A low-vision evaluation will help you and your doctor find ways to
make the best use of your remaining vision.
Your doctor will ask questions to find out how your vision loss has
affected your life and what changes you have already made to cope with reduced
vision. Talk with your doctor about your needs and goals. Questions may include
The iris is a circular, pigmented membrane that provides the eye its color and the opening in the center is the pupil of the eye.
The iris is made up of muscular fibers that control the amount of light entering the pupil so that you can see clearly. The iris accomplishes this task by making the pupil smaller in bright light and larger in dim light.
In some people, the iris can become inflamed. This is termed iritis.
What are the problem areas associated with your
vision loss? How has your life changed? What activities have become harder, and which ones are the most important to you?
Can you do
home-based tasks using near vision, such as reading your mail or a newspaper or
managing bank accounts and paying bills? Have you tried using a magnifying
What sort of lighting do you have in your home? Do you use a
night-light? The doctor may ask other questions about your home
Can you do tasks that require distance vision, such as
recognizing faces or seeing traffic signals? Are you still able to
Can you still travel and function in your environment? Do
you bump into obstacles, such as curbs, or miss steps? Can you find items you
want and count your money when shopping? If you are still working, does your
vision loss affect how well you can do your job?
Other questions may deal with your current living situation, whether
you live alone, and what sort of assistance is available to you. Your family
members or others close to you may also be asked to provide information.
Exams for remaining visual ability
Your doctor will do visual tests to find out the quality of your
remaining vision, including:
Visual acuity for both near and distance
vision. Visual acuity tests measure the eye's focusing power and your ability
to see details at near and far distances. They usually involve reading letters
or looking at symbols of different sizes on an eye chart. These tests will also
take into account any
refractive error in your vision, such as
nearsightedness or farsightedness.
Defects in both
central vision and side (peripheral) vision. These
tests look for flaws and blind spots (scotomas) in your visual field, which is
the entire area seen when your gaze is fixed in one direction. The complete
visual field is seen by both eyes at the same time, and it includes the central
and peripheral visual fields.
Contrast sensitivity. These tests
measure your eye's ability to distinguish objects and their surroundings based
on differences in brightness or color (contrast), rather than shape or
location. The tests may also show how much light (illumination) you need to be
able to distinguish objects with similar brightness or color (low contrast).
Because side (peripheral) vision is less sharp than central vision, contrast
may play a more important role in helping you locate and identify objects if
you lose some central vision.
Your doctor may also conduct vision tests for brightness acuity
(which may show how sensitive you are to glare), color perception, and how well
your eyes work together to provide depth perception.