Floaters and Flashes



There are many causes of “floaters” in the eye, however the most common cause is when the vitreous, (a gel-like substance that fills about 80 percent of the eye and helps it maintain a round shape), slowly shrinks. As the vitreous shrinks, it becomes somewhat stringy, and the strands can cast tiny shadows on the retina. They can look like little bugs, stars, threads, or cobwebs. These are “floaters”.

In most cases, floaters are part of the natural ageing process and are simply annoying. They can be distracting at first, but eventually tend to “settle” at the bottom of the eye, becoming less bothersome. They usually settle below the line of sight and do not go away completely.

Floaters are more likely to develop as we age and are more common in people who are very short-sighted (myopic), have diabetes, or who have had a cataract operation.

For most people, no treatment is necessary. However, if the vitreous gel pulls tears or holes in the retina, this can be sight-threatening and can lead to blindness without treatment. Retinal holes or tears can be treated by Thermal Laser which reduces the risk of retinal detachment. Anyone who has presented with a sudden increase in the number of floaters in their vision should have this checked as this may indicate a serious problem.

Other causes of floaters include bleeding in the eye (vitreous hemorrhage) inflammation in the eye (uveitis) or uncommonly some forms of eye tumours. On rare occasions, floaters can be so dense and numerous that they significantly affect vision. In these cases, a vitrectomy, a surgical procedure that removes floaters from the vitreous, may be needed.


Flashes are flickers or streaks of light that usually occur in the peripheral vision (up above, down below, or to either side of your central vision).

These often happen when the vitreous gel pulls on the retina. The flashes of light can appear on and off for several weeks or months. They are usually seen at night or in poor lighting. Flashes may also occur in other conditions, such as migraine headaches.

Although most people with flashes and floaters do not have a serious, sight-threatening problem, patients should not take the sudden onset of flashes and floaters lightly, as it may indicate an eye condition that could lead to blindness if untreated. Since there are no any pain receptors in the retina inside the eye, people will not experience any pain or discomfort if this happens. Hence, it is important to note if any of the following occur:

• New flashing lights
• More floaters
• Shadows

A dark or grey shadow, especially from the side, is often the most serious symptom of a retinal detachment.

A careful examination of the retina and vitreous through a dilated pupil is absolutely essential following the onset of “flashes and floaters” because our retina specialists can determine if what people are seeing is harmless, or the symptom of a more serious problem requiring treatment.