A perimetry test (visual field test) is a method of measuring an individual’s entire
scope of vision, that is their central and peripheral (side) vision. Visual field
testing actually maps the visual fields of each eye individually. It can help find
certain patterns of vision loss. This may mean a certain type of eye disease is
present.
- It is a good test to find vision loss caused by the eye disease- glaucoma. Regular
perimetry tests can be used to see if treatment for glaucoma is preventing further
vision loss.
- The amount of peripheral vision loss is linked to the amount of optic nerve damage.
- In addition, visual field tests are useful for detection of central or peripheral
retinal disease, eyelid conditions such as ptosis or drooping, optic nerve disease,
and diseases affecting the visual pathways within the brain.
This test is conducted by our optometrist and interpreted by the doctor You sit
at a table and place your head in a chin rest, so that your head is comfortable
and steady.
- Each eye is tested separately, and the eye not being tested is covered with a patch.
- The proper focusing lens (eyeglass) for your eye is placed in front of your eye
for the best vision, but you do not need to wear your own glasses.
- Your eye looks straight ahead into a large bowl that has a fixed spot in the center
on which you focus.
- The optometrist may move objects or lights of different size and brightness from
the side in toward a spot where you “see” the object in your side vision. As soon
as you “see” the object, you press a button to record your visual field. The same
test may also be done using stationary objects of light that “blink” on and off
in various parts of the visual field.
- The same test is repeated for the other eye
It usually takes about 25 minutes per eye for the test. After the test one can resume
normal activity. Our doctor will assess the results, depending on results, further
follow-ups, evaluation, or treatment may be recommended.