What is a Cataract
A cataract is a clouding of the lens. The lens is situated behind the iris and the pupil. It works like a camera by focusing the incoming light onto the retina. The lens adjusts the eye's focus, letting us see things clearly both up close and far away.
With a cataract the protein in a lens, which is normally arranged in a precise way, has clumped together and has formed a cloud in an area of the lens.
Over time, it may develop into a larger area of the lens, making it harder to see.
There are three types of cataracts:
A nuclear cataract.This cataract is located in the nucleus - the center of the lens and is most often seen as it forms.The cause of this cataract is likely due to changes in the protein structure as we grow older.
A cortical cataract.This cataract develops from the outside of the lens extending over time to the center. This cataract occurs often by people with diabetics.
A subcapsular cataractThis cataract begins at the back of the lens. People with diabetes, high farsightedness, retinitis pigmentosa or those taking high doses of steroids have a higher risk of developig this form of cataract.
The term "age-related" often used when cataracts are mentioned is misleading because people can have an age-related cataract in their 40's and 50's. However during these ages, most cataracts are small and do not affect vision. Most cataracts have a serious impact on ones eyesight after age 60 .
What are the symptoms
Each type of cataract has its own symptoms. With a nuclear cataract you may notice an improvement in your near vision. This is called 'second sight'. However this will disappear when the cataract gets worse.
A subcapsular cataract may only give symptoms in a later stage when it is more developed.
The most common symptoms of a cataract are:
- Cloudy or blurry vision.
- Colors seem to be 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 glasses or contact lenses.
When a cataract is small you will hardly notice it. You may find that your vision is a little blurry, like looking through a cloudy piece of glass. Cataracts tend to develop slowly, so your vision might get worse gradually. Over time, the cloudy area in the lens may get larger, as the cataract increases in size. Seeing may become more difficult and your vision may get duller or blurrier.
Another symptom of cataracts is that the clear lens slowly changes to a yellowish/brownish color, adding a brownish tint to your vision.
At first, the amount of tinting may be too small to cause a vision problem. Increased tinting over time may make it more difficult to read and perform other activities. This does however not affect the sharpness of the image transmitted to the retina.
If your lens discoloration is in an advanced state, you may not be able to identify blues and purples. Instead, you may be seeing black.
What causes Cataract
A lot of research has been done to what the cause of cataracts is and is still happening. So far it is unclear why, as we age, the protein starts to clump. However, to just write it down to age is not correct as not everyone experiences having cataracts.
Many studies suggest that exposure to ultraviolet light is associated with the development of cataracts. This is one of the reasons why eyecare specialists recommend wearing sunglasses and a wide brimmed hat. A 2005 study conducted in Iceland suggests that airline pilots have a higher risk of developing nuclear cataract than non-pilots. The cause may be exposure to cosmic radiation. A similar theory suggests the same counts for astronauts.
It has also been suggested that people people who use steroids, diuretics and major tranquilizers or people with diabetes are at risk for developing a cataract.
Other risk factors are: air pollution, cigarette smoke and heavy alcohol consumption. Several studies indicated that lead exposure is a risk factor. However this research was not extensive enough to determine whether lead can definitely put you at risk, and if so, whether the risk is from a one-time dose at a particular time in life or from chronic exposure over years.
How is Cataract diagnosed
An ophthalmologist can diagnose a cataract and monitor its development by doing a comprehensive eye examination,.
This usually includes:
Visual acuity test: This is a common eye chart test where the doctor will ask youl to read a letter chart to see how good your sight is at various distances.
Pupil dilation: In this test, the pupil (the round black centre of your eye) is widened with eye drops thus enabling the doctor to see more of the lens and retina and look for other eye problems.
Other eye tests:
How can a Cataract be treated
When symptoms begin to appear, you may be able to improve your vision for a while using glasses with new prescriptions, strong bifocals, magnification, appropriate lighting or other visual aids. However these do not imporve your cataract but are merely aids to help you see better. As glasses and contacts can make your eyesight worse we advice to use these methods as a last resort.
We advice you to use natural means to treat and forestall cataracts.
A diet high in antioxidants, such as beta-carotene (vitamin A), selenium and vitamins C and E, may forestall cataract development. Lower your intake of salt as eating a lot of salt increases your risk of cataracts. You should only consider surgery when your cataracts have progressed so far that they seriously impair your vision.
With cataract surgery the clouded lens is removed and replaced by a clear, plastic intraocular lens (IOL). There are many new kinds of IOLs available. One example is an IOL that lets patients see at all distances, not just one. Another new IOL blocks both ultraviolet and blue light rays, which research indicates may damage the retina. Please consult your eye specialist if you are interested in one of these IOLs.
There are also situations when a cataract should be removed even if it does not cause problems with your vision. For example if it prevents examination or treatment of another eye problem, such as age-related macular degeneration or diabetic retinopathy. Once a cataract is discovered it does not mean you need surgery straight away. In fact, you might never need cataract surgery. Get your vision tested regularly, so you can discuss with your eye specialist if and when you might need treatment.
Cataract surgery is successful in restoring vision. It is the most frequently performed surgery in the United States, with over 1.5 million cataract surgeries done each year. Patients who have had cataract surgery regain very good vision, somewhere between 20/20 and 20/40.
After the operation your vision may be blurry for a while but you can return to many everyday activities. The operated eye needs time to adjust so that it can focus properly with the other eye, especially if the other eye still has a cataract. Consult your doctor to find out when you can resume driving.
If you received an IOL, you may notice that colors are very bright. This is because you are used to looking through a clouded lens while the IOL is clear. Within a few months after receiving an IOL, you will get used to improved color vision.
What are the risks of surgery
There are some common problems which can occur after surgery. These may include blurring from swelling, increased pressure, inflammation (pain, redness, swelling), and sometimes bleeding. More rare and serious problems include loss of vision, infection or light flashes. You should contact your eye doctor If you experience increasing pain or a worsening of vision after surgery. Almost all problems can be treated successfully with prompt medical attention,
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.
A condition called an after-cataract can develop months or years after cataract surgery. This cataract is caused by the eye tissue that encloses the IOL becoming cloudy after the operation and thus may blur your vision.
An after-cataract is usually treated with a laser. Your eye specialist uses a laser to make a tiny hole in the eye tissue behind the lens so light can pass through. This procedure is called a YAG laser capsulotomy. It is painless and rarely results in eye problems. Your doctor may give you eyedrops to lower your eye pressure before or after the procedure as a precaution.
How can Eyerobics help
The Eyerobics program is based on the Bates Method, a well known method of eye exercises developed by an ophthalmologist. Although we do not state that the Eyerobics program improves a cataract (as the exercises focus on eye muscles, not on the condition of the lens), people who have suffered from cataracts have shown significant improvement in their sight by doing this program to improve their eyesight. This is because Eyerobics can address the side effects which often are a result of having a cataract: short or near sightedness, far sightedness, astigmatism, etc.
"Since I got your exercises, I have been doing them and my sight is improving all the time. A few years ago however I discovered my eyesight was deteriorating and a specialist in Geelong told me I had a heamorage behind my left eye, a cataract completely covering it, and a scar on my iris and I wouldn't see ouit of it again. Professor Grock in Melbourne told me the same thing. It gave me a shock!
Well I have kept up the exercises and now if I put my hand over my right eye, I am seeing better and better. One of the doctors said recently I have got better sight in my right eye than anyone they have treated over 80 years of age. I can still read ordinary writing and books and I still do a bit of craft work. My dried flower pictures have gone all around the world. I am now working for Red Cross and have jus crochet a rug and am knitting cats!"
R. H. Clarke, Bungaree, Australia