Why am I seeing floaters and should I be worried?Friday, June 14th, 2019, 2:37 pm
Picture this: you’re carrying about your usual business of the day and all of a sudden you see a black spider in the corner of your eye. You’re suddenly frightened but it seems you’re the only person that can see it. You turn and it moves with your eyes. It drifts in the corner of your eye for a few seconds and then disappears. This is called a floater. Floaters can appear clear or white instead of dark and can also appear as spots, strands, cobwebs or shadows. They are especially noticeable when focusing on a blank surface such as a wall or a clear sky. Floaters move as your eyes move and drift slowly when your eyes stop moving. You may only see one floater or many, all appearing the same or in different shapes, seeing them very often or once in a blue moon. The point is, floaters appear differently in every individual, are very common and generally not a cause for concern.
Although it appears as if the floater you’re seeing is in front of your eye, it is actually floating inside in the part of your eye called the vitreous humour. The vitreous humour is the clear, gel-like substance that fills the posterior two thirds of your eye and lies directly in front of the retina. After light enters your eye through the cornea and passes through the lens, the vitreous humour provides a pathway for light to reach the retina where visual information is processed and sent to the brain via the optic nerve. As we age, our vitreous humour shrinks and becomes thread-like. As these strands of vitreous float freely within the eye, they cast shadows on the retina and appear as dark spots in our vision. Therefore, what you’re seeing is not actually the floater itself but the shadow it is casting onto your retina. Most often, floaters occur as a natural part of aging and therefore are more common in people over 50. Floaters also appear more often in people who are near-sighted, who have had cataract surgery or an eye injury and people who have diabetes. Most people are not bothered by their floaters and learn to ignore them over time. However, some may find that if the floaters increase in number and/or size and appear more frequently, they interfere with vision or are simply bothersome.
In certain cases where new floaters appear suddenly and in large numbers, your eyes may have undergone what is called a posterior vitreous detachment. A posterior vitreous detachment occurs when a section of the vitreous humor, with its many fine fibers, is pulled away from the retina all at once rather than gradually causing many new floaters to appear suddenly. You may also experience seeing flashes of light. A distinguishing feature of posterior vitreous detachment is that the floater is fixed as it moves with your eye. Although it sounds very similar to the much-feared medical emergency called a retinal detachment, you can rest reassured that a vitreous detachment is very common and not dangerous to your vision.
You’re probably thinking, how do I know whether I’ve had a retinal detachment or a vitreous detachment when both conditions cause the sudden appearance of floaters? The difference is that a retinal detachment will present with other symptoms, particularly peripheral vision loss. It may also appear as if a dark veil or curtain is coming across your vision. If these symptoms came on suddenly after an injury to your eye, this may also point towards a retinal detachment. As this is a medical emergency, we recommend that you go to the emergency department immediately if you experience these symptoms. If left untreated, you could suffer permanent vision impairment within hours to days or even blindness in the affected eye.
If your floaters aren’t a sign of retinal damage and are simply a result of the natural breakdown of the vitreous, unfortunately, there is nothing clinically that can be done to treat floaters. A vitreous detachment is a once in a lifetime event and the vitreous cannot be reattached. 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 temporarily remove them from your field of vision by moving your eyes up and down to redirect the floaters from your central vision or wearing dark glasses. If the floaters are so dense and numerous that they impede your vision, your doctor may recommend a surgical procedure called a vitrectomy, although this is quite rare.