Types of Visual Impairment

What is age-related macular degeneration (AMD)?AMD is a progressive condition that affects the macula. The macula, located at the back of the eye is a small spot on the retina which is responsible for central vision.

Visual impairment may cause people difficulties with normal daily activities such as driving, reading, socializing, and walking. The most common causes of visual impairment …

There are many causes of blindness. In children, vision impairment may be due to birth defects, often a result of prematurity. Optic nerve damage, injury of the eye(s), and trauma to the part of the brain that controls vision may also result in blindness.

Magnitude. Corneal Opacity accounts for 3.46% of global blindness and 1.65% of global blindness and visual impairment (IAPB Vision Atlas). As a leading cause of blindness in children (Solomon, 2005) and within developing nations, Corneal blindness affects all age groups.

By percentage, DR caused 2.6% of all cases of blindness and 1.9% of all visual impairment in 2010, up from 2.1% and 1.3%, respectively, in 1990. The percentage of blindness caused by DR in 2010 ranged from less than 2% in Southeast Asia and Oceania to 5.5% or greater in southern Latin America.

Glaucoma is the second commonest cause of blindness worldwide. It is estimated that up to 70 million people suffer from this disease, although not all will go blind. Experts predict that this number will only continue to increase.

Refractive errors are eye disorders caused by irregularity in the shape of the eye. This makes it difficult for the eyes to focus images clearly, and vision can become blurred and impaired. Refractive errors include eye problems such as myopia (short-sightedness), hyperopia (long-sightedness) and astigmatism (caused by an irregularly curved cornea).

Trachoma, an eye infection affecting both eyes, is the world’s leading cause of preventable blindness. According to the World Health Organization (WHO), trachoma is responsible for the visual impairment of 2.2 million people, of whom 1.2 million are irreversibly blind.