Your eye is basically a hollow ball filled with water. The largest compartment in the eye is the posterior chamber. The posterior chamber is filled with a fluid, called the vitreous, which is 99% water and 1% protein. The vitreous helps the eye form before birth, but you do not need it. As we age, the vitreous shrinks. This allows the vitreous to lag behind as the eye moves rapidly from side to side. As the eye is moving, the vitreous may pull on the retina, stimulating it and causing a flashing light sensation similar to a flash bulb or the sun setting on the water. If the gel breaks free, debris in the gel may float around the eye, casting shadows on the retina that appear as floaters to the patient. In some patients, the vitreous does not break clean of the retina but instead it tears the retina causing bleeding into the eye or a retinal detachment. If you have symptoms of new floaters, or persistent flashing lights in your eye, you should be examined by a surgical retinal specialist promptly to rule out a retinal tear or retinal detachment.
Vitreous floaters can be distracting or even visually impairing. The biggest risks with floaters is when they are associated with a retinal tear or retinal detachment which can lead to permanent vision loss. However, the symptoms of vitreous floaters generally decrease with time, and become less noticeable without treatment. In the rare case where the symptoms persist and become debilitating, vitrectomy surgery, or removal of the vitreous gel, can be performed. Recent advances in microsurgical techniques have made this procedure much safer, but like all surgical procedures, there are inherent risks.
Other treatments for floaters remain controversial. At this time, laser procedures, eye drops, or eye injections to decrease the floaters are experimental and are generally not covered by insurance. Only a vitrectomy can completely remove the floaters.