In effect, this is a 'mini-stroke' in your eye, says Mr Berghardt. Head to your GP straight away - a full-blown stroke could be on the way,' he says.A persistent fogginess is more likely to be a cataract, which is when the lens of the eye becomes cloudy - again this is more commonly seen in those over 50.'This can be a symptom of multiple sclerosis, but is rare, so speak to a specialist before panicking,' says Mr Berghardt.When we look at something, the information from the eyes stops the brain creating its own pictures, says Brendan Moriarty, a consultant eye surgeon in Altrincham, Cheshire.Flashing lights can also be an early warning for migraines.'Flashing lights that last for 15 to 30 minutes are often symptomatic of ocular migraines, which are headaches that also cause coloured lights usually in both eyes,' he says.'The brain starts to build artificial images from the areas we use every day to process faces, objects, landscapes and colours.' There is no treatment of proven effectiveness for CBS.It usually disappears within 18 months, as experience teaches the brain the hallucinations aren't real.
Your brain interprets this as different colours, says Neil Constantine-Smith, Specsavers optician.This is where you don't produce enough tears or the tear film evaporates too quickly, causing the eyes to dry out and become inflamed. 'With no moisture on your cornea, it can feel as if you're dragging your eyelids over ground glass,' he says.'Dry eye syndrome is increasingly common thanks to the increasing use of air conditioning and computer screens.' If an eye test rules out short-sightedness and the fogginess has appeared suddenly and isn't eased by eye drops, the problem could be related to blood circulation.If the multi-coloured lights last for longer than 30 minutes, it could signify a detached retina.'Unlike ocular migraines, these are almost always in one eye, so put a hand over one eye and see if it's the same on both sides,' he says.