you should arrange for an eye test with an optometrist (optician). They are trained to detect any eye problems and, if necessary, can refer you to your GP for a further appointment with the ophthalmologist at the hospital.
If you have dry AMD and you notice a sudden change in either of your eyes you should let the hospital know. This is because dry type AMD can develop into wet AMD and if this happens sight saving treatment may be possible.
If you have AMD in one eye and you notice a sudden change in either eye you should let the hospital know as soon as possible. This is because you can have different types of AMD in each eye and treatment might now be of help to you.

Hospital eye examination

To find out whether you have AMD and what type of AMD you have, the ophthalmologist will have to perform a number of tests.
At the hospital, your vision will be checked and your pupils dilated to allow the ophthalmologist to look at the macula. Your pupils are dilated with drops that take about 30 minutes to work. They will make you sensitive to light and cause your vision to be blurry. The drops allow the ophthalmologist to see the inside of your eye more easily. The effects of the drop usually wear off in about six hours though sometimes it can happen overnight. It is not safe to drive until the affects have worn off.
The ophthalmologist looks at the inside of your eye using a special microscope called a slit lamp. You place your chin on a rest and the ophthalmologist sits opposite you. The ophthalmologist will ask you to look in particular directions while shining a light into your eye. This allows them to see your retina and any changes that AMD may have caused. Although very bright, the light cannot damage your eye.
Sometimes the ophthalmologist can tell you whether they think you have AMD or not from this examination. However, you may need a test called a Fluorescein angiogram to find out for certain if you have AMD or to find out whether you have wet or dry AMD.

Fluorescein angiogram

This test helps the ophthalmologist find out more about your AMD and whether you have wet or dry AMD. Usually the network of blood vessels underneath your retina can't be seen by examining your eyes with a slit lamp. The ophthalmologist can see the damage to your retina but they can't see the detail of the blood vessels this way. A Fluorescein angiogram is a way of taking pictures of these blood vessels which allows the ophthalmologist to see if there are any changes which could be causing problems.
Before a series of pictures is taken, a yellow dye is injected into your arm which then travels through your bloodstream to your eye. This usually isn't painful but can make some people feel sick. This dye makes the blood vessels visible on the pictures taken.
Once the dye has been injected you will be asked to look at a special machine. The machine takes pictures of the back of your eye as the dye is travelling through the blood vessels. You'll experience a series of flashing lights as the pictures are taken, but the test isn't painful. It usually takes about 10minutes.
It is a very common test and very few people have any serious side effects. The injection may give your skin a slight yellow tinge from the dye and it soon passes into your urine, which may also appear a darker yellow than normal (possibly for up to two to three days) but often it fades quicker than that. Some people are dazzled for a while after the flashing lights but most people find the test straightforward.
These tests help the ophthalmologist decide which type of AMD you have and if any treatment is possible.

Treatment

A number of treatments are available for wet AMD. These mainly work by stopping the growth of new blood vessels. This means that treatments usually need to be given fairly quickly once the blood vessels start to grow in your eye. If the blood vessels are allowed to grow for too long the blood vessels may scar the retina and this scarring cannot be treated.
At the moment there is no treatment for dry AMD. This is because dry AMD doesn't involve new blood vessels growing. Although research is continuing to find a treatment for dry AMD, nothing is available yet.

Treatments for wet AMD - Anti-VEGF treatment

The most recent treatment available on the NHS for wet AMD is with an anti-vascular endothelial growth factor (anti-VEGF) drug, called Lucentis. As new blood vessels form in your eye, your body produces a chemical which stimulates further new blood vessel growth. Anti-VEGF drugs interfere with these chemicals and stop the vessels from growing. By stopping blood vessels growing and leaking, further damage to your sight is prevented.

