A cataract is a blur of the natural lens of the eye, behind the iris and pupil.
Cataract are the most common cause of vision loss in people over the age of 40 and are the main cause of blindness in the world.
According to Prevent Blindness America (PBA), there are more cases of cataracts worldwide compared to glaucoma, macular degeneration and diabetic retinopathy.
Today, cataracts affect more than 22 million Americans aged 40 and over. And as the American population of centuries, more than 30 million Americans are expected to have cataracts by the year 2020, says PBA.
Cataracts types
A subcapsular cataracts
It appears on the back of the lens. People with diabetes or those receiving high doses of steroid drugs are at greater risk of developing subatomic cataracts.
A nuclear cataract
It is formed deep in the central zone (core) of the lens. Nuclear cascades are usually associated with aging.
A Cortical cataract
It is characterized by a white, spherical opacity that begins at the periphery of the lens and operates in the center in a way that resembles the rays. This type of cataracts occurs in the lens cortex, which is the part of the lens surrounding the central core.
Symptoms and signs of Cataracts
Cataract begins a little and initially has little effect on your vision. You may notice that your vision is blurry, like seeing through a cloudy piece of glass or seeing a painting.
How the same landscape looks like someone he sees normally. The cloudy, blurred vision may mean you have a cataract.
A cataract can make light from the sun or a lamp very bright or sharp. Or you can observe during the night that the projectors involved cause more reflection than before. Colors may not look as bright as ever.
The type of cataract you have will affect exactly the symptoms you will experience, and how soon they will happen. When a nuclear cascade develops initially, it can bring a temporary improvement to your near vision, called "second vision".
Unfortunately, improved vision is short-lived and will disappear as the cataracts get worse. On the other hand, a subtype cascade may not produce symptoms until it develops well.
If you think you have a cataracts, visit a doctor to make sure.
What Causes Cataracts?
The lens in the eye looks like a camera lens, focusing the light on the retina for clear vision. It also regulates the focus of the eye, allowing us to see things as close and far as possible.
The lens mainly consists of water and proteins. The protein is arranged in an accurate way that keeps the lens clean and lets light pass through it.
But as we age, some protein can accumulate and begin to blur a small area of the lens. This is a cascade and over time it can grow and form a cloud more than the lens, making it harder to see.
Nobody knows why the lens of the eye changes as we age, forming waterfalls. However, researchers around the world have identified factors that may cause cataracts or are associated with cataract development.
In addition to age progress, cataract risk factors include:
Ultraviolet radiation from sunlight and other sources
Diabetes
Hypertension
Smoking
Prolonged use of corticosteroids
Statins drugs used to lower cholesterol
Previous eye injury or inflammation
Previous eye surgery
Hormone replacement therapy
Significant consumption of alcohol
High myopia
Family history