Floaters, Light Flashes and Vitreous Detachment
What is vitreous detachment?
Most of the eye's interior is filled with vitreous, a gel-like substance that helps the eye maintain a round shape. There are millions of fine fibers intertwined within the vitreous that are attached to the surface of the retina, the eye's light-sensitive tissue. As we age, the vitreous slowly shrinks, and these fine fibers pull on the retinal surface. Usually the fibers break, allowing the vitreous to separate and shrink from the retina. This is a vitreous detachment.
In most cases, a vitreous detachment, also known as a posterior vitreous detachment, is not sight-threatening and requires no treatment. This is NOT a retinal detachment.
Who is at risk for vitreous detachment?
A vitreous detachment is a common condition that usually affects people over age 50, and is very common after age 80. People who are nearsighted are also at increased risk. Those who have a vitreous detachment in one eye are likely to have one in the other, although it may not happen until years later.
What are the symptoms of vitreous detachment?
Symptoms of vitreous detachment could be:
- Floaters
- Flashes of light
As the vitreous shrinks, it becomes somewhat stringy, and the strands can cast tiny shadows on the retina that you may notice as floaters, which appear as little “cobwebs” or specks that seem to float about in your field of vision. If you try to look at these shadows they appear to quickly dart of the way.
One symptom of a vitreous detachment is a small but sudden increase in the number of new floaters. This increase in floaters may be accompanied by flashes of light (lightning streaks) in your peripheral, or side, vision. In most cases, either you will not notice a vitreous detachment, or you will find it merely annoying because of the increase in floaters.
How is vitreous detachment detected?
The only way to diagnose the cause of the problem is by a comprehensive dilated eye examination. If the vitreous detachment has led to a macular hole or detached retina, early treatment can help prevent loss of vision.
How are floaters treated?
For people who have floaters that are simply annoying, no treatment recommended.
What is retinal detachment?
The retina is the light-sensitive layer of tissue that lines the inside of the eye and sends visual messages through the optic nerve to the brain. When the retina detaches, it is lifted or pulled from its normal position. If not promptly treated, retinal detachment can cause permanent vision loss.
In some cases there may be small areas of the retina that are torn. These areas, called retinal tears or retinal breaks, can lead to retinal detachment.
How are tear/holes or retinal detachment treated?
Small holes and tears are treated with laser surgery. The procedure is usually performed in the doctor's office or in hospital. During laser surgery tiny burns are made around the hole to “weld” the retina back into place.
Retinal detachments are treated with surgery that may require the patient to stay in the hospital. In some cases a scleral buckle, a tiny synthetic band, is attached to the outside of the eyeball to gently push the wall of the eye against the detached retina. If necessary, a vitrectomy may also be performed. During a vitrectomy, the doctor makes a tiny incision in the sclera (white of the eye). Gas is often injected into the eye to replace the vitreous and reattach the retina; the gas pushes the retina back against the wall of the eye. With all of these procedures, either laser or cryopexy is used to “weld” the retina back in place.
With modern therapy, over 90 percent of those with a retinal detachment can be successfully treated, although sometimes a second treatment is needed.
However, the visual outcome is not always predictable. The final visual may eventually be lost. Visual results are best if the retinal detachment is repaired before the macula (the center region of the retina responsible for fine, detailed vision) detaches. That is why it is important to contact an eye care professional immediately if you see a sudden or gradual increase in the number of floaters and/or light flashes, or dark curtain over the field of vision.