Floaters and Flashes
What
are floaters?
You may sometimes see small specks or clouds moving in your field
of vision. They are called floaters. You can often see them when looking
at a plain background, like a blank wall or blue sky.
Floaters
are actually tiny clumps of gel or cells inside the vitreous,
the clear jelly-like fluid that fills the inside of your eye.
Although the floaters appear to be in front of the eye, they are
actually floating in the vitreous fluid inside the eye.
While these objects look like they are in front of your eye, they
are actually floating inside. What you see are the shadows they cast
on the retina, the nerve layer at the back of the eye that senses
light and allows you to see.
Floaters
can have different shapes: little dots, circles, lines, clouds or
cobwebs.
What
causes floaters?
When
people reach middle age, the vitreous gel may start to thicken or
shrink, forming clumps or strands inside the eye. The vitreous gel
pulls away from the back wall of the eye, causing a posterior
vitreous detachment. It is a common cause of floaters.
Posterior
vitreous detachment is more common for people who:
- are
nearsighted;
- have
undergone cataract operations;
- have
had YAG laser surgery of the eye;
- have
had inflammation inside the eye.
The appearance
of floaters may be alarming, especially if they develop suddenly.
You should see an ophthalmologist (Eye M.D.) right away if you suddenly
develop new floaters, especially if you are over 45 years of age.
Are floaters ever serious?
The retina
can tear if the shrinking vitreous gel pulls away from the wall of
the eye. This sometimes causes a small amount of bleeding in the eye
that may appear as new floaters.
A torn
retina is always a serious problem, since it can lead to a retinal
detachment. You should see your ophthalmologist as soon as possible
if:
- even
one new floater appears suddenly;
- you
see sudden flashes of light.
If you
notice other symptoms, like the loss of side vision, you should see
your ophthalmologist.
What can be done about floaters?
Because
you need to know if your retina is torn, call your ophthalmologist
if a new floater appears suddenly.
Floaters
can get in the way of clear vision, which may be quite annoying, especially
if you are trying to read. You can try moving your eyes, looking up
and then down to move the floaters out of the way.
While
some floaters may remain in your vision, many of them will fade over
time and become less bothersome. Even if you have had some floaters
for years, you should have an eye examination immediately if you notice
new ones.
What
causes flashing lights?
When
the vitreous gel rubs or pulls on the retina, you may see what look
like flashing lights or lightning streaks. You may have experienced
this same sensation if you have ever been hit in the eye and seen
"stars."
When the vitreous rubs or pulls on the retina, it creates a sensation
of flashing lights.
The flashes of light can appear off and on for several weeks or months.
As we grow older, it is more common to experience flashes. If you
notice the sudden appearance of light flashes, you should visit your
ophthalmologist immediately to see if the retina has been torn.
Migraine
Some
people experience flashes of light that appear as jagged lines or
"heat waves" in both eyes, often lasting 10-20 minutes.
These types of flashes are usually caused by a spasm of blood vessels
in the brain, which is called migraine.
If a
headache follows the flashes, it is called a migraine headache. However,
jagged lines or "heat waves" can occur without a headache.
In this case, the light flashes are called ophthalmic migraine, or
migraine without headache.
How
are your eyes examined?
When
an ophthalmologist examines your eyes, your pupils will be dilated
with eye drops. During this painless examination, your ophthalmologist
will carefully observe your retina and vitreous. Because your eyes
have been dilated, you may need to make arrangements for someone to
drive you home afterwards.
Floaters
and flashes of light become more common as we grow older. While not
all floaters and flashes are serious, you should always have a medical
eye examination by an ophthalmologist to make sure there has been
no damage to your retina.