Lucentis has to be injected into your eye. This is called an intravitreal injection. This injection needs to be given in an operating theatre or a "clean room" to avoid infection. A clean room is a sterile room which may not have the full facilities of an operating theatre.
Before the injection, you will be given anaesthetic eye drops to make your eye numb, an antibiotic drop to help prevent you getting an infection and a drop to dilate your pupil.
The injection shouldn't be painful but your eye may be a little sore after the anaesthetic wears off. Because the injection goes into the gel in the centre of your eye there is a slight chance that the pressure inside your eye may rise a little. This shouldn't cause you any pain or change your vision, but will need to be checked shortly after you have the injection.
The sight in the treated eye may be blurry because of the drop to dilate your pupil, but this should wear off within a day. Some people find that they have slight swirls in their vision for a few days after the injection. You may find that your eye waters a bit more following the injection and that your eye may be slightly red or irritated but this normally gets better after a few days. If your eye becomes very painful or very red and hot to touch or you notice any worsening of your vision you should let your hospital know as soon as possible.
The main complications of this treatment are the chance of a rise in pressure in your eye, retinal detachment and eye infections. These only happen to a very small minority of people (less than one per cent of people having the treatment) and there are treatments available if any of these complications happen to you.
Usually you will need more than one injection of Lucentis. Normally, a course of three monthly injections is given to start with and then you should be monitored every four weeks to check that the treatment is working. Many people go on to have more injections after these initial three.
Usually anti-VEGF treatments have a high success rate and in most people they stop sight getting worse. About 40 per cent of people also see an improvement in their vision.

Photodynamic therapy

Anti-VEGF treatments are usually the first treatment offered to people with wet AMD. However, sometimes it may be necessary to try a different treatment called Photodynamic therapy (PDT). This is a type of laser treatment which uses a combination of a light sensitive drug and a low energy (cold) laser to stop new blood vessels growing.
You will be given an injection, usually in your arm, of a light sensitive drug called Verteporfin. Once this drug has made its way to the new blood vessels which grow in wet AMD, your ophthalmologist can target a very bright light (a cold laser) onto these blood vessels. The laser causes a reaction with the drug which seals off any new blood vessels that may be growing.
This treatment also needs to be given at the early stages of the blood vessel growth so that it can prevent the new blood vessels causing damage.

Treating dry AMD

Unfortunately at the moment there is no way to treat dry AMD. Although research is going on to try and find out why the cells of the macula stop working, this hasn't yet lead to a treatment.
There is some evidence that high doses of vitamin A, C, E and the minerals zinc and copper when taken together may help slow down the progression of dry AMD, particularly if someone already has changes to their vision because of AMD in one eye.
There are a number of vitamin products available which have been designed for people with dry AMD and you can usually buy these over the counter from your pharmacist. However, there is no evidence that taking high doses of these vitamins can prevent you developing AMD in the first place. A balanced diet with plenty of fresh fruit and vegetables is good for your general health and may also help your eye health.

Coping

Being diagnosed with an eye condition can be very upsetting. You may find that you are worried about the future and how you will manage with a change in your vision. All these feelings are natural.
Some people may want to talk over some of these feelings with someone outside their circle of friends or family. RNIB can help, with our telephone Helpline and our emotional support service. Your GP or social worker may also be able to help you find a counsellor if you think this would help you.
The Macular Disease Society has local groups which meet throughout the country and also offer a telephone counselling service. Sometimes it can help to talk about your feelings or share with people who may have had similar experiences.

Help to see things better

Both types of AMD can cause severe problems with your central vision. However, most people with AMD have some vision that they can use everyday and using your vision won't make your AMD worse.
There are lots of things that you can do to make the most of the vision you have. This may mean making things bigger, using brighter lighting or using colour to make things easier to see. Ask your ophthalmologist, optician or GP to refer you to your local low vision service, which can provide you with magnifiers to help with reading, advice on lighting and tips on how to make the most of your peripheral vision for everyday tasks to help make the most of your sight.
Local social services should also be able to offer you information on staying safe in your home and getting out and about safely. They should also be able to offer you some practical mobility training to give you more confidence when you are out.
Our Helpline can also give you information about the low vision services available, and our website offers lots of practical information about adapting to changes in your vision and products that make everyday tasks easier.

