Blindness is called a state without sight. An individual when becomes blind is not able to see with the eyes. It refers to a condition of complete loss of vision in which a person cannot differentiate between light and dark surroundings by both the eyes.
Blindness is nowadays used to describe severe visual impairment in one or both the eyes. The loss of vision cannot be rectified even with the use of eye glasses or contact lenses, medicines or any type of surgery.
|ICD-10||H54.0, H54.1, H54.4|
Visual impairment is termed as blind in the people who are not able to see completely. Partial visual impairment is partial blindness in which people have limited vision.
Almost 300 to 400 million people have visual impairment all around the world because of various eye diseases. 50 million people are completely blind out of the above mentioned.
The common symptom of blindness is inability of the individual to see. Sometimes symptoms are seen before the disease leads to blindness. These symptoms are, pain in eyes, watery discharge from eyes, foreign body feeling in the eye and more. These symptoms change according to the underlying disease which can lead to visual impairment.
Complete blindness is difficult to treat. Blindness caused due to infectious diseases can be treated with proper medicines and drops. Visual impairment due to cataracts can be rectified by surgery on the eye. Blindness due to deficiency in vitamin A can be treated by intake of regular nutritional supplemented food or daily doses of vitamin A.
Blindness can be caused due to various reasons. Experts found major causes of blindness worldwide as cataracts, onchocerciasis, trachoma, leprosy and deficiency of vitamin A and traumatic injury.
Some more causes of blindness are
Color blindness, night blindness and snow blindness are some of the types of blindness. Color blindness causes inability in a person to identify some colors. Night blindness reduces the ability of a person to see in dim light or night. Snow blindness occurs when a person is exposed to ultraviolet rays and loss of vision takes place. But in all these types of blindness, people do have sight. They are partially blind.
Absolute blindness results in complete loss of vision and person cannot differentiate in light and dark environments.