Flashes And Floaters

Flashes And Floaters

Alternate Names

  • vitreous opacities
  • spots in front of the eye
  • light flashes
  • Normal eye


Floaters are spots or lines that seem to float in a person's field of vision. The affected person may see these accompanied by flashes of light coming from the side of the eye.

What is going on in the body?

The clear jelly-like material that fills the eyeball is called the vitreous gel. This is a thick liquid with pieces of protein spread apart like a latticework through which you can see. People in their 30s or even younger, if nearsighted, will see smaller dark spots drifting in their vision when looking at a bright surface. This happens because pieces of the protein collapse onto each other. When light enters the eye, it hits these small particles, casting a shadow on the retina. These are normal.
With normal aging, this gel may start to thicken and shrink. This may cause the gel to pull away from the internal lining of the eye. This condition is known as posterior vitreous detachment. While some parts of the gel inside the eye thicken, other parts of the gel will liquefy.
When floaters occur, a person will sometimes have quick, arc-shaped flashes of light out of the corner of the eye. These are often described as lightning flashes. Flashes may occur off and on for several weeks or even months. However, they usually disappear with time. Floaters can also follow inflammation or bleeding inside the eye.


What are the causes and risks of the condition?

Floaters develop as a result of changes in the make up of the vitreous gel inside the eye. The gel may pull on or rub against the retina as the eye moves. The retina is the "film" on the back of the eye that helps transmit the things we see to the brain. When the gel pulls or rubs the retina, flashing lights or lightning streaks may occur in the person's vision. Flashes of light may also be a symptom of migraine headache. A person who experiences light flashes should be evaluated for migraines.


What can be done to prevent the condition?

Most cases of floaters cannot be prevented. They are a common and almost normal part of aging.


How is the condition diagnosed?

If a person notices a new floater accompanied by light flashes, he or she should be checked by an eye care professional. He or she puts drops in the eye to dilate or widen the pupil and carefully observe the retina and vitreous. It is important to rule out the possibility of a torn retina.
Retinal tears can develop 10% of the time when floaters are accompanied by bright flashes of light of a second's duration as the shrinking vitreous pulls away from the retina..Flashing lights lasting fifteen to twenty minutes are usually due to migraine or vascular problems in the brain and require medical evaluation by a primary healthcare professional.

Long Term Effects

What are the long-term effects of the condition?

Floaters and flashes of light themselves cause no long-term effects. Flashes of light usually go away within a few weeks. Floaters can sometimes be noticed for years, but the brain usually learns to ignore the floaters and they become much less noticeable with time. An examination is important, however, to rule out other more serious causes.
For example, if undetected, a tear in the retina can sometimes lead to permanent loss of vision. Fluid can leak through the hole and accumulate under the retina, causing the retina to detach. When this happens, surgery is needed to correct the problem. However, if a retinal tear is found early, it can be sealed using a laser. This reduces the risk of detachment.

Other Risks

What are the risks to others?

This condition is not contagious and poses no risk to others.


What are the treatments for the condition?

Treatment is not needed or helpful if the retina is free of bleeding, tears and weak spots. Treatment is needed if a tear is found in the retina. This is most commonly repaired with a special argon laser by an eye doctor. In some cases, surgery may be needed to reattach the retina. 85% of retinal tears and detachments can be successfully treated. If the entire retina is detached before surgical intervention, some permanent vision loss occurs.

Side Effects

What are the side effects of the treatments?

Laser treatment may irritate the eye or very rarely result in minor vision loss. Eye surgery may cause bleeding, infection or a reaction to any pain medications used. Vision loss is also possible, though rare.

After Treatment

What happens after treatment for the condition?

After an eye exam, the pupils often stay dilated for a few hours from the eye drops given. This makes the eyes sensitive to bright light and often causes blurry vision for things up close. This effect goes away within a few hours and is never permanent.
For regular floaters and flashes of light, no treatment is given and symptoms gradually wane over time. Years later, people may still notice their floaters when tired or reading for long periods of time. After laser treatment or surgery, at least one or two follow up eye exams are done. After that, no further treatment may be needed.


How is the condition monitored?

If a new group of floaters suddenly develops, an individual must be re-examined. This is necessary even if the person has had small floaters for years. Usually the floaters will appear suddenly in only one eye. An eye care professional performs this exam with the pupils dilated.

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