What next

Useful contacts

Macular Disease Society
PO Box 1870, Andover SP10 9AD
Tel: 0845 241 2041
help@maculardisease.org
Royal College of Ophthalmologists
17 Cornwall Terrace, London NW1 4QW
Tel: 020 7935 0702
Driver and Vehicle Licensing Agency (DVLA)
Drivers Customer Services (DCS)
Correspondence Team DVLA
Swansea SA6 7JL
Tel: 0300 790 6801

We value your feedback

We would be interested to know if you found there was any information that was missing, or if there is anything else you would like to tell us about the publication. If you would like to give us feedback, please call us on 020 7391 2006 or email us at publishing@rnib.org.uk
This information has been produced jointly by the Royal College of Ophthalmologists and Royal National Institute of Blind People, a certified member of the Information Standard.

© RNIB and RCOphth September 2010

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Posted in Eye health

Esotropia

Esotropia is the most common form of strabismus in infants, a condition that refers to any misalignment of the eyes. In the case of esotropia, one eye deviates inward toward the nose while the other fixates normally. Exotropia is the condition where one eye deviates outward, away from the nose. Strabismus, also called "cross-eye," occurs in about four percent of all children in the United States. It happens equally in males and females and is sometimes hereditary. Esotropia can also affect teenagers and adults, and it is usually related to systemic conditions such as high blood pressure, diabetes, strokes, or brain injuries.
The brain's ability to see three-dimensional objects depends on proper alignment of the eyes. When both eyes are properly aligned and aimed at the same target, the visual portion of the brain fuses the forms into a single image. When one eye turns inward, outward, upward, or downward, two different pictures are sent to the brain. This causes loss of depth perception and binocular vision.

When does esotropia occur?

• Pseudoesotropia (false esotropia) is actually the physical appearance of cross-eye when the eyes are perfectly aligned. Infants and young children often have a wide, flat nose with a fold of skin at the inner eyelid that makes the eyes appear crossed. This appearance usually disappears as the child grows.
• Congenital or infant esotropia can be present at birth or may develop anytime during the first 6 months of life. Although it is common for an infant's eyes to be intermittently misaligned, if the condition persists beyond the first few months, it should be checked by a physician. One to 2 percent of children have congenital esotropia, and the condition usually does not improve with age. Surgical correction is usually recommended between 6 and 14 months of age.
• Accommodative esotropia is a common form that occurs in farsighted children, usually 2 years old or older. Young children can often overcome farsightedness by focusing their eyes to adjust to the condition, but the effort required for this focusing causes the eyes to cross. Eyeglasses can reduce the focusing effort and sometimes straighten the eyes. In addition, special eyedrops, ointments, and lenses called prisms may also be effective. Eye exercises can also be helpful, especially in older children. Sometimes bifocals can correct the excessive turning in of the eyes for close work.
• Acquired esotropia occurs after infancy. Children who have been farsighted and have not had glasses, or children who were responsive to glasses but later developed an additional eye-crossing, are the most commonly affected. Children with acquired eye-crossing require prompt evaluation and treatment to correct the deviation and to restore binocular vision.

The causes of some forms of esotropia are not fully understood. There are six muscles that control eye movement, four that move it up and down and two that move it side to side. All these muscles must be coordinated and working properly in order for the brain to see a single image. When one or more of these muscles doesn't work properly, some form of strabismus may occur. Strabismus is more common in children with disorders that affect the brain such as cerebral palsy, Down syndrome, hydrocephalus, and brain tumors.

What are the symptoms of esotropia?

Symptoms of esotropia are decreased vision, double vision, and misaligned eyes. Children with esotropia do not use their eyes together and often squint in bright sunlight or tilt their heads in a specific direction to use their eyes together. They may also rub their eyes frequently. Children rarely tell you they are experiencing double vision, although they may close one eye to compensate for the problem. You may also notice signs of faulty depth perception.
When a young child has strabismus, the child's brain may learn to ignore the misaligned eye's image and see only the image from the best-seeing eye. This is called amblyopia, or lazy eye, and results in a loss of depth perception. In adults who develop strabismus, double vision sometimes occurs because the brain has already been trained to receive images from both eyes and cannot ignore the image from the turned eye.

What are the cures for esotropia?

Treatment depends on the type of esotropia. Accommodative esotropia can be treated successfully by correcting a refractive error with glasses, patching to force the use of the less-preferred eye, or other forms of therapy. Congenital and acquired esotropia usually require surgery for proper and permanent correction.
The surgeon makes a small incision in the tissue covering the eye in order to reach the eye muscles. Then either tight inner muscles are placed farther back to weaken their pull, or the loose outer muscles are tightened by shortening their length to allow the eye to move outward. The procedure is usually done under general anesthesia. Recovery time is rapid, and normal activities can usually be resumed within a few days. Following surgery, corrective eyeglasses may be needed and, in some cases, further surgery is required later to keep the eyes straight.

