The vast majority of people experiencing ‘flashes and floaters’ do not have a serious eye condition and the condition usually settles without any sequelae. However if you experience these symptoms your eyes need to be properly examined.
Flashing lights sometimes occur on their own and floaters can also occur without experiencing flashes. But more often than not they occur in conjunction with each other.
Flashes originate from the retina (film at the back of your eye) and the intermittent flashing light is seen in your side vision and is caused by the jelly like substance (vitreous) pulling occasionally on the retina due to the movement of your eyes. These flashes last only a split second although very occasionally they are sometimes seen as an ‘arc’ of light lasting a little longer. Flashes are more obvious in the dark or in low light conditions.
(Flashes that last 10-30 minutes are not retinal in nature. ‘Flashing’ from visual migraine, where there is usually no headache, lasts much longer than a few seconds and is ‘zig-zag’ in nature or like a ‘kaleidoscope’. This migrainous flashing has nothing to do with the eye, it emanates further along the visual pathway inside the brain. )
Floaters are black dots and/or ‘spiders’ or ‘net-like’ opacities and these can also sometimes occur on their own unaccompanied by flashing lights. These vitreous floaters drift back and forth in front of your vision and often keep moving due to their momentum even when your eye itself has stopped moving.
Flashes are more often than not followed by floaters. In other words the two symptoms occur in conjunction with each other in many cases. If you are over 55 years of age or if you are ‘short sighted’ (myopic) you are more likely to experience these symptoms, although they can occur at any age.
Floaters in the younger age group are often physiological (normal) and in older age groups are due to weakening of the collagen fibres in the vitreous due to advancing years – just like wrinkles in your skin. In both age groups there is a small chance that flashes and/or floaters are due to a serious condition.
Serious conditions associated with flashes and or floaters could be ‘Retinal Detachment’ or inflammatory conditions of your eye such as ‘Uveitis’.
TAKE HOME MESSAGE:
If you experience ‘Flashes’ or ‘Floaters’ or ‘Flashes and Floaters’ then you need to see a Medical Eye Doctor (ophthalmologist or ophthalmic surgeon) at an early date in order to out rule a serious eye condition following which you will probably be given the ‘all clear’.
NB: If you experience these symptoms in association with permanent blurring or loss of vision you need to be examined by an eye doctor immediately.