what are floaters?
Floaters are little “cobwebs” or specks that float about in your field of vision. They are small, dark, shadowy shapes that can look like spots, thread-like strands, or squiggly lines. They move as your eyes move and seem to dart away when you try to look at them directly. They do not follow your eye movements precisely and usually drift when your eyes stop moving. Most people have floaters and learn to ignore them; they are usually not noticed until they become numerous or more prominent. Floaters can become apparent when looking at something bright, such as white paper or a blue sky.
what causes floaters?
Floaters occur when the vitreous, a jelly-like substance that fills most of the eye, slowly shrinks with age. As the vitreous shrinks, it becomes stringy, and the strands can cast tiny shadows on the retina. These are the floaters you see. In most cases, floaters are part of the natural aging process and simply an annoyance. They can be distracting at first, but eventually tend to “settle” at the bottom of the eye or get smaller, becoming less bothersome. There are however other, more serious causes of floaters such as infection, inflammation (uveitis), haemorrhage (bleeding), retinal tears and retinal detachments. Sometimes, floaters can occur together with flashes of light; seen as a dim flash even when your eyes are closed. This occurs when the vitreous gel bumps, tugs or even tears your retina.
risk factors for floaters?
Floaters are more likely to develop as we get older and are more common in people who are very myopic (short-sighted), have diabetes, trauma to the eye or who have had any eye surgery.
Figure 1. A simulation of how floaters can interfere with your vision
Sometimes floaters and flashes signal a condition that can lead to vision loss where a new onset of floaters may herald retinal disease. The shrinking vitreous can tug on the retina and pull away from it. This event, called a posterior vitreous detachment, is common, and usually doesn’t threaten vision. In a few people, a posterior vitreous detachment causes the retina to tear. Fluid from inside the eye can then seep through the tear and separate the retina from the tissues that nourish it. This separation, called retinal detachment, can lead to permanent vision loss unless treated promptly.
Retinal tears and detachments are painless. Key warning signs include:
New onset of floaters and flashes
Gradual shading of vision from any one side (like a curtain being drawn)
Rapid decline in sharp, central vision. This occurs when the macula, the area of the retina responsible for central vision
If you experience any of these warning signs, call your doctor right away. You will need to see an ophthalmologist for an eye exam as soon as possible. If a tear is detected early, prompt treatment can prevent the retina from detaching.
what happens if i have retinal problem?
Retinal tears can be treated several ways. Your doctor may recommend laser photocoagulation which is usually done in the out-patient clinic. Pinpoints of laser light are used to fuse the retina to the back wall of the eye. This creates a barrier of scar tissue around the retinal tear that stops it from getting bigger. Extreme cold, a procedure called cryopexy, does much the same thing. If you have a retinal detachment, your doctor will explain how urgently you will require retinal surgery and the procedure required.
Figure 2. A view of the inside of your eye showing how bits of the aging vitreous causes the floaters
how are floaters treated?
Anyone who has a sudden onset of floaters needs to be checked by an eye doctor. Once your eye doctor rules out any serious conditions and if the floaters are the only problem, no treatment is usually required as they usually get less troublesome after a few months. 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 desired. A vitrectomy removes the vitreous gel, along with its floating debris, from the eye. The vitreous is replaced with a salt solution. Because the vitreous is mostly water, you will not notice any change between the salt solution and the original vitreous. As with any operation, there are benefits and risks which should be considered, which your eye doctor will explain to you.