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learn more about how various parts of the body respond to injury, and thereby develop better ways of improving wound healing.
Since the genesis of vision research, scientists have wondered why the eyeball sometimes grows excessively long during childhood, causing the common problem of myopia, or nearsightedness. I am happy to report this year that we may at last have a compelling new clue about what causes this condition that affects roughly one-third of the population. NEI-supported investigators have recently produced exciting new evidence suggesting that local retinal neurotransmitters--molecules that allow communication between cells--may actually play a role in the development of nearsightedness. The researchers have identified the neurotransmitter dopamine as a possible factor in the control of the developing eye. Indeed, dopamine-enhancing drugs were shown in animal studies to partially protect the eye from myopic elongation. Although this work is still in its early stages, these findings offer science an intriguing new direction to follow in attempting to answer the age-old question about the cause of myopia.
The National Eye Institute also continues to support clinical research on new methods for the diagnosis and treatment of eye diseases. I would like to tell you about some of the more important of these clinical trial results that were reported during the last year.
The first involves the ongoing Prism Adaptation Study (PAS). About 4 percent of all Americans have some form of cross-eye, the inability to direct both eyes to the same object. For most individuals, surgery is the most effective way to correct this disabling problem. Unfortunately, surgery is not uniformly effective, since nearly half the patients who undergo surgery need more than one operation to correctly realign their eyes.
But, in its preliminary findings, the PAS reported that patients who wear eyeglasses with special prisms for one month prior to their operation are more likely to undergo successful surgery. If future study results bolster the early finding, this marvelously simple strategy will yield considerable savings in expense, trauma, and surgical risk for Americans with cross-eye. The NEI-supported Glaucoma Laser Trial (GLT) also reported a very hopeful early finding this past year. Traditionally, drugs have been used to treat glaucoma, a sight-threatening increase in pressure inside the eye. However,
the GLT found after two years of study that argon laser therapy appears to be a safe and effective alternative to eye drops for newly diagnosed open-angle glaucoma patients. Although these early findings are promising, GLT clinicians will follow patients for an additional three years to better determine the treatment's long-term safety and efficacy. This extended follow-up period is necessary because glaucoma is a chronic disease with a variable rate of progression.
As NEI support of the GLT suggests, glaucoma continues to be an important area of NEI research interest. Two NEI-funded epidemiology studies, the Barbados Eye Study and the Baltimore Eye Survey are providing reliable new data on the prevalence of this potentially blinding disease. For example, Baltimore Eye Survey findings show that primary open-angle glaucoma is sixtimes more prevalent in Blacks over age 40 than in Whites. Because glaucoma is an age-related eye disease, these findings emphasize how important it is that middle-aged Black people need to have a comprehensive, dilated eye examination for glaucoma to reduce their risk of visual loss from this
One means that the NEI will utilize to encourage this practice is the National Eye Health Education Program (NEHEP), a public education effort mandated by the Congress. After close consultation and interaction with numerous voluntary and professional organizations, the NEHEP will this year launch a multi-media campaign targeted to Blacks over age 40 and all people over age 60 emphasizing the necessity of periodic glaucoma testing. Another NEHEP program will be targeted to the nation's more than 14 million people with diabetes who are at risk of developing diabetic eye disease, a leading cause of adult blindness.
The NEI will also continue its efforts to help treat the devastating eye complications of AIDS. Specifically, cytomegalovirus (CMV) retinitis is the most common cause of severe vision loss among AIDS patients, affecting an estimated 25 percent of all victims of this disease. Unfortunately, this problem can be difficult to treat because both current drugs of choice, ganciclovir and foscarnet, can have toxic side effects, and at best can only control, not cure, the disease.
To learn more about the comparative safety and efficacy of these drugs in
AIDS patients, the NEI has begun the CMV Retinitis Trial. This clinical trial will evaluate the toxicity of ganciclovir and foscarnet, as well as monitor these drugs' effects on patient health and survival. The CMV Retinitis Trial is the first study conducted under a collaborative clinical research project called Studies of the Ocular Complications of AIDS (SOCA). SOCA has been designed so that as promising new therapies for AIDS-related eye diseases become available, they can be rapidly tested in a scientifically rigorous
Before concluding, I would like to reiterate the great social benefit of Indeed, since most people rely on vision for virtually all aspects of their daily lives, Institute-supported studies will continue to have a great impact in helping all Americans, young and old, maintain a high quality of life. As always, I look forward to keeping this Committee informed of the great progress that future vision research will certainly bring to the American public.
