low vision

signs of Low Vision

Difficulty recognizing a familiar face
Difficulty reading -- print appears broken or distorted
Difficulty seeing objects and potential obstacles such as steps, curbs, walls and furniture


Vision Is a Continuum

Vision is a complex sense, encompassing the ability to perceive detail
(acuity), color and contrast, and to distinguish objects. These
capacities can diminish naturally with age. While most visual changes
can be corrected by glasses, medicine or surgery, visual changes caused
by eye disease, poor health or injury can cause permanent vision loss.
If the loss is total, the result is blindness. If it is partial, the
result is a vision impairment known as "low vision." A person with low
vision has severely reduced visual acuity or a significantly obstructed
field of vision -- or both.


Low Vision = Usable Vision

People with low vision retain some usable vision. Ophthalmologists and
optometrists specializing in low vision care can evaluate patients and
prescribe optical devices to maximize remaining vision.

Improving Visual Functioning with the Help of Devices

To a person with low vision, a visual image -- whether a sentence from
a book or a crosswalk at a busy intersection -- may appear distorted,
blurred or incomplete. But with the help of low vision devices, the
quality of the image can usually be improved. One or more of these
devices may be prescribed or recommended after a low vision specialist
thoroughly evaluates a person's remaining visual function.

Spectacles for Reading

Half glasses with reading prisms

High-powered reading lenses

Microscopes

Reading telescopes

High-powered bifocals

Telescopes for Distance Vision

Hand-held monocular

Hand-held binocular

Spectacle mounted

Focusable, non-focusable or auto-focus

Absorptive Lenses

Photochromic

Ultraviolet (UV) blocking

Gradient tints

Stand Magnifiers

Adjustable stand

Video Magnifiers

Enlargers for reading

Black-and-white or color

Hand Magnifiers

Illuminated

Non-illuminated

Adaptive devices (non-optical)

Large-print clocks, timers, calculators, remote controls, watches, books

Bold, felt-tipped pens

Signature and writing guides

Talking watches and clocks and more ...

Comprehensive Low Vision Services

Low vision services are provided by specially trained professionals in
a number of settings: hospitals, vision rehabilitation organizations,
private optometric and ophthalmologic practices, and educational and
university facilities. These services may include:

Functional vision examinations
Instruction to help patients adjust to, and reap the maximum benefits
from, optical devices such as high-power spectacles, magnifiers and
telescopes
Trial-period loans of low vision devices
Recommendations for adaptive devices that reduce glare, as well as for
special lighting, large print material, video magnifiers and adaptive
computer technology
Prescription of low vision optical devices
Follow-up care as needed, including additional low vision instruction and training
Introduction/referral to other vision rehabilitation services,
including orientation and mobility training, independent living
programs and counseling
Vision Rehabilitation Is the Key to Independence

In addition to learning how to use optical devices, people with low
vision can acquire new strategies for: accomplishing everyday tasks,
working productively, coping with vision loss and getting around
safely. The adaptive process, in coordination with low vision services,
is known as vision rehabilitation; its goal is to equip people who are
visually impaired with the skills and confidence needed to function as
independently as possible.