Floaters are small, cloudy particles of various shapes and sizes floating in the jelly fluid inside the eye called the vitreous. They’re especially noticeable when out in the sun or looking at light backgrounds. They move as your eyes move and may seem to disappear when you try to look at them directly.
They can occur spontaneously, but tend to occur more frequently as you get older. The gel in the eye (vitreous) naturally becomes more liquid and shrinks with time. Sometimes the gel can shrink enough to completely separate from the light sensitive area at the back of the eye (the retina), which can produce a ring shaped floater.
Even though these spots are usually harmless and do not affect vision, they can be signs of more serious problems such as retinal detachment.
You may see a brief flash of light in an arc shape in the periphery of your vision normally in the dark, which can come and go. These are different to the shimmering or zigzag lines that might be part of a migraine.
These usually occur when the gel inside your eye (vitreous) shrinks and pulls on the retina. This will sometime lead to a brief flash.
Constant flashes, especially if associated with a shadow in the corner of the vision, may be a sign of a retinal tear or retinal detachment (where the retina becomes separated from its underlying layer), which is a rare but serious eye condition which requires immediate treatment to prevent permanent vision loss.
Please seek immediate attention at your opticians or local eye casualty department if you develop any of the following symptoms: