Thursday, April 3, 2008

Older Corneas Are Suitable for Transplantation, Nationwide Study Shows

Corneal transplants using tissue from older donors have similar rates of survival to those using tissue from younger donors, reports a nationwide study recently concluded at Emory Eye Center and 79 other sites.

The five-year transplant success rate for recipients was the same - 86 percent - for transplants performed across the nation with corneas from donors ages 12 to 65 years and from donors ages 66 to 75.

Because of this new finding, the donor age pool, currently limited to donors 65 and younger, should be expanded to include donors up to 75 years of age. These are the conclusions of a study funded by the National Eye Institute (NEI) of the National Institutes of Health, and published in the April issue of the medical journal Ophthalmology.

“This pivotal study indicates that corneas from older individuals are just as successful when used for transplants as those from younger donors,” says R. Doyle Stulting, MD, PhD, director, Section of Cornea, External Disease and Refractive Surgery at Emory Eye Center. “These study results will expand the donor cornea pool and make the scheduling of transplant procedures easier for both surgeons and patients.”

The availability of donor corneas has been adequate for the past 10 years in the United States, where more than 33,000 corneal transplants are performed each year.

However, recent changes in Food and Drug Administration (FDA) regulations will likely cause a decrease in the supply of donated corneas, says Stulting. These new regulations require additional screening and testing of potential donors for contagious diseases, registration of eye banks, more detailed records and labels and stricter quarantine procedures. In addition, many eye banks previously set the age limit for donors at 65 years or younger because some surgeons have been reluctant to use older corneas. The findings from the new study could lessen these restrictive policies.

Emory Eye Center is one of 80 sites that participated in the Cornea Donor Study (CDS) that helped bring together more than 1,101 participants and 105 surgeons from across the United States. Participants from Emory were between ages 40 and 80 and were chosen for the study if they were in need of a corneal transplant for a corneal disease that put them at moderate risk for clouding of the transplanted cornea.

After the transplant surgery, the participants were followed for five years. The transplant was considered a failure if a repeat corneal transplant was required or if the cornea was cloudy for at least three months. Donor corneas were provided by 43 participating eye banks. All donor corneas met Eye Bank Association of America standards for human corneal transplantation and were consistent with eye banks’ tissue ratings of good to excellent quality.

“The pressure on eye banks to provide corneas is increasing,” says Paul A. Sieving, MD, PhD, director of NEI. “The results of this study will expand the available donor pool and should persuade surgeons to use corneas from older donors. These changes will greatly benefit the growing number of individuals who need corneal transplants.”

Overall, the demand for organs and tissue is greater than the supply available for transplantation. In the United States, the U.S. Department of Health and Human Services Health Resources and Services Administration oversees the federal government’s Organ Donor Program. This program is designed to increase awareness of the critical need for organ and tissue donors. For more information, go to http://www.organdonor.gov/.

No comments: