What Is VISUAL IMPAIRMENT? VISUAL IMPAIRMENT Definition & Meaning
Channel: Audiopedia
Date: 2018-11-24

What is VISUAL IMPAIRMENT, What does VISUAL IMPAIRMENT mean, VISUAL IMPAIRMENT meaning, VISUAL IMPAIRMENT definition, VISUAL IMPAIRMENT explanation

Visual impairment, also known as vision impairment or vision loss, is a decreased ability to see to a degree that causes problems not fixable by usual means, such as glasses.[1][2] Some also include those who have a decreased ability to see because they do not have access to glasses or contact lenses.[1] Visual impairment is often defined as a best corrected visual acuity of worse than either 20/40 or 20/60.[5] The term blindness is used for complete or nearly complete vision loss.[5] Visual impairment may cause people difficulties with normal daily activities such as driving, reading, socializing, and walking.[2]

The most common causes of visual impairment globally are uncorrected refractive errors (43%), cataracts (33%), and glaucoma (2%).[3] Refractive errors include near sighted, far sighted, presbyopia, and astigmatism.[3] Cataracts are the most common cause of blindness.[3] Other disorders that may cause visual problems include age related macular degeneration, diabetic retinopathy, corneal clouding, childhood blindness, and a number of infections.[6] Visual impairment can also be caused by problems in the brain due to stroke, premature birth, or trauma among others.[7] These cases are known as cortical visual impairment.[7] Screening for vision problems in children may improve future vision and educational achievement.[8] Screening adults without symptoms is of uncertain benefit.[9] Diagnosis is by an eye exam.[2]

The World Health Organization (WHO) estimates that 80% of visual impairment is either preventable or curable with treatment.[3] This includes cataracts, the infections river blindness and trachoma, glaucoma, diabetic retinopathy, uncorrected refractive errors, and some cases of childhood blindness.[10] Many people with significant visual impairment benefit from vision rehabilitation, changes in their environment, and assistive devices.[2]

As of 2015 there were 940 million people with some degree of vision loss.[4] 246 million had low vision and 39 million were blind.[3] The majority of people with poor vision are in the developing world and are over the age of 50 years.[3] Rates of visual impairment have decreased since the 1990s.[3] Visual impairments have considerable economic costs both directly due to the cost of treatment and indirectly due to decreased ability to work.
Source: Wikipedia.org