Surgeons work on technique to treat eye disease
April 26th, 2007
Before one can run, he must walk. Before surgeons can use a new technique, they must know that it works.
University of Louisville ophthalmologists Henry Kaplan and Tongalp Tezel have taken a first step to develop a surgical technique that effectively removes and replaces diseased eye tissue in an effort to find an effective treatment for age-related macular degeneration (AMD).
AMD blurs the sharp, central vision needed for “straight-ahead” activities such as reading, sewing and driving. The disease affects more than 1.75 million people in the United States, where it is the leading cause of blindness. With the rapid aging of the U.S. population, it will affect almost 3 million people by 2020.
“Current treatments can only slow down the progress of AMD or at best increase the vision for a short period of time. They cannot heal the damaged tissue,” Tezel said. “Our development of this technique is the first step in our efforts to treat AMD through tissue reconstruction and regenerative medicine, which is significantly different from current techniques that simply remove diseased tissue.”
Kaplan and Tezel developed the surgical technique and with collaborators designed and built specific instruments required for the procedure. Their study, was the nation’s first controlled prospective clinical trial of retinal transplantation on multiple patients with AMD.
The clinical trial included 12 patients over the age of 60. The surgeons removed abnormal blood vessels and scar tissue from their eyes and replaced the tissue with that from donors. The patients received drugs, similar to those given to kidney transplant patients, to suppress the immune system and avoid rejection of the donor tissue.
While patients in this trial did not see significant visual improvement in the initial year after surgery, the study proved that the surgery is technically feasible and that widely-used immune-suppressing drugs will keep foreign eye tissue from being rejected.
Kaplan and Tezel published their results this month in the American Journal of Ophthalmology. According to an accompanying editorial, the study is a milestone in proving that cell-based therapies for AMD are feasible.
“We have since taken the observations from this study to help us direct our tissue engineering efforts — called ‘;maculoplasty’ — that offer hope for reconstruction of the tissues involved in macular degeneration and other diseases,” Kaplan said.