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Posted in Eye health

Cataract

What is a cataract?


A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Cataracts are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery.
A cataract can occur in either or both eyes. It cannot spread from one eye to the other.

What is the lens?

The lens is a clear part of the eye that helps to focus light, or an image, on the retina. The retina is the light-sensitive tissue at the back of the eye.
In a normal eye, light passes through the transparent lens to the retina. Once it reaches the retina, light is changed into nerve signals that are sent to the brain.
The lens must be clear for the retina to receive a sharp image. If the lens is cloudy from a cataract, the image you see will be blurred.

Are there other types of cataract?

Yes. Although most cataracts are related to aging, there are other types of cataract:

1. Secondary cataract. Cataracts can form after surgery for other eye problems, such as glaucoma. Cataracts also can develop in people who have other health problems, such as diabetes. Cataracts are sometimes linked to steroid use.
2. Traumatic cataract. Cataracts can develop after an eye injury, sometimes years later.
3. Congenital cataract. Some babies are born with cataracts or develop them in childhood, often in both eyes. These cataracts may be so small that they do not affect vision. If they do, the lenses may need to be removed.
4. Radiation cataract. Cataracts can develop after exposure to some types of radiation.

Causes and Risk Factors

What causes cataracts?

The lens lies behind the iris and the pupil. It works much like a camera lens. It focuses light onto the retina at the back of the eye, where an image is recorded. The lens also adjusts the eye's focus, letting us see things clearly both up close and far away. The lens is made of mostly water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it.
But as we age, some of the protein may clump together and start to cloud a small area of the lens. This is a cataract. Over time, the cataract may grow larger and cloud more of the lens, making it harder to see.
Researchers suspect that there are several causes of cataract, such as smoking and diabetes. Or, it may be that the protein in the lens just changes from the wear and tear it takes over the years.

How can cataracts affect my vision?

Age-related cataracts can affect your vision in two ways:

1. Clumps of protein reduce the sharpness of the image reaching the retina.
   The lens consists mostly of water and protein. When the protein clumps up, it clouds the lens and reduces the light that reaches the retina. The clouding may become severe enough to cause blurred vision. Most age-related cataracts develop from protein clumpings.
   When a cataract is small, the cloudiness affects only a small part of the lens. You may not notice any changes in your vision. Cataracts tend to "grow" slowly, so vision gets worse gradually. Over time, the cloudy area in the lens may get larger, and the cataract may increase in size. Seeing may become more difficult. Your vision may get duller or blurrier.
2. The clear lens slowly changes to a yellowish/brownish color, adding a brownish tint to vision.
   As the clear lens slowly colors with age, your vision gradually may acquire a brownish shade. At first, the amount of tinting may be small and may not cause a vision problem. Over time, increased tinting may make it more difficult to read and perform other routine activities. This gradual change in the amount of tinting does not affect the sharpness of the image transmitted to the retina.
   If you have advanced lens discoloration, you may not be able to identify blues and purples. You may be wearing what you believe to be a pair of black socks, only to find out from friends that you are wearing purple socks.

When are you most likely to have a cataract?

The term "age-related" is a little misleading. You don't have to be a senior citizen to get this type of cataract. In fact, people can have an age-related cataract in their 40s and 50s. But during middle age, most cataracts are small and do not affect vision. It is after age 60 that most cataracts steal vision.

Who is at risk for cataract?

The risk of cataract increases as you get older. Other risk factors for cataract include:

• Certain diseases such as diabetes.
• Personal behavior such as smoking and alcohol use.
• The environment such as prolonged exposure to sunlight.

What can I do to protect my vision?

Wearing sunglasses and a hat with a brim to block ultraviolet sunlight may help to delay cataract. If you smoke, stop. Researchers also believe good nutrition can help reduce the risk of age-related cataract. They recommend eating green leafy vegetables, fruit, and other foods with antioxidants.
If you are age 60 or older, you should have a comprehensive dilated eye exam at least once every two years. In addition to cataract, your eye care professional can check for signs of age-related macular degeneration, glaucoma, and other vision disorders. Early treatment for many eye diseases may save your sight.

