Understanding Cataracts

By Author: John Tang
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Cataracts are changes in the clarity of the natural lens inside the eye that gradually degrade visual quality and may lead to legal blindness or significantly low vision.

The term cataract is derived from the Greek word cataractos, which describes rapidly running water. When water is turbulent, it's transformed from a clear medium to white and cloudy. Greek observers noticed a similar changes in the eyes and with no knowledge of working of the eye considered cataracts an accumulation of turbulent fluids.

Cataracts development is generally very slow with the normal process of aging but in some instants can have a rapid onset. While it does not spread from one ye to another cataracts most commonly develop in both eyes but it is not uncommon for one eye to advance more rapidly than the other.

According to the World Health Organization age-related cataracts are responsible for 48% of world blindness. In the United States studies report that cataracts affect 42% of patients between of 52 and 64; 60% of those 65 to 74 years and 91% of those between the ages of 75 and 85.

Causes & Types

Cataracts ...
... may develop for a number of reasons including long-term exposure to ultraviolent light, exposure to radiation, secondary effects of diseases such as diabetes, hypertension and advanced age, or trauma (possibly much earlier); they are usually the result of denaturizing of the lens protein.

These lenses are made up of mostly water and protein; specific protein within the lens is responsible for maintaining its clarity. Over many years, the structures of the lenses protein is altered, ultimately leading to a gradual clouding of the lens.

Types of cataracts include;

Nuclear- a nuclear cataract occurs at the center of the lens. In it's early stages, as the lens changes the way it focuses light, a patient may become more nearsighted or even experience temporary improvement in reading vision. So-called second sight disappears as the lens gradually turns more densely yellow and clouding overtakes the lens.

Cortical- a cortical cataract begins as whitish, wedge-shaped opacities or streaks on the outer edge of the lens cortex. Problems with glare are common for people with this type of cataract.

Subcapsular - a subcapsular cataract starts as a small, opaque are just under the capsule of the lens. It usually forms near the back of the lens, right in the path of light on it's way to the retina. This type of cataract generally interferes with reading vision, reduced vision in bright lights or halos around lights at night.

Symptoms
Signs and symptoms of cataracts include:
Clouded, blurred or dim vision
Increasing difficulty with vision at night
Sensitivity to light and glare
Halos around lights
The need for brighter light for reading and other activities
Frequent changes in eyeglass or contact lens prescription
Fading or yellowing of colors
Double vision in a single eye
If you have a cataract, light from the sun, lamps or oncoming headlights may seem too bright. Glare and halos around lights can make driving uncomfortable and dangerous. You may experience eyestrain or find yourself blinking more often to clear your vision.
Cataracts don't typically cause any change in the appearance of your eye. Pain, redness, itching, irritation, aching in your eye or a discharge from your eye aren't signs or symptoms of a cataract, but may be signs and symptoms of other eye disorders.
Treatments
The most effective treatment for cataracts is surgery.
The most commonly used form is called phacoemulsification. With the use of a microscope the surgeon will make a very small incision in the surface of the eye and with a small probe use ultrasonic vibrations to dissolve the clouded lens. These tiny fragments are then suctioned out with the same probe and finally an artificial lens is placed into the same thin capsular bag. This type of surgery can in many cases be performed within 30 minutes, requires no stitches and no eye patch after surgery.
Other types of surgery, which are less commonly used, are:
Extracapsular- a procedure mainly used for very advanced cataracts where the lens is too dense to dissolve into fragments. This technique requires a larger incision, injection of numbing medication, stitches, an eye patch after surgery and a slower recovery of vision.
Intracapsular- this surgical technique requires even a larger wound whereby the surgeon removed the entire lens and the surrounding capsule together. The process requires the intraocular lens to be placed in a different location in front of the iris. This method is rarely used today but can still be used in cases of significant trauma.

Prevention
At present, there is no real effective way to prevent the formation of cataracts, so secondary prevention involves controlling other eye diseases that can cause cataracts and minimizing exposure to factors that promote cataracts.
Wearing sunglasses outside during the day might reduce your chances of developing cataracts or having problems with the retina. Some sunglasses can filter out UV light, reducing exposure to harmful UV radiation and might slow the progression of cataracts.
Some people take vitamins, minerals, and herbal extracts to decrease cataract formation. No scientific data prove that these remedies are effective. No topical or oral medications or supplements are proven to decrease the chance of developing cataracts.
A healthy lifestyle might help, just as a healthy lifestyle helps prevent other diseases in the body. Eat a proper diet, get regular exercise and rest, and do not smoke.
If you have diabetes, tight blood-sugar control can delay the otherwise accelerated development of cataracts.
Eat a balanced diet. Include plenty of fruits and vegetables in your diet. While it hasn't been proven clinically eating lots of fruits and vegetables may have a modest effect in preventing or delaying cataracts.
Researchers are continuing to explore new ways to prevent and treat cataracts, such as developing medications that would reduce or eliminate the need for surgery. But, until such a treatment exists, your chances of fully restoring your vision with cataract surgery are excellent if you have no other eye diseases.
For more click on Understanding Cataracts. At Austin County Eye Associates our focus is on you and the best options for your eye vision care.