Floaters are those weird spots, cobwebs, flies or wiggly worms you might see in your vision on a bright sunny day when looking at the sky or at a light coloured wall. Those shapes are just shadows on the back of your retina. They occur from debris in the vitreous (the middle jelly part of the eye) which form due to the collagen fibres clumping up together over time. They’re more and more common the older you get. However other reasons you might see a floater include retinal tears or detachments, infection, inflammation, or haemorrhages at the back of the eye.
Flashes, also known by the medical term photopsia, are as the name suggests, the sudden flashes of light you might see. It may appear like a camera flash or lightning bolt and you might notice them more at night time. This can be due to either a disturbance along the visual pathway from the eye to the brain or an eye disease which causes the retina to be pulled or tugged.
The causes of either flashes or floaters can range from completely harmless reasons and all the way up to sight-threatening diseases. In 66 percent of patients over 70 years old, the flashes are due to an eye condition called Posterior Vitreous Detachment (PVD). Put in simple terms, the jelly (vitreous) inside your eye is attached to the back of the retina. As you age, the jelly shrinks and breaks off but in the spots where it might be slightly attached – the tugging causes a flash of light.
More serious causes such as retinal tears, retinal detachments and retinal haemorrhages also can result in debris floating within the eye, therefore you might see new floaters to what you’re used to seeing if one of these problems happen.
If you’re experiencing any of the symptoms of flashes or floaters, your local optometrist can investigate the cause. Usually, dilation eye drops are used to open up the pupils which are the windows to your retina. Using a slit lamp biomicroscope a thorough investigation can be done to look around all the way to the far periphery of the retina. With new technology, machines like the OPTOS Ultra-Wide Digital Retinal Scan can give us the same view and a photograph without the eye dilating drops, so we can search the retina for potential eye diseases more quickly and easily.
Treatment largely depends on the cause of the flash or floater. If the cause isn’t serious, your optometrist might just say to monitor them and return if there are any changes. In more extreme cases where the cause is sight-threatening, you may require an urgent referral to an ophthalmologist for same-day treatment with surgery or lasers.