If the light rays and focus on the retina, we see clearly. When they focus a little in front of the retina or behind it, we notice blur.
The lens is flexible and in normal, clear vision, small muscles change the convexity / concavity of its shape, so that we can focus at all distances. The lens is made of water and protein is arranged so that it is very translucent, allowing light to pass unhindered through the retina.
As we age
The lens gradually changes as we age. The arrangement of protein and water, so that some changes of the protein clumps together, creating a slight obstruction of the light rays. This is a cataract. Cataracts, start small, grows very slowly and causes the light rays to scatter as they pass. That does not make them to focus on the retina and we experience and blur-brightness. If left untreated long enough, the cataract in the lens to extend, resulting in a loss of vision.
The earlier a cataract diagnosed and treated, the better we can keep our vision.
Three types of cataracts
• Nuclear cataract begins – in the center of the lens form, outward-spreading, caused by the aging of the lens
• Cortical cataracts begin – at the edge of the lens form, and extends to the inside, which often caused by diabetes
• Subcapsular Cataract – start to form on the back of the lens, and most frequently diagnosed in diabetics, people with high doses of steroids associated with retinitis pigmentosa, or with severe farsightedness.
Causes of Cataracts
Research is under way, as the causes. We do not know why an aging star should make or what other factors could cause contributing to their education.
Some studies have pointed to ultraviolet light, so some eye doctors, we recommend wearing sunglasses and a shady hat protect our eyes
Other studies suggest cosmic radiation as a causal factor, it seems that pilots frequently develop cataracts
People with diabetes experience eye changes due to vascular causes. But they also get cataracts more frequently as people on steroids, tranquilizers and diuretics. It is still unknown whether they contribute to medical conditions or medications, more about cataracts.
Other studies have pointed out:
• excess salt
• Heavy alcohol consumption
• Smoking
• Lead
Symptoms of Cataracts
For all three types of cataracts, the symptoms are mild at first. You can only observe in one eye.
• blurring or clouding
• Reduced brightness of the color
• glare from light sources, especially at night
The symptoms over time to increase slowly. But deteriorating vision does not need an accompaniment to aging. A good eye doctor will be able to determine what type of cataract you have and advise you about cataract surgery. Cataract Surgery
This is the most common out-patient surgery performed in the U.S. and almost all the people who achieve it have excellent vision.
• Your doctor will examine your eyes to determine the right energy for the intraocular lens (IOL), it is for you implant. The IOL is made of lightweight plastic.
• A local anesthetic is given and a relaxing medication (only in some patients).
• With the help of a microscope makes the surgeon makes a small incision.
• Ultrasound can be the first break up the natural lens, so it can be removed easily, or sometimes it is just as it is. The lens of the posterior membrane (posterior capsule) is left intact.
• The IOL is inserted and gently closed the incision. Dissolvable sutures are used.
• Then, your doctor can go eye protection and you can go home the same day.
In some cases, the posterior capsule becomes cloudy after cataract surgery. This makes your vision blurred again, but it can be treated with a laser. The eye surgeon makes a small opening in the capsule to allow light reaches the retina, as it should.