A Patient-Centered Research Career
Interview with Frederick L. Ferris III, M.D.
By Susan E. Johnson
NEI Science Writing Intern
Frederick L. Ferris III, M.D.
National Eye Institute
Frederick L. Ferris III, M.D., has spent his 37-year professional career conducting clinical studies at the National Eye Institute (NEI). He arrived in 1973 for a National Institutes of Health fellowship as a commissioned officer in the U.S. Public Health Service. In each of his roles--from novice epidemiologist to NEI clinical director--Ferris has been a leader in most of the NEI's long-term medical studies involving thousands of participants at the NEI clinic and clinics around the country.
In a recent interview, Ferris discusses the progress he's witnessed in vision science and his hopes for future research that will improve the sight of people around the world.
You were on the team that carried out the first major clinical trial in ophthalmology. What were you studying?
That was the Diabetic Retinopathy Study, which started in the early 1970s. It involved the use of laser photocoagulation treatment of damaged blood vessels caused by diabetic retinopathy. In this eye condition, diabetes causes excessive growth and leakage of blood vessels in the retina, the light-sensitive tissue in the back of the eye. Because this was the first major clinical study in the field of ophthalmology, we all faced a steep learning curve.
What was one major obstacle you encountered?
It is interesting that in this first major clinical trial, the definition of blindness turned out to be a major obstacle. We evaluate vision by asking the patient to read the letters on an eye chart out loud. We didn't even think about the fact that patients might learn the letters after several visits. So when they came in for a follow-up exam, they might have been able to recite the letters even if they couldn't read them. This was especially true for the level of "legal blindness," which is a reading of 20/200. There was only one letter on the chart that people could see for this level of vision--the large E. That's a letter that people could easily remember. When we realized this, we had to develop new charts that most people could never possibly memorize--different charts for the right eye, for the left eye, and for assessing which type of glasses they needed. It was a very interesting time, and we were very fortunate that the study was a great success.
What have health care professionals learned about diabetic retinopathy from clinical trials?
In our clinical trials of treatments for diabetic retinopathy, we demonstrated the effectiveness of laser treatment combined with surgery on the vitreous gel inside the eye, when necessary. This can reduce the risk of blindness by more than 90 percent in people who have abnormal new blood vessels in the eye that develop in late stages of diabetic retinopathy. With this treatment, less than 1 percent of people in this high-risk group become so visually impaired that they can't get around. This is an amazing finding because before this, more than half of people with this degree of diabetic retinopathy went blind.
What other eye conditions have you studied through clinical trials?
Participants in clinical trials often undergo painless imaging tests of their eyes, including optical coherence tomography, shown here.
I spent my first 20 years at the NEI looking at diabetic retinopathy. During the past decade, more of my research has involved age-related eye diseases, such as age-related macular degeneration (AMD). AMD is a disease that gradually destroys the macula, the part of the retina that provides sharp, central vision. It's a leading cause of blindness in this country. We've been trying to better understand risk factors for the development of this disease, such as diet, which will hopefully lead to new interventions that will prevent AMD. In a recent study, we were fortunate to find out that dietary supplements consisting of high doses of zinc and beta-carotene as well as vitamins C and E could reduce the risk of advanced AMD. Now, we're building on that first trial to see if additional supplements can further reduce the risk.
What are some of the long-term goals for clinical eye research?
What I'm focused on personally is reducing the risk of AMD. But, overall, we have great opportunities now that we have access to so much information about the human genome. Genetic information will help us learn why some people develop certain eye diseases while others don't. Researchers and clinicians will discover critical information, using epidemiologic approaches to combine genetic knowledge with environmental risk factors and personal characteristics. This understanding will inevitably allow us to tailor treatments for patients who have different genetic traits.
You've been at the NEI for more than 30 years. What has made you so dedicated to your work?
It's the excitement of doing new clinical studies. Compared to my grandparents' expectations of life, we look forward to living much longer and healthier--and rightly so. But we don't want to look forward to living into our 80s and 90s if we're going to be blind. Our clinical trials at the NEI have already made a huge difference for diabetic retinopathy, and we're on the brink of making the same breakthrough for AMD. So, I guess I could retire, but vision research is now more exciting than ever.