glenn.w.thompson - 2012-11-07 8:16 PM
Kathy,
This is long-winded, but I hope complete.
I'm an ophthalmologist and see this as my patients presenting complaints at least 3 or 4 times each day. As others have said, they are related to the vitreous gel inside the eyeball liquifying with age. Although common and annoying, they can be associated with retinal tears or detachments (some studies say up to 15%; however in my experience it is much lower). This is why I advise anyone with new onset or dramatic changes in their floaters to have a dilated eye exam.
As part of my discussion with patients in the office I specifically tell them that their floaters will be more noticeable when there is little background noise (ie. clear blue sky, plain white movie screen). They rythmic roation involved in swimming may also play a role in causing the floater to move in a repetitive pattern and therefore become more noticeable (maybe I'll look into a research paper!)
There really is no treatment for floaters. Vitrectomy surgery where the entire vitreous gel inside the eye is removed would remove most of the floaters, but is reserved for more severe, potentially blinding diseases such at retinal detachments or hemorrhages inside the eye.
Sorry for the long response, but hope it helps, Glenn
Good info here. Part of why BT is so cool.