Eye Floaters & Eye Flashes
What are Floaters?
You may experience tiny dark spots in your vision that drift in your peripheral vision. They can be described as spots, flecks or cobwebs and can often be irritating. They can be especially noticeable when focusing on a light blank surface such as a wall or a bright sky. Floaters are common and normally no cause for concern.
What causes floaters?
Eighty percent of the eyes volume consists of a gel-like fluid called vitreous humor. As we age, the vitreous shrinks and becomes thread-like. As these strands of vitreous float freely within the eye, they cast shadows on the retina, the part of the eye responsible for processing light. These shadows appear as dark spots in your vision that float around in your vision.
Should I be concerned?
Most often floaters occur as a natural part of ageing. They become most noticeable in individuals between 50 and 75 who are near sighted or have had cataract surgery. Floaters that are consistent in number and do not change dramatically over time are rarely cause for concern, however there are medical conditions that can cause an increase in floaters and in this case should be examined by an ophthalmologist immediately. You should seek treatment from your doctor if at any time you notice:
- a sudden increase in floaters
- floaters accompanied by a flashing light
- sudden onset vision loss
- a dark veil or curtain over your vision
- eye pain associated with an increase in floaters
- floaters after any eye injury or trauma
Can floaters be treated?
If the floaters are as a result of natural breaking down of the vitreous, unfortunately there is nothing clinically that can be done to treat floaters. Over time, the brain will ‘ignore’ these floaters and they will become less noticeable in your sight. If they are bothersome, it may be possible to remove them from your line of vision by moving your eyes up and down to redirect the floaters from your central vision.
If these floaters are so dense and numerous that they impede your vision, your doctor may recommend a procedure called a vitrectomy. During this procedure, the vitreous and any debris are removed and replaced with a saline solution. There are risks associated with this procedure including retinal detachments, retinal tears and cataracts. Although these risks are not extremely common, they can result in vision loss. For that reason most physicians will only perform this procedure if the vision is greatly disturbed from the amount and density of the floaters.
What are flashes/flashing lights?
Flashing lights are described as a flickering or a blinking light visible in the vision even when eyes are closed. These flashes of light might be short-lived or continue indefinitely.
What causes flashing lights?
When light enters the eye it stimulates the retina which triggers a response that the optic nerve transmits to the brain. The brain then interprets this impulse as light or an image. When the vitreous pulls from the walls of the retina, or the retina detaches or tears, the impulse is received as a flicker of light.
Flashing lights described as wiggly lines, kaleidoscopic or “heat waves” can also be experienced when there is a spasm of blood vessels in the brain known as a migraine aura. Determining what the cause behind the flashing lights should be evaluated by a physician.
Should I be concerned?
Most of the time the vitreous separates from the retina without causing any problems. However, if you begin to experience any visible signs as mentioned above, you should seek immediate care from your ophthalmologist or emergency room.