I just saw a patient who noticed
flashes in his left eye for the past two days and he came in
concerned. This patient happens to have glaucoma that is under
control as well as Diabetes Mellitus, which is under control.
He also has had cataract surgery with implants in both eyes
and sees well.
The floaters and flashes are
very common complaints in all populations of patients at any
age and even those with out eye disease. High myopes meaning
people who are near sighted have more complaints than those
who are not.
The person who notes an onset of
flashes or floaters should have a dilated exam
The infant eye is filled with a
clear jelly like substance called vitreous. The vitreous is
supported by a framework of many fibers that run from one the
retina or inner lining of the eye extending from one wall and
attached across to the other wall. Imagine a tennis ball that
is hollow inside and has millions of crisscrossing fibers from
one wall of the tennis ball across to the other wall and all
of these criss-crossing fibers are encased in a clear jelly
As an infant the jelly is
basically solid and when the eye moves the fibers and jelly
move as one unit. From the day we are born, the jelly or
vitreous becomes more and more liquid and the fibers begin to
move with in the jelly when the eye moves just like seaweed in
a slow current.
The retina tissue is an
extension of your brain tissue and therefore does not have
pain fibers. If I pull your hair you fell pain because of the
nerves in the skin of your scalp. If the fibers pull on your
retina you see a flash of light and so flashes are common in
many people. Most of the time the fibers break loose cleanly
from the retina and then curl on themselves producing this
floating shadow that people call floaters. Also, there may be
some pigment or even a tiny few blood cells released into the
jelly when the fiber breaks loose.
After a time the flashes and
floaters usually go away although some people can always see
The real reason to have your
eyes examined is that in 2% to 5% of people the retina tears
because the fibers do not break away cleanly. The resultant
hole allows fluid to get beneath the retina and pushes it away
from the wall of the eye, hence the term retinal detachment.
The retina needs to be attached to receive nutrients and blood
supply and when it detaches it dies and the vision is
Detached retinas need immediate
surgery that may include in-office laser treatment or it may
be sever enough to require more extensive surgery in the
Everyone having the onset of
flashes or floaters should immediately do what my patient did
and come in for a dilated eye exam.