Visual impairment

From ArticleWorld

A visual impairment represents partial or complete loss of vision.

Visual impairment, as a legal term, is quite controverted, and often subject to local civil or medical regulations. However, some standardized terms exist and delimit a number of visual impairments, which include:

• Partially sighted. This term denotes a loss of sight or some other visual problem that results in the need for special education techniques.

• Low vision. This term denotes a severe sight problem, not only compared to the functional loss of distance sight. In general, anyone who is not able to read a book or a newspaper at normal distance, even with eyeglasses, will fall into this category. For these people, education should combine a number of special techniques, as they will be able to read if the letters are printed at the correct size. Light adjustment may be required at times, and braille-based educational material may also be required.

• Legally blind. This term indicates a visual impairment that causes a severe loss of vision, typically less than 20/200 in the strong eye.

• Totally blind. This term indicates that the person has lost his or her vision completely. Totally blind students require braille-based educational material, or other non-visual learning material.

These terms are important for education, as they often make the difference between a child who studies in a normal school and one who studies in a special school.

Causes

There are many causes of visual impairment, including congenital disorders, corneal infections, diabetic retinopathy, ingestion of some chemical substances (like methanol) or some other physical or chemical causes. In some cases, the progress of the affection can be stopped, or even reversed completely.

Codes

• ICD-10 H54
• ICD-9 369