Symptoms and Detection

What are the symptoms of a cataract?

The most common symptoms of a cataract are:

• 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. (This symptom may clear as the cataract gets larger.)
• Frequent prescription changes in your eyeglasses or contact lenses.
• These symptoms also can be a sign of other eye problems. If you have any of these symptoms, check with your eye care professional.

How is a cataract detected?

Cataract is detected through a comprehensive eye exam that includes:

1. Visual acuity test. This eye chart test measures how well you see at various distances.
2. Dilated eye exam. Drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
3. Tonometry. An instrument measures the pressure inside the eye. Numbing drops may be applied to your eye for this test.

Your eye care professional also may do other tests to learn more about the structure and health of your eye.

Treatment

How is a cataract treated?

The symptoms of early cataract may be improved with new eyeglasses, brighter lighting, anti-glare sunglasses, or magnifying lenses. If these measures do not help, surgery is the only effective treatment. Surgery involves removing the cloudy lens and replacing it with an artificial lens.
A cataract needs to be removed only when vision loss interferes with your everyday activities, such as driving, reading, or watching TV. You and your eye care professional can make this decision together. Once you understand the benefits and risks of surgery, you can make an informed decision about whether cataract surgery is right for you. In most cases, delaying cataract surgery will not cause long-term damage to your eye or make the surgery more difficult. You do not have to rush into surgery.
Sometimes a cataract should be removed even if it does not cause problems with your vision. For example, a cataract should be removed if it prevents examination or treatment of another eye problem, such as age-related macular degeneration or diabetic retinopathy. If your eye care professional finds a cataract, you may not need cataract surgery for several years. In fact, you might never need cataract surgery. By having your vision tested regularly, you and your eye care professional can discuss if and when you might need treatment.
If you choose surgery, your eye care professional may refer you to a specialist to remove the cataract.
If you have cataracts in both eyes that require surgery, the surgery will be performed on each eye at separate times, usually four to eight weeks apart.
Many people who need cataract surgery also have other eye conditions, such as age-related macular degeneration or glaucoma. If you have other eye conditions in addition to cataract, talk with your doctor. Learn about the risks, benefits, alternatives, and expected results of cataract surgery.

What are the different types of cataract surgery?

There are two types of cataract surgery. Your doctor can explain the differences and help determine which is better for you:

1. Phacoemulsification, or phaco. A small incision is made on the side of the cornea, the clear, dome-shaped surface that covers the front of the eye. Your doctor inserts a tiny probe into the eye. This device emits ultrasound waves that soften and break up the lens so that it can be removed by suction. Most cataract surgery today is done by phacoemulsification, also called "small incision cataract surgery."
2. Extracapsular surgery. Your doctor makes a longer incision on the side of the cornea and removes the cloudy core of the lens in one piece. The rest of the lens is removed by suction.

After the natural lens has been removed, it often is replaced by an artificial lens, called an intraocular lens (IOL). An IOL is a clear, plastic lens that requires no care and becomes a permanent part of your eye. Light is focused clearly by the IOL onto the retina, improving your vision. You will not feel or see the new lens.
Some people cannot have an IOL. They may have another eye disease or have problems during surgery. For these patients, a soft contact lens, or glasses that provide high magnification, may be suggested.

What are the risks of cataract surgery?

As with any surgery, cataract surgery poses risks, such as infection and bleeding. Before cataract surgery, your doctor may ask you to temporarily stop taking certain medications that increase the risk of bleeding during surgery. After surgery, you must keep your eye clean, wash your hands before touching your eye, and use the prescribed medications to help minimize the risk of infection. Serious infection can result in loss of vision.
Cataract surgery slightly increases your risk of retinal detachment. Other eye disorders, such as high myopia (nearsightedness), can further increase your risk of retinal detachment after cataract surgery. One sign of a retinal detachment is a sudden increase in flashes or floaters. Floaters are little "cobwebs" or specks that seem to float about in your field of vision. If you notice a sudden increase in floaters or flashes, see an eye care professional immediately. A retinal detachment is a medical emergency. If necessary, go to an emergency service or hospital. Your eye must be examined by an eye surgeon as soon as possible. A retinal detachment causes no pain. Early treatment for retinal detachment often can prevent permanent loss of vision. The sooner you get treatment, the more likely you will regain good vision. Even if you are treated promptly, some vision may be lost.
Talk to your eye care professional about these risks. Make sure cataract surgery is right for you.