Mr. Chairman, the FY 1992 budget request for the National Eye Institute
I will be glad to answer any questions that the Committee
BIOGRAPHICAL SKETCH OF DR. CARL KUPFER
Director, National Eye Institute
February 9, 1928. New York, New York.
Education: A.B., Yale Univ., 1945-48. M.D., The Johns Hopkins Medical
Professional History: Internship and Assistant Residency, Wilmer Eye Inst.,
Professional Organizations: Amer. Physiological Society; Assoc. for Research in Vision and Ophthalmology; American Academy of Ophthalmology; American Ophthalmological Society; Pan American Ophthalmological Society; Johns Hopkins Univ. Soc. of Scholars; Member, Inst. of Medicine, Nat'l Academy of Sciences.
Honors and Awards: The Secretary's Special Citation, Dept. of Health,
Invited Lecturer: Dunphy Lecture, 1977; Lorand V. Johnson Lecture, 1980; C.
Other Scientific Activities: Editorial Bd, Investigative Ophthalmology,
International Appointments: Mbr, Brd. of Trustees, Helen Keller Internat'l
Senator HARKIN. I just learned something new that I will have to remember. The back part of the eye is part of the brain.
Dr. KUPFER. Yes, sir; it is.
Senator HARKIN. I'll have to think more about that.
Tell me this. Why is this? When I was 30 years old and a fighter pilot in the Navy, I had 20/15 vision. I had great eyesight. And about age 43, 44, somewhere in there, all of a sudden there were things I couldn't read too well any longer. So, I had to get a pair of glasses, and they gave me these reading glasses. Then it got worse and worse. I am now 51. It seems like I went along and it took one drop and it sort of leveled off. Then it took another drop. Now it has leveled off, and I have to wear these now. Why is that?
I can understand if you are born with an unhealthy eye or something, but when you have really healthy eyes and you have good eyesight, what happens? Why does it always happen around ageas I am told, around 45 to 50 years of age?
Dr. KUPFER. That is correct. Your information is quite correct. The ability for us to look from a distance to near depends on changing the shape of the lens inside our eye. This ability to change the shape begins to decrease about the age of 40. So, that is why we need help from reading glasses or bifocal contact lenses, such as I and others wear to enable us to see what is close.
Now research is being done on this condition, as you might imagine. It is very distressing, especially for those of us who have never worn glasses. Perhaps in the next 5 or 10 years we will have ways to correct this problem.
Senator HARKIN. I can't wait. [Laughter.]
How much more money do you need in your budget? [Laughter.]
Senator HARKIN. I wanted to ask one other question about glaucoma. Two typical treatments for glaucoma are medications, which reduce the pressure, and surgery to accomplish the same purpose. What can you tell us about the relative effect of these two approaches and quality of life considerations? Which is the better approach? Or is there one that is better than the other, or does it depend upon the situation?
Dr. KUPFER. That is an excellent question. The situation with glaucoma is that it is completely asymptomatic. This is the openangle glaucoma which is the most common. Therefore, the individual can lose visual function without really being aware of any signs or symptoms until very late. When the diagnosis is made, we ask the patient to take drops. These drops themselves sometimes have adverse effects, plus the fact that it is very difficult to remember to take drops once, twice, or three times a day.
On the other hand, to lower pressure, another possibility would be to perform a surgical intervention which creates a new path for the fluid to leave the eye.
We do not know which is the better intervention. As a matter of fact, we are considering supporting a clinical trial which will randomly assign individuals who are newly diagnosed as having glaucoma to either medical treatment or surgical treatment with one of the major outcomes being which offers a better quality of life. So, in a number of years-hopefully not more than 3 or 4-we will begin to have information on this very question.
I might say that in the United Kingdom, surgery is now used as the primary intervention, whereas in the United States, we still prefer medical treatment as the primary intervention. This clinical trial will give us a very definitive answer.
QUESTIONS SUBMITTED BY THE SUBCOMMITTEE
Senator HARKIN. Good. I look forward to that.
Dr. Kupfer, thank you. I have some additional questions which we will submit to you in writing.
[The following questions were not asked at the hearing, but were submitted to the Department for response subsequent to the hearing:]