Floaters, Flashes & Retinal Tears

Floaters

Retinal Detachment

Older people often notice occasional spots or opaque flecks drifting across their line of vision, particularly when they are looking at a page of a book, a computer screen, or a solid, light background. These floaters are tiny clusters of cells or gel in the vitreous cavity, where the clear jelly-like substance called vitreous humor fills your eyeball. What you actually see is the shadow these little clumps cast on the retina. In some cases, the vitreous gel may detach from the retina, causing more floaters, an event called posterior vitreous detachment.

About 25% of people have these vitreous detachments and floaters by their 60s, and 65% by their 80s. Floaters also appear more often in people who are nearsighted or have had cataract surgery. These phenomena are usually nothing more than an annoyance and often dissipate on their own. If they occur suddenly, however, consult an ophthalmologist. Certain eye diseases or injuries can cause them. Floaters can also be small drops of blood from a torn retinal vessel. Less commonly, new floaters are the sign of a retinal tear, which should be evaluated.

Once floaters have been checked and declared harmless, one of three things may happen. The floater may disappear as it breaks apart or settles; the floater may become less noticeable with time; or it may stay and become bothersome. Floaters can be removed, but the surgical risk is greater than the floater itself. If floaters become a nuisance to central vision, moving the eye up and down or left and right may shift the floaters and provide temporary relief.

Flashes

Seeing shooting stars — a phenomenon called photopsia — is not unusual as people age. Solitary flashes appear as sparks or minuscule strands of light, almost like streaks of lightning across the sky. They occur when the vitreous gel bumps, rubs, or tugs against the retina. Generally harmless, they require no treatment. In rare cases, they may be a sign of more severe retinal complications. If their appearance is sudden or accompanied by a shower of floaters or a loss of peripheral vision, see your ophthalmologist. These flashes of light are different from the flashing or zigzag lights that may precede migraine headache, which some people experience simultaneously in both eyes, typically for as long as 20 minutes, but sometimes for an hour or even longer.

Retinal tear or detachment

Occasionally, floaters and flashes can be a sign of something more serious: a retinal tear or retinal detachment. In a retinal tear, the vitreous gel pulls on the retina with enough force to tear the retina. Fluid from inside the eye may enter through this tear and separate the retina from underlying tissues that nourish it. Separation of the retina from the back of the eye is called a retinal detachment (see picture). People who are middle-aged and older are the most likely to experience this problem. Nearsightedness increases the chances for detachment, as do cataract removal and eye injuries.

Retinal detachment is a serious condition and can lead to a permanent loss of vision. If you suspect one, contact your ophthalmologist immediately; if you cannot reach your own doctor, go to an emergency room for evaluation. If a tear is caught early, treatment may prevent a retinal detachment. When not treated, the condition may worsen until the retina separates completely from the inner wall of the eye, remaining connected only at the optic nerve in the back of the eye and the ciliary body in the front of the eye. The worst cases cause blindness.

From:everydayhealth