Science & Technology
A SURGEON WHOSE HANDS NEVER SHAKE
The automatic drill attached to a mechanical arm bores a precise channel down an uneven cylinder. It's standard industrial technology, commonplace from toy factories in Taiwan to machine shops in Toledo. But on this day in Sacramento, this robot is doing something new: Surrounded by doctors and technicians, it's burrowing down a femur, the thighbone of a human being.
Robots are marching from factories into operating rooms, and why not? They follow orders to a tee. They don't cough or sneeze, and they're unperturbed by the sight of blood. Most important, they're masters of exactitude. "A human can't make a precise adjustment of 2.8 mm," says Russell Taylor, manager of robotics and augmentation research at IBM. "A robot can."
MODELS. Machines such as the thigh-reaming Robodoc, for which the Food & Drug Administration is about to okay a final round of tests, will provide more than a steady grip on a scalpel. In labs from Palo Alto to Paris, engineers and surgeons are linking robots to computer workstations and imaging equipment. Using these technologies, many of them hand-me-downs from the military, researchers can see inside the body and create computer models of it. This lets a surgeon, working with a computer mouse, bore holes for hip replacements, zap a brain tumor more accurately with radiation, or operate on fetuses. Visionaries see the day when doctors sitting at a computer will do robotic surgery half a world away.
That's the kind of talk that brings startups out of the woodwork. When the Pentagon's Advanced Research Projects Agency offered grants earlier this year under the Clinton Administration's Technology Reinvestment Program, ARPA's new health-care technologies division was flooded with proposals for surgical robots. General Electric Co. and IBM are in the chase, too. And many surgeons, warming to the idea of robots as assistants, are jostling to test prototypes.
Before robots blaze this dazzling trail, doctors will have to calm patients. "We have to get people away from the notion that this is an R2D2 machine that goes nuts," says Bela Musits, president of Integrated Surgical Systems Inc. (ISS), the Sacramento maker of Robodoc. Just as important, Western societies have to decide how many such machines they can afford. "We'll have to perform real cost-benefit analyses," says Anthony M. DiGioia, director of orthopedic research at Shadyside Hospital in Pittsburgh, which has bought a Robodoc.
Meantime, it makes sense that robots start at the hip. That surgery is among the most primitive, with the doctor sawing and hammering at a patient's leg and digging a tunnel down the femur to anchor the implant. Surgeons use cement, so the fit isn't crucial. But the cement eventually breaks down, forcing many patients to get replacements in 10 or 15 years. If the operation can be done without cement, the bone will graft itself onto the implant, creating a stronger bond. That approach, though, requires pinpoint precision.
EARLY SUCCESS. This problem vexed Dr. William Bargar, a Sacramento orthopedist, and a colleague, the late Hap Paul, an orthopedic veterinarian. Bargar and Paul knew that automatic milling machines could cut precision holes. But, says Bargar, "robots are basically stupid. We were talking about a complex task." The challenge was to customize a hole for each patient. Luckily for Bargar, his father, an IBM retiree, helped get the computer giant behind ISS.
Last November, the startup unveiled Robodoc, and Bargar used it on 10 patients with apparent success: It carved tight fits, reducing the chance that the implants would ever jostle loose. Once the FDA gives its nod, doctors in five hospitals around the country will start the last stage of tests on Robodoc. Musits hopes to sell "several hundred" of the $500,000 systems by 1996 to a large world market: Some 750,000 hip replacements are done each year, one-third in the U.S.
In theory, at least, hospitals will bite in the hope that Robodoc will bring them more patients. Hip replacements now cost an average $7,432 in the U.S., says Gail Latimer, an administrator at Shadyside Hospital, and most hospitals lose money on them. Even if Robodoc is a success, hospitals won't be able to charge a premium because health insurers won't pay the difference. Still, a Robodoc might bolster a hospital's reputation as a leader in bone surgery--and attract patients for other orthopedic procedures that do make money.
Of course, surgeons have used computers and imaging equipment for years. With MRI, CT scans, and ultrasound, they've looked inside the body at brain tumors, sprained knees, and embryos. But to date, they've used these just to see, not act--which is why Robodoc is such a giant step. First, technicians place three pins in a patient's leg to give the robot bearings for doing its work. Then they take CT scans of the patient's hips and deliver them to the computer workstation, which develops three-dimensional models of the bone and body structure. Using a mouse, the surgeon selects an implant of the proper size and shape and maps out the surgery. With its work limited to the femur, Robodoc works for about 25 minutes of each 150-minute operation. Looking like a wand with a tiny whirring propeller at its end, the machine slowly tunnels into the bone as the surgeon monitors its progress--with one finger on the pause button.
Already, doctors and scientists at Carnegie Mellon University are developing robots that can do the other half of the surgery, preparing the hip for the artificial socket. If these tests are a success, predicts DiGioia, robots will soon handle any kind of surgery where bone must be whittled or shaped, including on knees, ankles, and shoulders. Bargar also sees a place for robots in back surgery, where a precision machine could work close to the spinal cord without harming it.
Not every robot will work on bones. In Santa Clara, Calif., a group of engineers and physicists, many of them refugees from defense industries, are building robots for use in battling brain tumors and lesions. Currently, using a $4.5 million machine called the gamma knife, doctors have to radiate much of the brain to battle a tumor. By contrast, the new machine, the Accuray 1000, uses a CT scan to develop a three-dimensional model of the brain. Once it knows where the tumor is, the machine can hit it with just the right doses of radiation from hundreds of angles. Dr. David S. Zorub at Shadyside in Pittsburgh calls the $2 million Accuray "the ultimate precision tool." Zorub, one of several surgeons who will test Accuray once the FDA approves, next sees robot-delivered radiation for pancreas, breast, prostate, and lung cancers.
EXPLORING. Still other ideas are coming to life in labs. At Northwestern University, researchers are developing tiny robots that will battle blindness by injecting clot-dissolving drugs into blood vessels in the eye. A surgeon would control these devices remotely while looking through a microscope. Scientists in Britain, meanwhile, are working on camera-wielding micromachines that can be inserted through the navel to help explore a body's innards. Much like fighter pilots, who steer and aim by moving their heads, helmet-wearing surgeons could turn their heads left, right, up, or down to see a patient's insides.
Once the technology advances that far, a doctor in San Francisco could in theory don a helmet and "walk through" a body in Germany or Saudi Arabia. In the near term, this would allow far-away specialists to consult with colleagues on difficult cases. Eventually, scientists say, doctors could perform robotic surgery this way. The Pentagon is sponsoring research in the area to develop better battlefield surgery. Progress hinges on continued advances in three-dimensional imaging and on learning how to manage time: Even with images and commands traveling at the speed of light, there can be disorienting one-second lapses between a doctor and a faraway robot. Still, that problem hasn't stopped boosters from giving the remote procedure a name: Nintendo surgery.
Researchers who are piecing together these new systems must keep one eye on the national debate over health care. For while the horizons for robotic surgery are nearly limitless, America's ability to pay for them isn't. This may push research toward machines that can cut medical costs. The challenge, after all, is to satisfy a public that not only demands miracles, but cost-effective ones.Stephen Baker in Pittsburgh