Floaters are specks of various shapes and sizes that float in and out of your vision.  They might seem quite alarming to you the first time you notice them.  They can occur in one or both eyes, and to different extents in each eye.  Floaters can assume different shapes, including cobwebs, threads, dots, or little bugs.  They can move in your field of vision as your eyes move.  They also are more noticeable against a light or white-colored background, as for example when looking at a white piece of paper or even a cloud-filled sky.  They can occur at any age, but usually are more noticeable in older persons.  www.nei.nih.gov/health/floaters

Sometimes floaters can be accompanied by flashes.  Flashes are streaks of light that resemble a flash from a camera or from a strobe light.  Flashes can occur in one or both eyes.  It can be difficult to establish which eye is experiencing the flashes unless one eye is covered to ascertain the extent of the flashes. 

Floaters and flashes can occur as a result of changes in one of the structures of the eye, the vitreous cavity.   The vitreous is a gel – like structure that fills the back of the eye and provides nourishment to the retina, which is the structure in the back of the eye that is analogous in function to the film in a camera.  Vitreous floaters occur as a result of clumping of the vitreous gel.  As we get older, the vitreous gel separates from the back of the eye, the retina.  This is part of the normal aging process of the eye, and could result in the appearance of a larger cobweb-like floater.  Sometimes the action of the vitreous gel separating from the back of the eye and tugging on the retina results in flashes. When the vitreous separates from the retina, this is called a vitreous separation or vitreous detachment.  It occurs as a result of normal aging of the eye, and is not the same as a retinal detachment, which is not part of the normal aging of the eye and is a potentially serious and sight-threatening condition.

Some people do not experience the symptoms of floaters and/or flashes.  However, if you do experience the new onset of floaters and/or flashes, you should seek care immediately from an eye care provider.  Usually, the new onset of flashes and floaters herald the development of a vitreous detachment, but less often they could signal a retinal detachment, which is a far more serious condition.  The only way to detect a retinal and potentially sight-threatening condition is with a dilated eye exam, in which drops are placed in your eyes to dilate your pupils and facilitate examination of the retina.    It is not uncommon for your eye care professional to request that you return for several follow-up visits to dilate your eyes and ascertain the health of your retina after the new onset of flashes and/or floaters. 

After a vitreous detachment, flashes usually fade away.  Floaters may persist, but usually become less noticeable and bothersome.  Flashes and floaters resulting from a vitreous detachment are harmless.  However, if you should notice a change in floaters, the new onset of floaters or flashes, or a distortion or curtain-like obstruction of your vision, seek care immediately.