What it is
In short: floaters are small shapes that drift across your vision, and flashes are brief streaks of light. Both are often caused by normal ageing changes in the gel inside the eye. But a sudden change can be a sign of a retinal tear, so it needs checking the same day.
Floaters can look like threads, rings, cobwebs or small specks. They are usually shadows cast on the retina (the layer at the back of the eye that senses light) by changes in the vitreous, the clear gel that fills the eye.
With age, the vitreous shrinks and can come away from the retina. This is called a posterior vitreous detachment (PVD). As the gel pulls on the retina, you may see flashes of light. A PVD is a change in the gel. It is not the same as a retinal detachment, where the retina itself lifts away from the tissue beneath it.
Age-related gel changes are a common cause of floaters, but not the only one. Floaters can also come from bleeding, inflammation or a retinal tear. You cannot tell the cause from how a floater looks, so new or changing floaters need checking.
Symptoms
Floaters are easiest to see against a bright, plain background, such as a white wall. They move when your eyes move, and drift away when you try to look at them directly.
Flashes from the vitreous often look like brief streaks of light towards the side of your vision, especially in dim light.
Floaters you have had for a long time, which have been checked and have not changed, are different from a sudden shower of new ones. It helps Dr Chin to know whether one eye or both are affected, and whether you also have blurred vision, a shadow or missing vision. But do not put off getting checked in order to watch your symptoms at home.
When it is urgent
Get your eye checked the same day if you have:
- new floaters or flashes
- a sudden increase in floaters or flashes
- floaters or flashes after an eye injury or an eye operation
Get care straight away if you see a curtain or shadow, or your sight suddenly drops.
Call the clinic at +65 6694 0400. Outside clinic hours, call the 24-hour answering service at +65 6535 8833, or go to a hospital A&E with eye services. A sudden change needs checking the same day, even if your eye does not hurt.
What the assessment involves
Dr Chin will ask when your symptoms started and how they have changed, and about any eye surgery, injuries or other eye conditions. Your vision is checked, and drops widen your pupils so that Dr Chin can examine the vitreous and the retina. The outer edges of the retina need careful checking, because a tear can be far from the centre.
To see the far edges, Dr Chin may press gently around the eye. If blood or cloudiness blocks the view, an ultrasound scan can help. An OCT scan may be used to show how the gel sits against the centre of the retina. Each test answers a different question, and scans do not replace the examination of the retina.
The drops take 20 to 30 minutes to work. They blur your sight and make your eyes sensitive to light for a few hours. Allow about 90 minutes to two hours for the visit, and arrange for someone to drive you home.
Treatment options
A PVD with no other problem
If the examination shows a PVD with no other problem, regular checks are usually all that is needed. The gel does not need to be reattached. The aim of the examination is to look for problems linked to the PVD, not to treat every floater.
A tear or another cause
- A retinal tear may need laser or freezing treatment.
- A retinal detachment usually needs surgery.
- If bleeding or inflammation is the cause, that condition is treated.
Treating a tear does not remove the floaters you already have.
Floaters that do not settle
Some people with floaters that do not settle try a dietary supplement called VitroCap N. It contains L-lysine, vitamin C, zinc and plant extracts. It has been studied in a small trial, and the evidence is still limited. Ask Dr Chin whether it could suit you.
If floaters do not settle and get in the way of daily life a lot, an operation to remove the gel (vitrectomy) may be discussed separately. The decision depends on your symptoms and the examination, weighed against the risks. These include cataract, retinal tears or detachment, swelling and loss of vision.
Recovery and follow-up
Floaters often become less noticeable over time as the brain learns to ignore them, but they can persist. After a recent PVD, you may be asked to come back for another check, because the gel can keep separating. The timing depends on what was found, your symptoms and your risk factors.
Get checked again if floaters or flashes increase, or a shadow or reduced sight appears, even after a reassuring examination. Keep your follow-up appointments. If you have a procedure, you will get separate instructions about drops, activities and which symptoms to report.
Related articles
- Floaters and flashes: when should I be worried?
- Retinal tears and laser treatment
- Retinal detachment and tears
Sources
- National Eye Institute: Floaters
- Ankamah et al., Translational Vision Science & Technology (2021): Micronutrient supplement trial for floaters
- American Society of Retina Specialists: Posterior vitreous detachment
- American Society of Retina Specialists: Vitrectomy for floaters
- Singapore National Eye Centre: Your clinic visit