What are floaters?

Floaters are relatively transparent, vague, usually curves objects that are seen best when looking at a white piece of paper, blue sky, light coloured ceiling, or wall. They sometimes look like cobwebs, worms, rings, dots, or specks. Eye movement makes floaters more visible as they swirl about like seaweed in the ocean surf.

What is the most common cause of floaters?

They are usually cause by a clumping of pre-existing vitreous fibres in the eye. Therefore, vision care professionals usually refer to them as vitreous condensations.

What are some of the other causes?

Some floaters are red blood cells or blood clots on the surface of the retina or floating in the vitreous. Such blood cells may occur with some retinal tears but do not necessarily indicate a tear. Occasionally, the vitreous can pull on a blood vessel on the surface of the retina and cause bleeding without causing a tear of the retina. Vascular disorders such as diabetic retinopathy and vein occlusion frequently result in bleeding inside the eye.

Rarely, floaters may be inflammatory in origin. Diseases such as pars planitis and uveitis can cause the formation of clumps of white blood cells (cells that the body produces when there is inflammation). 

Floaters can also appear after a YAG laser capsule opening procedure (capsulotomy). After almost 50% of cataract surgery procedures that involve the implantation of intra-ocular lenses, the layer of tissue behind this lens becomes cloudy, causing a decrease in vision. The YAG laser capsule opening procedure is performed in these cases to place an opening in this "lens capsule", which usually results in better vision, but can also cause floaters.

Can floaters cause total blindness?

Floaters do not cause total blindness, only a slight blockage of the vision at worst. Floaters are usually not detectable by visual testing unless they are very severe. Importantly, floaters can be related to retinal detachment or a variety of vascular conditions such as diabetic retinopathy, which can result in blindness if not treated. It is important to have any new incidence of floaters checked by your optometrist.