Pretty much everyone has seen those weird transparent wormy things occasionally floating across their field of view. They always look a bit unnerving, as though some kind of bug is sitting on your eye. We decided it was time to answer the question: ’what are these things really?’ It turns out they’re called ’muscae volitantes’, which is Latin for ’flying flies’…but they’re actually not flies at all, or any other kind of bug.
Sometimes, against a uniform, bright backgrounds such as a clear sky or a blank computer screen, you might see them floating across your field of vision. But how are you seeing them? Michael Mauser explains the visual phenomenon that is floaters in the following video:
Vitreous humour is a clear, jelly-like substance that fills the space in the middle of the eyeball. The debris casts shadows on to the retina (the light-sensitive tissue lining the back of the eye). If you have floaters, it’s these shadows you’ll see. Floaters can occur as your eyes change with age.
Floaters are usually harmless and don’t significantly affect your vision. However, it’s important you have your eyes checked by an optician regularly (at least once every two years). Larger floaters can be distracting and may make activities involving high levels of concentration, such as reading or driving, difficult. In most cases, they don’t cause significant problems and don’t require treatment.