What are floaters?
Floaters look like small specks, dots, circles, lines or cobwebs in your field of vision. While they seem to be in front of your eye, they are floating inside. Floaters are tiny clumps of gel or cells inside the vitreous that fills your eye. What you see are the shadows these clumps cast on your retina.You usually notice floaters when looking at something plain, like a blank wall or a blue sky.As we age, our vitreous starts to thicken or shrink. Sometimes clumps or strands form in the vitreous. If the vitreous pulls away from the back of the eye, it is called posterior vitreous detachment. Floaters usually happen with posterior vitreous detachment. They are not serious, and they tend to fade or go away over time. Severe floaters can be removed by surgery, but this is seldom necessary.You are more likely to get floaters if you:
are nearsighted (you need glasses to see far away)
have had surgery for cataracts
have had inflammation (swelling) inside the eye
What are flashes?
Flashes can look like flashing lights or lightning streaks in your field of vision. Some people compare them to seeing “stars” after being hit on the head. You might see flashes on and off for weeks, or even months. Flashes happen when the vitreous rubs or pulls on your retina.As people age, it is common to see flashes occasionally.Flashes and migraines
Sometimes people have light flashes that look like jagged lines or heat waves. These can appear in one or both eyes and may last up to 20 minutes. This type of flash may be caused by a migraine. A migraine is a spasm of blood vessels in the brain.When you get a headache after these flashes, it is called a “migraine headache.” But sometimes you only see the light flash without having a headache. This is called an “ophthalmic migraine” or “migraine without headache.”
Causes of Floaters and Flashes
As we grow older, it is more common to experience floaters and flashes. When people reach middle age, the vitreous gel may start to 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. This is a common cause of floaters.Floaters and flashes are also caused by posterior vitreous detachment, where the vitreous gel pulls away from the back of the eye. This condition is more common in people who:
Are nearsighted;
Have undergone cataract operations;
Have had YAG laser surgery of the eye;
Have had inflammation (swelling) inside the eye.
Have had an injury to the eye.
The appearance of floaters and flashes may be alarming, especially if they develop very suddenly. To find out if a retinal tear or detachment is occurring, you should call your ophthalmologist right away if you notice the following symptoms, especially if you are over 45 years of age, have had an injury to your eyes or head, or if you have substantial nearsightedness:
A sudden increase in size and number of floaters
A sudden appearance of flashes
Having a shadow or curtain appear in the periphery (side) of your field of vision
Seeing a gray curtain moving across your field of vision
Having a sudden decrease in your vision
Symptoms
Symptoms of vitreous floaters include seeing small specks or clouds moving in your field of vision, or seeing dots, circles, lines or "cobwebs." Symptoms of flashes include seeing flashes of light or seeing "stars."If the vitreous gel shrinks and pulls away from the wall of the eye, the retina can tear. This sometimes causes bleeding inside the eye that may appear as new floaters.A torn retina is always a serious problem, since it can lead to retinal detachment. You should see your ophthalmologist as soon as possible if you suddenly see an increase in the size and number of floaters, and/or you suddenly see flashes of light.Some people experience flashes of light that appear as jagged lines or "heat waves" in both eyes, often lasting 10 to 20 minutes. These are not flashes from the vitreous gel pulling on the retina; instead, these types of flashes are usually caused by a spasm of blood vessels in the brain, called a 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 an ophthalmic migraine, or migraine without headache. Contact your ophthalmologist if you experience these symptoms.If you notice other symptoms, like the loss of side vision, you should see your ophthalmologist.
Diagnosis
Vitreous floaters and flashes become more common as we grow older. However, 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.When an ophthalmologist examines your eyes, your pupils may be dilated (enlarged) with eyedrops. During this painless examination, your ophthalmologist will carefully observe areas of your eye, including the retina and vitreous. If your eyes have been dilated, you will need to make arrangements for someone to drive you home afterward.
Treatment
Most floaters and flashes are not a problem. However, there are times when they can be signs of a serious condition. Here is when you should call an ophthalmologist right away:
you notice a lot of new floaters
you have a lot of flashes
a shadow appears in your peripheral (side) vision
a gray curtain covers part of your vision
These floaters and flashes could be symptoms of a torn or detached retina. This is when the retina pulls away from the back of your eye. This is a serious condition that needs to be treated.Source: American Academy of Ophthalmology. https://www.aao.org/eye-health/diseases/floaters-flashes