Is cataract surgery effective?

Cataract removal is one of the most common operations performed in the United States. It also is one of the safest and most effective types of surgery. In about 90 percent of cases, people who have cataract surgery have better vision afterward.

What happens before surgery?

A week or two before surgery, your doctor will do some tests. These tests may include measuring the curve of the cornea and the size and shape of your eye. This information helps your doctor choose the right type of IOL.
You may be asked not to eat or drink anything 12 hours before your surgery.

What happens during surgery?

At the hospital or eye clinic, drops will be put into your eye to dilate the pupil. The area around your eye will be washed and cleansed.
The operation usually lasts less than one hour and is almost painless. Many people choose to stay awake during surgery. Others may need to be put to sleep for a short time.
If you are awake, you will have an anesthetic to numb the nerves in and around your eye.
After the operation, a patch may be placed over your eye. You will rest for a while. Your medical team will watch for any problems, such as bleeding. Most people who have cataract surgery can go home the same day. You will need someone to drive you home.

What happens after surgery?

Itching and mild discomfort are normal after cataract surgery. Some fluid discharge is also common. Your eye may be sensitive to light and touch. If you have discomfort, your doctor can suggest treatment. After one or two days, moderate discomfort should disappear.
For a few days after surgery, your doctor may ask you to use eyedrops to help healing and decrease the risk of infection. Ask your doctor about how to use your eyedrops, how often to use them, and what effects they can have. You will need to wear an eye shield or eyeglasses to help protect your eye. Avoid rubbing or pressing on your eye.
When you are home, try not to bend from the waist to pick up objects on the floor. Do not lift any heavy objects. You can walk, climb stairs, and do light household chores.
In most cases, healing will be complete within eight weeks. Your doctor will schedule exams to check on your progress.

Can problems develop after surgery?

Problems after surgery are rare, but they can occur. These problems can include infection, bleeding, inflammation (pain, redness, swelling), loss of vision, double vision, and high or low eye pressure. With prompt medical attention, these problems can usually be treated successfully.
Sometimes the eye tissue that encloses the IOL becomes cloudy and may blur your vision. This condition is called an after-cataract. An after-cataract can develop months or years after cataract surgery.
An after-cataract is treated with a laser. Your doctor uses a laser to make a tiny hole in the eye tissue behind the lens to let light pass through. This outpatient procedure is called a YAG laser capsulotomy. It is painless and rarely results in increased eye pressure or other eye problems. As a precaution, your doctor may give you eyedrops to lower your eye pressure before or after the procedure.

When will my vision be normal again?

You can return quickly to many everyday activities, but your vision may be blurry. The healing eye needs time to adjust so that it can focus properly with the other eye, especially if the other eye has a cataract. Ask your doctor when you can resume driving.
If you received an IOL, you may notice that colors are very bright. The IOL is clear, unlike your natural lens that may have had a yellowish/brownish tint. Within a few months after receiving an IOL, you will become used to improved color vision. Also, when your eye heals, you may need new glasses or contact lenses.

What can I do if I already have lost some vision from cataract?

If you have lost some sight from cataract or cataract surgery, ask your eye care professional about low vision services and devices that may help you make the most of your remaining vision. Ask for a referral to a specialist in low vision. Many community organizations and agencies offer information about low vision counseling, training, and other special services for people with visual impairments. A nearby school of medicine or optometry may provide low vision services.

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what is the cataract?

A cataract is a cloudy or opaque area in the normally clear lens of the eye. Depending upon its size and location, it can interfere with normal vision. Most cataracts develop in people over age 55, but they occasionally occur in infants and young children.



Usually cataracts develop in both eyes, but one may be worse than the other. Reasearchers have linked eye-friendly nutrients such as lutein/zeaxanthin, vitamin C, vitamin E, and zinc to reducing the risk of certain eye diseases, including cataracts.

