Seeing lights? See the doctor

This is recent. I see a light from the corner of my left eye, as if someone were using a flashlight to get my attention. It is very unnerving. What can I do?

TONY

Los Angeles

Flashing lights are visual disturbances that may represent something totally harmless or may be a symptom of a serious problem. Contact an eye doctor, because that’s the only way you’ll find out for sure what the cause is.

A flash of light in the corner of the eye often is due to changes in the clear jellylike substance that makes up the inside of the eye. As people age, the consistency of this substance changes and it can start to pull on the retina. The condition -- and the flashing light -- usually goes away in a few days or weeks. But in some cases, a retinal detachment can occur, which is very serious.

-- Shari Roan

Shingles vaccine for older adults

Please advise on the effectiveness and advisability of using Zostavax (the shingles vaccination) for a person 72 years old.

DAFNA

Marina del Rey

In October 2006, an advisory panel at the Centers for Disease Control and Prevention recommended that adults 60 and older be vaccinated with Zostavax to help prevent shingles. The recommendation, still under review by the Department of Health and Human Services, is not yet official.

Anyone who has ever had chicken pox (about 90% of adults in America) is at risk for shingles, an often painful disease that causes a blistering rash. The risk increases with age.

In a study of 20,000 people older than 60, the vaccine reduced the incidence of shingles by 51%. Prevention was highest in people ages 60 to 69 and declined with increasing age.

-- Susan Brink

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