FLASHES AND FLOATERS
Don’t be alarmed if you have suddenly become aware of a small black floating object in one of your eyes. These take many forms and are frequently described as appearing like a cobweb, spider, small ring-shaped or hook-shaped object, or small black spots. They move with the eye and can be seen to float past the centre of your vision as you turn your head or eye suddenly. Often, bright flashes of light are experienced in the eye when you first notice the floaters or at times following its onset. Flashes are most commonly noticed at night, but initially may be experienced during the day also.
What causes flashes and floaters?
Most of the eyeball is filled with a clear, jelly-like substance, similar to a raw egg white, called the vitreous body. In children and young adults, this jelly is more solid. With ageing, areas within the jelly begin to liquefy and gradually become fluid. As this natural degeneration proceeds, a stage is reached when the jelly suddenly collapses inward on itself toward the centre of the eye (an acute vitreous detachment). Small strands of condensed jelly become suspended in the mobile fluid and move about in the eye casting a shadow on the retina in the back of the eye, creating the small floating shapes. The jelly has stronger attachments to the retina on the inner wall of the eye in some areas. With eye movement, the jelly wobbles, and may tug on the retina where it is still attached, generating lightning-like flashes. Occasionally, as the jelly collapses away from the wall of the eye, it creates a small tear in the retina due to the pulling. This can then lead to a lifting off of the retina (a retinal detachment). Sometimes, bleeding can occur from a torn blood vessel associated with a tear. While these processes most commonly result from normal ageing in the eye, degeneration of the jelly ocurs far earlier in people who are highly short-sighted or can be precipitated by a blow to the eye.
What is the treatment?
Generally, no treatment is required unless there is a tear or detachment of the retina. A thorough examination of the eye, with the pupil dilated, is made to exclude problems with the retina. If there are persisting flashes, examination may need repeating 6 weeks or so later. The floaters themselves are harmless and will remain in the eye, but usually are not noticed after a few weeks or months. They are more of an annoyance.
Beware: If you experience an increase in the flashes, notice the appearance of a curtain-like area of lost vision or a shower of small black spots, please contact the Clinic promptly on (07) 5470 2400.