The lens is located inside the eye behind the iris, the colored part of the eye. The lens focuses light on the back of the eye, the retina. The lens is made of mostly proteins and water. Clouding of the lens occurs due to changes in the proteins and lens fibers.

The lens is composed of layers like an onion. The outermost is the capsule. The layer inside the capsule is the cortex, and the innermost layer is the nucleus. A cataract may develop in any of these areas and is described based on its location in the lens:

• A nuclear cataract is located in the center of the l
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  ens. The nucleus tends to darken changing from clear to yellow and sometimes brown.

• A cortical cataract affects the layer of the lens surrounding the nucleus. It is identified by its unique wedge or spoke appearance.

• A posterior capsular cataract is found in the back outer layer of the lens. This type often develops more rapidly.

Types of Cataracts
Nuclear cataract	Cortical cataract	Posterior capsular cataract
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Normally, the lens focuses light on the retina, which sends the image through the optic nerve to the brain. However, if the lens is clouded by a cataract, light is scattered so the lens can no longer focus it properly, causing vision problems.

Cataracts generally form very slowly. Signs and symptoms of a cataract may include:

• Blurred, hazy, or vision
• Reduced intensity of colors
• Increased sensitivity to glare from lights, particularly when driving at night
• Increased difficulty seeing at night
• Change in the eye's refractive error

While the process of cataract formation is becoming more clearly understood, there is no clinically established treatment to prevent or slow their progression. In age-related cataracts, changes in vision can be very gradual. Some people may not initially recognize the visual changes. However, as cataracts worsen vision symptoms tend to increase in severity.

For more information: http://www.aoa.org/x4714.xml

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What Is Eye Laser Surgery?

It is an oft quoted sentence that beauty lies in the eyes of beholder. However, if you are dogged by poor vision and find it quite difficult to concentrate and focus on your surroundings, it is best advised to get the eye laser surgery so as to rectify the vision and improve upon the eyesight in an hassle free way. Eye laser surgery is also known as LASIK an abbreviated form for Laser Assisted in situ Keraomileusis that is a well known refractive laser eye surgery to rectify cases of myopia, hyperopia and astigmatisms.

 

Eye laser surgery or LASIK was found by Spanish ophthalmologist Jose Barraquer who in 1950’s developed microkeratome that supported the process of cutting thin cornea flaps in the process of Keraomileusis. In the eye laser surgery procedure, there are several procedures that are looked into before operating the patient for eye laser surgery. In the eye laser surgery, a thin flap is created in the eye so that it can be folded and remodeled with laser surgery.

 

In order to begin with the eye laser surgery, patients who have been wearing contact lenses are asked to stop wearing them a week before the eye laser surgery. However, the patients who want to undergo an eye checkup with the use of pachymeter to determine the thickness and surface contour of eye cornea.

 

With the use of low power laser, a topographer draws a map of the cornea as it helps in detection of astigmatism and various other irregularities that are some times present with the shape of cornea. This information is quite helpful in providing the exact details of the eye. During the eye laser surgery, the patient is given an antibiotic dose so that he/she does not develop an infection.

 

In the eye laser surgery, it is a two stage operation where a corneal flap is created and in the second step laser remodeling is carried out followed out by the reposition of the flap and postoperative care. In the flap creation during the eye laser surgery, a corneal suction ring that helps in the creation of the flap with the use of microkeratome blade or a femtosecond laser microkeratome that creates many tiny bubbles in the cornea.

 

After this process, a hinge created at the end of eye flap that reveals stroma. After this step, the corneal stroma is remodeled with excimer laser in such a way that it does not damage the stroma. In this process, the tissue layers are removed. This operation is carried out in such a way that it is painless incision. Once the laser has remodeled the stromal layer, the LASIK flap is repositioned and checked for the presence for any air bubbles or debris.

 

The flap heals naturally and one has to be careful for the eye till it is completely cured. In order to help the healing process, anti inflammatory eye drops and antibiotics are used and patient is recommended to use dark glasses to avoid direct exposure to sunlight. Finally, when the eye heals, the vision is restored and one gets freedom from myopia and hyperopia.

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