What Is Blindness?
Blindness is a condition that refers to the inability of an individual to see. This is a permanent type of vision loss that cannot be corrected using prescription eyewear or surgery. Blindness can be partial or complete. An individual who has partial blindness has very limited vision that is often accompanied by blurry vision, while someone who experiences complete blindness is not able to see anything at all.
What Is Vision Impairment?
Vision or visual impairment refers to loss of vision to a certain degree that affects the ability of an individual in performing daily tasks. The eyes of an individual who has vision impairment cannot be corrected to a “normal level” despite eyeglasses or contact lenses. However, certain devices and surgery may be performed to preserve vision and prevent further vision loss.
Leading Causes of Blindness
Blindness and vision impairment can often be traced to various eye conditions, the most common of which are:
- Cataracts – Considered as the leading cause of blindness and visual impairment across the globe, cataracts are characterized by clouding in the eye’s natural lens. Cataracts become more common with age, frequently afflicting those over the age of 65, but the condition can also develop as a result of an eye injury.
- Uncorrected Refractive Errors – Some of the most common refractive errors are myopia, astigmatism and hyperopia. When these are not treated early enough, they can lead to blindness and visual impairment. These usually happen with children who are yet unable to identify problems with their vision.
- Glaucoma – This refers to a series of eye conditions that result in damage to the optic nerve. Glaucoma is commonly caused by an abnormal build-up of fluid and pressure in the eyes, which, if not corrected promptly, can cause irreversible vision loss.
- Macular Degeneration – Despite the absence of pain and other noticeable symptoms, macular degeneration slowly damages the retina’s macula, which is responsible for one’s central vision. Abnormal blood vessels that leak fluid or blood into the macula are the primary cause of this condition.
- Injuries – Unforeseen or unexpected injuries while working, playing or engaging in more physical activities are also primary risk factors that can cause blindness and visual impairment. This is especially true for injuries that affect the cornea, which serves as a structural barrier that protects the eyes.
- Heredity – Genetic factors play a key role when it comes to vision impairment and blindness. Retinal degeneration, congenital cataracts and eye malformations are the most common inherited eye diseases.
- Diabetic Retinopathy – Diabetes is a condition that damages the blood vessels in the retina because of high blood glucose levels. When the retina is damaged, vision impairment can occur.
- Amblyopia – Also known as lazy eye, this is a condition wherein one of the eye’s vision is poor or damaged. This happens because the eye and the brain do not function or work properly together.