Floaters look like small, dark spots or strands that appear to float in front of your eyes. They are very common and normally harmless. They are more common if you are short sighted or as you get older.
Some people report flashes of light. This can be due to movement of the gel inside the eye.
Very occasionally, flashes or an increase in floaters can indicate retinal detachment, which needs immediate treatment.
Symptoms that require immediate attention are:
Some people are born with floaters, other floaters occur as you get older when the gel in the eye, the vitreous humour, naturally shrinks. The collapse of the vitreous gel can pull on your retina causing flashes of light. If you notice these symptoms, you should contact your optometrist immediately.
Some people see flashes of light in front of one of their eyes, like small sparkles, lightening or fireworks. They tend to be in the extreme corners of your vision, come and go and don’t obscure any part of your vision. The flashes don’t last for a defined length of time and you may notice them more if you go from a light to dark environment. They may continue for several months.
These are different to the shimmering or zig-zag lines that are often caused by a migraine. Migraine shimmers are a flickering of light, often on only one side of your vision which then expand to the outside of your vision with a sort of jagged pattern, often obscuring part of your vision (left or right side). The shimmers usually go away after 10-20 minutes and may be followed by a headache.
These are people who: