Roanoke Times Copyright (c) 1995, Landmark Communications, Inc. DATE: TUESDAY, October 10, 1995 TAG: 9510100099 SECTION: NATL/INT PAGE: C4 EDITION: METRO SOURCE: ASSOCIATED PRESS DATELINE: ORLANDO, FLA LENGTH: Medium
Overnight use of contact lenses has been associated with an increased risk of infections, the worst of which can lead to blindness. Disposable lenses were introduced with the idea that they would reduce the opportunities for bacterial contamination, because they wouldn't be handled as much and wouldn't be stored in solutions that could harbor germs.
``That idea was simple, easy and wrong,'' said Dr. H. Dwight Cavanagh, a professor of ophthalmology at the University of Texas Southwestern Medical Center at Dallas.
Speaking at a seminar sponsored by Research to Prevent Blindness, a voluntary organization, Cavanagh said: ``The implication now in mass marketing of disposable lenses is that these things are safe - game over, time out, totally safe. That's not true.''
He stressed that the risk of infections with any contact lens is small. As many as 40 million people in the United States wear contact lenses, but lenses account for only about half of the 27,000 corneal infections seen yearly in the country, he said.
Nearly all American contact-lens wearers wear soft lenses, and about 4 million to 5 million Americans wear disposable lenses, Cavanagh said. Those who wear their lenses overnight have a risk of eye infection 10 to 15 times that of users who insert and remove their lenses daily, he said.
That contradicts the belief of some that the problem is that patients aren't using their lenses properly, said Dr. Oliver Schein, an ophthalmologist at Johns Hopkins University in Baltimore.
Tim Comstock of Bausch & Lomb, one of the nation's largest manufacturers of contact lenses, said the company had not made any special claims for the safety of disposable lenses other than to say they are cleaner and fresher than reusable lenses.
Cavanagh's most recent research has shown that the increased risk occurs because extended-wear soft contact lenses, disposable or not, do not allow enough oxygen to reach the surface of the cornea. That damages the cornea, giving bacteria an opportunity to invade, he said.
by CNB