A floater is small opacity that occurs either centrally or off-center in one or both eyes.
It may take the shape of small dots, lines or look like a spider web. They can appear suddenly and can be quite alarming. They may occur spontaneously, after cataract surgery, or eye injury. They may move around with eye movements. Sometimes they can occur in association with a brief flash of light lasting less than a second. The floater is most often caused by the gel in the back of the eye (vitreous), undergoing a normal change called syneresis. The vitreous can tug on the retina and cause a hole which can lead to a serious condition called retinal detachment. It is very important that you make an appointment to see Dr. Matzkin if you experience a floater.
Video courtesy of the American Academy of Ophthalmology