The sudden appearance of floaters, or seeing a greater number than usual, can be a sign of a retinal detachment or retinal tear, according to Everyday Health. This medical emergency is more likely if the floaters are accompanied by a loss of peripheral vision or blurred and distorted vision.
A retinal detachment occurs when the retina separates from the supportive tissue and blood vessels at the back of the eye, explains All About Vision. This may occur gradually or suddenly, but in either case, it is painless. The retina must be surgically reattached to its network of supportive tissue in order to restore sight. The sooner surgery occurs, the better the outcome.
In most other cases, the presence of floaters in the visual field is a benign condition, notes WebMD. They may look like dark squiggly lines, black or grey dots, cobwebs, ring-like shapes or knobby, thread-like structures. They tend to move as the eyes move, and when a person tries to focus on them, they usually dart out of sight. Once floaters develop, they don't go away. They tend to become less visible over time, and most people simply learn to cope with them.
Floaters are small specks of the protein collagen that drift through the visual field, states WebMD. They become more pronounced as the gel-like vitreous humor that makes up the back compartment of the eye starts to become more liquid with age. Floaters are most common between the ages of 50 and 75, particularly in very nearsighted individuals and those who have had cataract surgery.