Corneal ring can correct nearsightedness
Day surgery programs can offer a new ophthalmic refractive procedure that doesn’t involve lasers or cutting tissue from the optical zone. Implanted intracorneal ring segments manufactured by KeraVision in Fremont, CA, and marketed as Intacs, received approval by the Food and Drug Administration (FDA) in April.
At this time, other companies are researching similar products but none has received FDA approval, says Nick Taylor, spokesman for KeraVision.
About 70 million people in the United States suffer from nearsightedness. Forty-eight million people have mild enough vision problems to qualify for the implants. The ring segments are designed to correct nearsightedness for people with vision of 20/40 to 20/300.
The procedure has been in development for 20 years, with today’s version of the rings tested in humans for 10 years, says George O. Waring, MD, professor of ophthalmology at Emory University School of Medicine in Atlanta and director of refractive surgery at the Emory Vision Correction Center. Waring was one of 11 investigators performing the procedure during clinical trials.
Although the Emory Vision Correction Center was allowed to perform only 50 of the procedures during clinical trials, he points out the great consumer interest the procedure has generated. "We received 400 telephone calls from people wanting the procedure when we first advertised the trial," he says. Waring attributes the demand to a large group of people interested in surgical correction of their eyesight but reluctant to undergo laser surgery. This reluctance may be due to a fear of lasers or a fear of the permanence of laser eye surgery, he adds.
Although the procedure can be performed in an ophthalmologist’s office, Dawn Laske, practice administrator of the Northshore Eye Center in Chicago, doesn’t foresee a loss of patients for her center. "I believe Intacs will increase the number of patients for refractive correction," she says. "We offer full-service eye care including laser refractive procedures, corneal transplants, and cataract surgery, and Intacs will be one more option we can offer patients."
Laske believes that surgery centers will be used over ophthalmologists’ offices for several reasons. "A surgery center’s operating rooms are larger to give the surgeon room for equipment and staff," she says. "The operating rooms also are more sterile than a doctor’s office would be."
Implants are removable
With this new procedure, the ophthalmologist inserts two microscopic arc segments into the periphery of the cornea to flatten the cornea, correcting nearsightedness. Because the optical zone of the cornea is not affected, as in laser refractive surgery, the implants can be removed if the results are not what the patient expected. An added benefit to this procedure is that the ring segments can be removed and a different size inserted if more correction is needed, explains Waring.
Side effects can include glare as the eye heals and a need to continue using glasses for night driving.
The most obvious benefits to patients include vision improvement and no longer needing contacts or glasses, says Robert A. Wagner, ocularist and practice manager at North Corneal Services in Portland, OR, another clinical trial site. "Most patients had improved vision within one week of the surgery."
"The material used for the rings is the same material used for contact lenses, so it is safe. There is little risk of infection, and the rings can be removed if the patient isn’t satisfied," says Wagner. "It is a terrific procedure."
After 12 months and 410 patients had been treated, 97% had 20/40 vision or better and 74% had 20/20 vision or better, says Taylor.
The procedure takes about 15 minutes per eye, and the charge to the patient is typical of other refractive procedures, about $1,800 to $2,400 per eye, depending on the day surgery program’s market, Taylor adds. This cost typically is paid out-of-pocket by the patient.
While most insurance companies don’t pay for refractive surgery because it is considered a surgical replacement of glasses or contacts that is not necessary, Wagner has found some payers cover some of the costs.
This is an ideal procedure for day surgery programs for several reasons, says Waring. Topical anesthesia is administered by eyedrops, so recovery room time and recovery room nurses are not needed. There is a start-up cost of about $50,000 to purchase the specialized surgical equipment manufactured by KeraVision for insertion of the corneal rings, and the disposable supplies cost about $65 to $75 per case, he adds.
KeraVision is setting up training courses for physicians who want to perform the implant insertion, but there will be about two months of training and monitoring before a surgeon can perform the procedure alone.
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