‘Floaters’ in the Eyes Can Have Sudden Onset
Maintaining Your
Health on Mackinac
By Yvan Silva, M.D.

It happens suddenly, and when it does the first time, it can certainly cause great alarm. You begin to see specks, tiny insects, lighted spots, or cobweb-like formations move across your field of vision. It may occur when you rub your eyes, or strain them reading or watching television, when you change positions from sitting to standing, or just out of the blue. You may feel a pop in one of your eyes and the floaters may just occur in one eye. They may occur in both, and they may be transient and disappear in a few minutes. Floaters can change from this pattern into a blurriness that can persist overnight.

The eye consists of an anterior aqueous chamber, between the lens and the cornea, and a posterior chamber in back, between the lens and the retina. It is filled with vitreous, a sticky, gel-like substance that is 99 percent water. This vitreous chamber makes up four-fifths of the eye, giving the eye its shape and working as a shock absorber. The vitreous material is composed of a protein in strands, called collagen, and other molecules that are acidic. As we age, the composition of the gel begins to change, the molecules break down and allow tiny pockets of water to collect, while the transparent strands of protein begin to become opaque, into wisp-like formations and fine fibrils.

Most adults experience floaters at some time or another. The suspension of clumps of protein and water pockets wander in the vitreous and, as light traverses the eye, they cast shadows on the retina, the eye’s screen that forms and sends images to the brain. The entire vitreous body, as it is also called, is encased in a thin envelope and the onset of floaters is most often due to detachment of the back of the envelope. In 85 percent of patients with their first onset of floaters, this detachment is of no major consequence, but when they occur suddenly and persist, immediate medical attention is most important. While floaters are common, ophthalmologists warn that sudden onset of tiny floaters with flashes of light are the ones that should be evaluated medically. The second type is much less common and the floaters are caused by tiny specks of blood resulting from tears in the retina or from damage from diabetes. Generally the brain gets used to interpreting the floaters or they migrate from view, causing no serious disturbance of vision.

Retinal detachment, as it is called, is a third and more difficult problem. This results from degenerating vitreous fluid getting interposed between the skin of the vitreous and the retina, separating the two and causing impairment of vision. As it tears, a tissue fragment becomes attached to the separated vitreous envelope, usually near the optic nerve, obscuring central vision. Vision loss depends on the degree of separation. These detachments occur with increasing frequency with aging. They occur in about 10 percent or less of the people under 50, but 60 percent of the people over 70. Ten to 15 percent of these cases require urgent treatment, either with laser or with eye surgery.

Although they rank highly on the lists of patients’ eye complaints, most eye physicians believe that floaters are best left alone; laser surgery is less drastic than eye surgery on the vitreous chamber itself. People who suffer from floaters should always notify their health care specialists, especially when they’re fitted for corrective lenses.

A new drug may pave the way to managing floaters more effectively. Vitrase, a natural enzyme obtained from animals, is said to help liquefy the vitreous contents, but it’s just a beginning. There are issues to be resolved, such as dosing and experience to be gained with use before it, and further advances, make floaters a problem of the past.

Dr. Silva is a professor of surgery at Wayne State University and a resident of Woodbluff on Mackinac Island.