Manhattan resident Debora Grobman, a former federal prosecutor and white-collar criminal defense lawyer, had no idea that she was gradually going blind. But in 2006 a routine eye exam revealed that she was suffering from glaucoma, a degenerative eye disease. Her future vision is now dependent on laser surgery — she had one operation last year and may have another — and a daily regimen of five different types of eye drops.

Last week Ms. Grobman spoke at a Washington D.C. conference sponsored by the Glaucoma Foundation and the Potomac Institute for Policy Studies and appealed for more people to get tested. “Ninety percent of glaucoma-caused blindness could have been prevented through early detection and treatment,” she declared.

The conference was held in response to findings by a federally-appointed panel that found, despite the experience of Ms. Grobman and numerous others, “insufficient evidence to recommend for or against screening adults for glaucoma.” The U.S. Preventive Services Task Force, which reports to the Department of Health and Human Services, is an independent panel that makes recommendations about ways to keep people healthy. When the panel is neutral about a preventive test, such as screening for glaucoma, then managed care plans and Medicare are likely to take the test off their lists of covered benefits.

In 2006, 62 percent of people enrolled in Medicare, most of them over 65, were screened for glaucoma.

The evaluation of glaucoma testing was done by the Oregon Evidence-based Practice Center, which collaborates with the Kaiser Permanente Center for Health Research. The four authors of the study are all associated with the Kaiser Permanente Center for Health Research.

Although the Kaiser Permanente Center is supposedly independent of the managed care group of the same name — and Dr. Ned Calonge, chair of the Task Force, said that the authors received no Kaiser funding — the results of the study are favorable to the managed care industry. A recommendation by the National Commission on Quality Assurance, the independent arbiter of required procedures, that routine screening does not have to be covered, would eliminate the test, lowering costs of managed care.

One speaker, Dr. Rohit Varma, a professor of ophthalmology and preventive medicine at the Keck School of Medicine at the University of Southern California, said that the panel’s findings contradicted more recent research from the National Institutes of Health and the Research Triangle Institute. Another, Dr. Richard Parrish of the University of Miami, showed that even low to moderate visual field reduction led to increases in injuries, falls, and automotive collisions. Patients with moderate vision loss cost Medicare $345 annually in eye-related costs, and an extra $2,200 a year in other medical costs. Patients with severe vision loss costs $407 for vision treatment and an additional $3,300 in medical care; and those who are legally blind cost $237 for vision care, but an additional $4,400 for other illnesses.

These estimates, of course, omit the immense costs of quality of life, lost wages, disruption of the lifestyles of family members, modification of homes, and inability to drive a car. These are the major costs of going blind.

A routine test is relatively inexpensive compared with the cost of treating severe vision loss. But most plans may not take the long view because blindness generally occurs later in life. There is a temptation for a plan to figure, certainly with respect to younger members, that patients will no longer be on its rolls when they go blind. Most people are in any one plan for a short period of time because they change jobs — and employer-chosen health plans — frequently.

Preventive care costs far less, but the apparent cost effectiveness may depend on who gets stuck with the bills. That’s why it is contrary to the public interest to discourage early diagnosis and to leave large numbers of people uninsured until they end up in the emergency room.

Dr. Mark McClellan, former commissioner of the U.S. Food and Drug Administration and former administrator of the Centers for Medicare and Medicaid Services, stated that issues of testing and prevention are going to be of increasing concern as our population ages. The challenge of integrating preventive care into a competitive health care system is one that patients and the industry must resolve.

According to Dr. McClellan, about 95% of Medicare funds are spent on people who are sick. “We need to shift from paying for services to paying for prevention,” he recommended. Glaucoma screening is one example of such prevention — others are tests for breast and colon cancer.

A good solution, perhaps the best, is to make health care plans portable, so that people can take them with them when they switch jobs. That would give insurance companies more incentive to keep people healthy, because they will be with the company for a long time.

One could envision discounts on premiums not only for preventive care, but also for losing weight and quitting smoking, like “good driver” discounts for car insurance.

The issue of whether to screen for glaucoma is not only of importance to patients such as Ms. Grobman. It also raises a host of issues about the structure of the health care system and the role of preventive care. Allowing prevention to fall victim to cost cutting would be shortsighted indeed.

Ms. Furchtgott-Roth, dfr@hudson.org, is a senior fellow at the Hudson Institute and former chief economist at the U.S. Department of Labor.