|
F
Eye Health Glossary
A &sdot
B &sdot
C &sdot
D &sdot
E &sdot
F &sdot
G &sdot
H &sdot
I &sdot
J &sdot
K &sdot
L &sdot
M &sdot
N &sdot
O &sdot
P
Q &sdot
R &sdot
S &sdot
T &sdot
U &sdot
V &sdot
W &sdot
X &sdot
Y &sdot
Z &sdot
#
|
farsightedness (hyperopia)
Common refractive vision problem in which the focusing power of the eye is too weak such that an
image comes to focus behind the retina. Farsightedness
(hyperopia) is corrected with convex (plus)
lenses.
Learn more about Farsightedness.
FDA
Food and Drug Administration; an agency of the US Department of Health and Human Services that
regulates the pharmaceutical drugs, devices, and services available to the general public, ensuring
their safety and effectiveness before being used.
field testing
A test that measures
visual field. Most optometry
offices have a machine where small flashes of light appear in the periphery while the patient is
staring straight ahead. Each eye is tested individually and it can take anywhere from 3 to 15
minutes per eye. Field testing is most often used to assess any changes in peripheral vision
due to
glaucoma.
fixation
Deliberate and continuous coordinated eye positioning to maintain view of a target in
central vision.
flashes
Sudden appearance of flashes of light, most often due to the mechanical pulling of
photoreceptors as they are being
tugged on by the
vitreous when it pulls away from the
retina. When the photoreceptors are
stimulated like this, they send signals to the brain just as they would if light stimulated them,
which is why we see flashes of light. The sudden appearance of flashes of light may be a symptom
of a
retinal detachment, which is an
emergency so you should get in touch with your
optometrist immediately if you
experience this symptom.
floaters
Appearance of dark spots within the field of vision. Although they can be caused by infection,
most floaters are simply a normal part of an aging eye, as the
vitreous detaches from the retina. Many people
are living with floaters that have been around for a long time, but if you notice a sudden increase
in the number of floaters that you are seeing, you should visit your
optometrist right away.
fluorescein angiography
A test involving the injection of a fluorescent dye into the arm. The dye travels up the arm and
into the blood vessels in the eye, at which point it is viewed using a specialized camera.
Fluorescein angiography is used to assess blood vessel integrity in
diabetic retinopathy and
macular degeneration.
foreign body
Any object that is found on or in the eye, that is not supposed to be there. All occupations and
hobbies involving flying debris can be a potential hazard, so proper safety goggles should always be
worn. Never try to take a foreign body out of your eye, as it may have penetrated the globe (ie.
gone right through to the inside of the eye) in which case you will be losing fluid from the eye
that is necessary for maintaining the eye's structure.
foreign body sensation
The sensation that there is something in the eye that does not belong (eg. Eyelash). While in most
cases, there actually is something in the eye, there are times when, for example, the cornea is
scratched so that it only feels like there is something in the eye.
fovea
fundus
Literally, “fundus” refers to the bottom of an organ. In opthalmic terms, it refers to the retina
at the back of the eye as viewed through the
pupil. Examination of the fundus is a
crucial component to ensuring health of the eyes.
Fundus photography is quickly becoming a
valuable addition to each
regular eye examination.
|
|
|
|
