What causes those black flecks in eye?

As people age, the jelly-like substance that makes up the eyeball begins to dissolve and break down. This leads to tiny pieces of vitreous breaking loose - these are the 'floaters' you see.

People who are short-sighted are particularly prone as the jelly in their eye is already stretched and under strain, explains Ken Nischal, head of ophthalmology at the Great Ormond Street Hospital in Britain, reports the Daily Mail.

Floaters are usually harmless. They may go away on their own after a few months but are usually permanent. Persistent floaters which disturb the vision can be treated by a procedure called vitrectomy. This replaces some or all of the vitreous humour with a ­silicone oil or gas to restore the natural pressure. If there is a rapid onset of floaters, medical help should be sought.