Got Floaters?

Often patients either complain of or casually mention that they see little floating spots in front of their eyes.  They are often described as worms, dust, spiders, gnats, cobwebs, or ghosts (okay, no one has ever called them ghosts to me but it would be interesting).  But why do we see them?

If you have ever put your hand in front of a beam of light, you’ve seen the shadow it makes on the wall.  Now let’s think of light entering the eye.  Anything in the path of the light will create a shadow on the retina (or inside wall of the eye).  So “floaters” are actually inside of the eye and creating a shadow on the retina.  But how do they get there?

The eye is filled with a gel-like substance called vitreous humor. It is common for the collagen fibers that make up the vitreous to clump together or change shape.  We see these as a few strings (or worms, floaters, etc.) that usually come and go and for the most part are not too bothersome or noticeable. 

But, as part of the normal aging process, this vitreous humor becomes more liquid and begins to shrink so that it no longer completely fills the space it originally did. As the gel shrinks, it pulls away from the retina and this event is called a posterior vitreous detachment or PVD.  It is usually signified by new larger floaters and even sometimes flashes of light.  In most cases, these new visual changes are annoying and concerning for a period of time but eventually go away without causing any further problems. 

However, as the vitreous pulls away, there is a possibility that it will tear the retina or cause one of the blood vessels of the retina to hemorrhage. A retinal tear, if detected early, can often be treated with lasers to reinforce the retina and prevent a subsequent retinal detachment.  It is important to not ignore any new floaters or flashes of light and always have them checked out to determine if they are being caused by something usually benign like a PVD or something more serious like a retinal tear or detachment.