Blind or Partially Sighted
The two terms most commonly used to describe person’s experiencing vision loss (or visual impairment) are blindness and partially-sighted. Blindness refers to individuals who have no, or very little usable vision. Individuals who are blind will often use a white cane or guide dog to assist with navigating their environment. They may use braille or text-to-speech software to access their course materials.
Individuals who are partially sighted have some usable vision and are often considered to have a visual impairment. Individuals with a visual impairment may experience reduced visual acuity or they may have a severely reduced field of vision such as having sight only at the periphery of their visual field or alternatively, having a small field of vision only centrally.
The functional impacts of a visual impairment can be very different depending on the nature of the vision loss. For example, a person with peripheral vision may have little difficulty navigating their environment since they are able to see objects around them. On the other hand, a person with a small field of central vision may choose to use a cane or guide dog as it may be more difficult for them to detect details in their environment to the left or right. A person with low visual acuity may have little difficulty navigating their environment; however, they may not have sufficient visual clarity to recognize people by sight or to read average sized print. In some cases they may be able to see print or objects more clearly if they hold them closer to their eyes.
Students experiencing vision loss will likely need to access their course materials and exams in alternate formats or with the use of adaptive aids such as magnifiers or text-to-speech software. They may also find it helpful to have additional orientation to the school environment and will benefit from having visual information presented orally during class. Since each student will have their own strategies for access, it is always best to ask the student about what would be helpful for them.
In Canada a person is legally considered to have a visual impairment if their visual acuity after correction (use of glasses or contact lenses) is 20/200 or less in their better eye or if they have a visual field of 20% or less.
For more information on the impacts of this disability and classroom accommodations see Vision.