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STATEMENT OF DR. CARL KUPFER

Mr. Chairman, it is always a pleasure to testify before this Committee and share some of the many research advances that each year help us better understand the marvelous complexity of the human eye. Many have led to great improvements in our ability to prevent, diagnose, and treat blinding eye and visual disorders. This year, however, I would like to begin my comments by bringing to your attention a disturbing new finding. Based on projections

from a recent NEI-supported survey, as many as one million Americans may now be blind.

While there are many causes for blindness, one of the most significant is aging. Because older Americans now represent a rapidly growing segment of our society, age-related eye diseases--such as cataracts, glaucoma, diabetic retinopathy, and macular degeneration--have correspondingly increased in importance as causes of blindness.

related eye

In fact, it may be that blinding age

diseases are more prevalent today simply because more Americans

now live long enough to develop them.

Without increased understanding of the aging eye, I believe further increases in blindness will occur. To help bring about this understanding, the Institute now supports a number of relevant basic and clinical investigations. For example, we have recently begun the Age-Related Eye Diseases Study (AREDS), a multi-center research project that will follow the development and progression of cataracts and age-related macular degeneration in a group of older Americans. Since the AREDS is the first large-scale attempt to track the natural history of these diseases, the NEI hopes that the study will help provide the scientific basis for future prevention strategies. Although age-related eye diseases represent one of the NEI's most important areas of current and future investigation, the Institute also faces several other significant research challenges. I have mentioned in previous years that nearly 40 percent of all sensory input into the brain originates from the eye. If scientists can begin to understand better the remarkable complexities of the visual system, this knowledge can be applied to help unlock age-old mysteries of not only human behavior, learning and memory,

but

also neurological disease. For this reason, NEI programs are an integral part of the "Decade of the Brain" initiative..

For example, it is well established that brain tissue loses its ability to divide and grow immediately after birth. Because researchers have been

unable to learn the biological secret that would allow them to regenerate brain cells, serious neurological injury can have devastating consequences on basic human skills, such as vision, speech, memory, and movement. Recently, however, NEI-supported vision researchers isolated two growth factors within the retina, which is considered to be a part of the brain. One of these natural compounds, basic fibroblast growth factor (bFGF), actually prevented animal retinal cells from degenerating in preliminary studies, and thus prevented severe visual loss and blindness. It is reasonable to assume that the continued study of retinal growth factors could provide the underpinning for similar work on other brain cells.

Studies aimed at transplanting retinal cells also show considerable

promise for brain research.

Although the successful transplantation of brain

cells would provide enormous therapeutic benefits to people affected by brain disorders or trauma, scientists have been unable to accomplish this in laboratory animals. However, an NEI-supported team of vision researchers report the successful transplantation of retinal cells in animals. Again, it is possible that the future refinement of such work in retinal cells may provide many of the keys that will one day allow us to apply this to the

brain.

On another research front, I am pleased to report that vision researchers have begun to identify the mechanisms underlying corneal scarring. When the cornea -- the eye's transparent, outermost tissue--is severely damaged, it becomes irreversibly clouded, resulting in varying degrees of vision loss. Because corneal diseases account for nearly 25,000 new cases of blindness in this country each year, a greater understanding of this problem is essential to vision research.

NEI-supported scientists have recently identified and cloned the genes that cause corneal scarring. With this finding, scientists can now work to develop drugs that block the activation of these genes, reduce corneal clouding, and thus minimize vision loss due to corneal injury. Moreover, since the cornea has historically played a central role in the study of general wound healing, scientists may also be able to study these genes to

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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.

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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

disease.

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

manner.

Before concluding, I would like to reiterate the great social benefit of
Indeed, since most people rely on vision for virtually all

vision research.

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

is $272,260,000.

I will be glad to answer any questions that the Committee

might have.

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
School, 1952 Certified. Amer. Bd. of Ophthalmology, 1958.

Professional History: Internship and Assistant Residency, Wilmer Eye Inst.,
Johns Hopkins Hospital, 1952-54. Lab. Assistant, Biostatistics, Johns Hopkins
School of Medicine, 1953-58. Research Fellow in Ophthalmology, Harvard
Medical School, 1958-60. Instructor in Ophthalmology, Harvard Medical School,
1960-62. Asst. Prof. of Ophthalmology, Harvard Medical School, 1962-66.
Prof. and Chairman in Ophthalmology, Univ. of Wash. School of Medicine;
Research Affiliate, Univ. of Wash. Primate Ctr., 1966-70.

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, Education and Welfare (DHEW), 1972; The Superior Service Award, DHEW, 1974; Presidential Rank Award of Meritorious Exec., 1983; Migel Medal, Amer. Foundation for the Blind, 1976; Public Service Award in Ophthalmology, Amer. Acad. of Ophthalmology and Otolaryngology, 1977; Special Award of Honor, The Assoc. for Research in Vision and Ophthalmology, 1983; David Rumbough Memorial Scientific Award, The Juvenile Diabetes Found., 1983; The Lighthouse Pisart Vision Award, 1984; Cavera Medal of Univ. of Rome, 1985; The Mildred Weisenfeld Award for Excellence in Ophthalmology, 1987. President's award for distinguished excellence in the Senior Executive Service, 1990.

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