WEDNESDAY, April 10, 2002 (HealthDayNews) -- American researchers are working on a new way to repair detached retinas.
They've developed a magnetic fluid that pushes damaged retinas back into place -- a technique they say could prevent blindness in thousands of people who can't be helped with current treatments.
Human trials may begin within a year, and the procedure could be ready for patient use within a few years, says Dr. J.P. Dailey, an ophthalmologist with Erie Retinal Surgery in Erie, Pa., and an assistant clinical professor at Case Western Reserve University in Cleveland.
Dailey began research on the magnetic fluid nine years ago. In the mid-1990s, he teamed up with Judy Riffle, a chemistry professor at Virginia Polytechnic Institute and State University in Blacksburg.
Riffle was to present their findings today at the national meeting of the American Chemical Society in Orlando, Fla.
Their treatment combines magnetic silicone fluid with a magnetized silicone buckle that's sewn around the outside of the eyeball. The magnetic fluid is attracted to the magnetized silicone band, and presses against the inside of the eye, pushing the retina back into place.
There are still issues to be resolved before the magnetic fluid is ready for human trials. The initial version uses cobalt to give the fluid its magnetic properties. However, cobalt may prove too toxic, so the researchers say they are experimenting with magnetite, an iron-based material believed to be less toxic.
With normal vision, the retina lies against the back wall of your eye. Light-sensitive cells in the retina absorb what you see and send those visual images along the optic nerve to your brain.
However, if a part of the retina is pulled from its normal position because of disease or injury, you suffer some loss of vision. Detached retinas that are not treated usually lead to blindness.
Your eyes are filled with a clear gel called the vitreous. As you age, the vitreous may pull away from where it's attached to the retina at the back of your eyes, Dailey explains. Most times, there is no problem as the vitreous separates from the retina.
However, sometimes the vitreous pulls hard enough to cause tears in the retina. Fluid can pass through those tears, get behind the retina and lift it off the back of the eye, Dailey says.
Current treatment for a detached retina includes injecting silicone fluid or a special gas into the eye to close any tears and push the retina back into place. However, Dailey says this approach fails in about a third of patients. That's because these materials are lighter than water and actually float in the eye, limiting their effectiveness to the upper part of the eye.
By combining magnetic fluid with a magnetic band, Dailey says the new treatment will let doctors manipulate the fluid and fix a detached retina anywhere in the eye. There are other advantages. The current silicone fluid and gases fill the vitreous cavity and can cause blurred vision, cataracts and glaucoma.
"The silicone magnetic fluid would be just a ring right up against the retina so it would not fill the inside of the eye. It would not cause cataracts or glaucoma, and wouldn't interfere with their vision," Dailey says.
One eye expert says this technique has great potential.
"It's difficult to judge at this stage, but there's good reason to think it may prove valuable," says Dr. Michael Gorin, interim chair of the ophthalmology department at the University of Pittsburgh School of Medicine.
While current methods used to repair detached retinas are highly successful, this new technique improves on those by eliminating problems such as blurred vision and cataracts, he says.
Symptoms of a detached retina include a sudden or gradual increase in the number of spots or light flashes in your eye, says the U.S. National Eye Institute. You may also notice the appearance of a curtain over your field of vision. A detached retina is a medical emergency and if you have these symptoms, you should see an eye doctor immediately, the eye institute says.
Anyone can suffer a detached retina, but people with certain conditions are at special risk. These include posterior vitreous detachment, lattice degeneration, x-linked retinoschisis, degenerative myopia and uveitis, the eye institute says. You can also suffer a detached retina as the result of an eye or head injury.
What to Do: Find out more about detached retinas at the National Eye Institute or from Prevent Blindness America.
