LOW VISION

Vision impairments result from conditions that range from the presence of some usable vision, low vision, to the absence of any vision, total blindness. Low vision is a term that describes a person with a vision impairment that cannot be improved by correction but has some usable vision remaining. Legal blindness is defined as 20/200 or less in the better eye with the best possible correction. Errors of refraction, diseases of the eye, and other vision-related conditions are usually the cause of vision loss. Each of these  

categories includes more specific disorders, which are described below.

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COMMON ERRORS OF REFRACTION

  • Myopia (Nearsightedness): Close

  • objects look clear while distant objects appear blurred.

  • Hyperopia (Farsightedness): The ability to see objects clearly at a distance while close objects appear blurry.

  • Astigmatism: Due to the irregular curvature of the cornea, vision is blurry for both near and far objects.

  • Presbyopia: The eye lens becomes less elastic (associated with aging) and produces blurred vision when focusing on near objects.

COMMON DISEASES OF THE EYE

  • Cataracts: Clouding of the eye’s lens that causes l oss of vision.

  • Glaucoma: Pressure inside the eye is elevated and can cause damage to the optic nerve, which results in damage to peripheral vision.

  • Macular Degeneration: There is a disturbance of blood vessels in the eye resulting in progressive loss of central vision.

  • Retinitis Pigmentosa: There is a degeneration of pigment in the eye that is needed to absorb light and create visual images, leading to “tunnel vision” and night blindness.

  • Retinopathy (due to Diabetes): Retinopathy typically affects the blood circulation of the retina, which causes blotchy vision.

OTHER VISION RELATED CONDITIONS

  • Night Blindness: Night blindness results from pigmentary degeneration of the retina, which leads to difficulty seeing in low light.

  • Color Vision Deficiency: A color vision deficiency occurs when cone cells of the retina, which provide daylight and color vision, are affected and there is difficulty distinguishing among colors. Typically this only involves certain hues, for example a red–green deficiency; total color blindness (achromatic vision) is rare.

  • Lack of Depth Perception: A lack of depth perception is often caused by the loss of sight in one eye, resulting in difficulty with foreground/background discrimination.

  • Floaters: Floaters are small specks or clouds moving in the field of vision.

ACCOMMODATING STUDENTS WITH LOW VISION

People with low vision may develop some of the limitations discussed below, but seldom develop all of them. Also, the degree of limitation will vary among individuals. Be aware that not all people will need accommodations to perform their jobs and many others may only need a few accommodations. The following is only a sample of the possibilities available. Numerous other accommodation solutions may exist.

QUESTIONS TO CONSIDER:

  1. What limitations is the student experiencing?

  2. How do these limitations affect the student performance?

  3. What specific job tasks are problematic as a result of these limitations?

  4. What accommodations are available to reduce or eliminate these problems? Are all possible resources being used to determine possible accommodations?

  5. Has the student been consulted regarding possible accommodations?

  6. Once accommodations are in place, would it be useful to meet with the student to evaluate the effectiveness of the accommodations and to determine whether additional accommodations are needed?

  7. Do teachers and personnel need training?

ACCOMMODATION IDEAS





 

By Limitation of: Blind - Total

  • Accessible Mobile Phones

  • Accessible Telephones

  • Apps for Individuals with Vision Impairment

  •  External Computer Screen Magnification

  • Head-mounted Magnifiers

  • High Visibility Floor Tape and Paint

  • Large Button Phones

  • Large Visual Display for Telephone

  • Lighted Reading Glasses

  • Low Vision Office Supplies

  • Magnification (Hand or Stand)

  • Optical Character Recognition (OCR) Systems - Scan

  • Portable Video/Electronic Magnifiers

  • Screen Magnification and Screen Reading Combined

  • Screen Magnification Software

  • ​Sewing Aids for Individuals with Vision Impairment

  • Stair Tread/Textured Tape

  • Tactile Timepieces/Watches

  • Talking Alarm Clocks

  • Talking Bar Code Scanner/Reader

  • Talking Blood Glucose Monitors

  • Talking Blood Pressure Monitors

  • Talking Cash Register

  • Talking Coin Counter/Sorter

  • Talking Color Detector

  • Talking Copies

  • Talking Credit Card Terminal

  • Talking Money Identifier

  • Talking Scales

  • Talking Telephones

  • Talking Watches

 
By Class Work Related Function
 

Commute

  • Flexible Schedule

  •  Ridesharing/Carpooling

  •  Telework, Work from Home, Working Remotely

  •  Transportation Assistance

  •  Van Conversion

  •  Walkers

Situations and Solutions

A student in electrical engineering with low vision had difficulty reading visual notifications, both electronic and in print.The student was accommodated with handheld portable magnifiers.

 

 A student could not read books

 

  • A student had low vision and was accommodated with a CCTV magnification device for reading paper documents and screen magnification software for her mobile phone.

  • A student having difficulty reading files due to a vision impairment caused by multiple sclerosis.

  • The school purchased a stand magnifier and added task lighting to the student with flexible submission of classwork.

  • A student with low vision was having some difficulty distinguishing among certain character keys.

  • She was provided with a glare guard for the computer monitor and large print keyboard labels, which significantly enhanced accuracy.

  • A student had color vision deficiency and used corrective lenses that helped her to distinguish color during day-to-day tasks.

  • The school asked parents to provide her with customized prescription goggles to wear at work.  

  • A preschool teacher needed to read books aloud to students during circle time.

 

 

She had difficulty describing and talking about the pictures in the books because of her color vision deficiency. She wanted to be able to describe the pictures accurately in order to help the children learn their colors. She was sometimes able to get help from a teaching assistant, but wanted a more independent solution. A CBR worker discussed free and low-cost apps for identifying colors and suggested that she use an app to familiarize herself with the colors used on various pages in advance. The teacher also made index cards with notes about the pictures that she wanted to describe and taped them to the back cover of each book while reading.