Seeing Lights

WHEN TO SEE YOUR DOCTOR

* You see "flashes of light" after you've been hit on the head or hit in the eye and they don't go away within a few seconds.

* You see flashes of light off and on for more than 20 minutes and you also feel faint.

* You have a condition or disease that predisposes you to eye problems, for example, previous eye injury, diabetes or high blood pressure.

* You also see a large number of previously unnoticed spots in your field of vision.

What Your Symptom Is Telling You

If you've ever been stunned by a smack on the head, you probably know what it's like to see stars or flashing lights.

But what if you're seeing lights that shouldn't be there and you haven't been anywhere near a fist or an errant object? It most likely means that the gel-like substance in your eye called vitreous fluid is literally rubbing your eye the wrong way.

Vitreous fluid is what gives the eyeball its shape. If the gel rubs or pulls on the retina—the thin, light-sensitive membrane in the back of your eyeball that allows you to see—it can distort the image you're focusing on, creating the illusion that you're seeing flashing lights or lightning streaks in front of your eyes for a brief period.

One of the most obvious and serious causes is a tear in the retina, which can happen for many reasons, from a smack on the eye to perhaps a vigorous sneeze. The other really serious possibility is a retinal artery occlusion—a tiny clot in the central retinal artery. Flashing light symptoms should be checked by an ophthalmologist to rule out these serious possibilities.

People who suffer from migraine headaches commonly see flashes of light. In fact, it's often the symptom that a migraine attack is coming on.

But flashes of light can be a symptom that just about everybody will experience at some time in their life. Seeing flashes of light can be one of the many annoyances that go along with an aging body, says George L. White, Jr., Ph.D., ophthalmic researcher with the Center for Community Health at the University of Southern Mississippi in Hattiesburg. These symptoms might occur at any time but are usually experienced after the age of 40. You should get concerned if flashes of light begin to get more frequent or worsen in intensity or if they are associated with other symptoms such as vision loss, headache or dizziness, says Dr. White.

Symptom Relief

Here's what doctors say you should—or shouldn't—do for those flashing lights.

Use your common sense. If you've been hit on the head or eye and see stars that won't go away, you should see your doctor immediately. You could have a tear to the retina that needs immediate medical attention. Retinas can be repaired with a laser or eryosurgery (cold surgery), often on an outpatient basis, says Dr. White.

Treat the headache. If you suffer from migraines, you probably already know that flashes of light are the symptoms signaling the head pain soon to come. What you may not know, though, is that this symptom can also help you head off the headache. Doctors call these flashes of light the migraine aura. The aura lasts for about 20 minutes and is not painful. What works to stop a headache varies among individuals, but some people report success with relaxation techniques and medications. (For other ways to ward off a migraine, see Headaches on page 234.)

Sit back and enjoy the show. If your doctor tells you that your light show is nothing more than a symptom of aging, there is not really anything you can do about it, says Dr. White. Nor should you be concerned about it.