Remote Control

Trade your scalpel for a joystick — and gain a surgical team member with an incredible set of hands

By Krista Conger
Illustration by Christoph Niemann
Photographs by Leslie Williamson

SIDEBAR: Robots: The next generation turning science fiction into fact

 

Surgeons work with their new team member, a surgical robot, swathed in protective plastic.

Two-month-old Daniel Pham’s belly, protruding from sterile blue surgical drapes and bristling with specialized surgical instruments, was the only visible part of his body on the morning of Jan. 9, 2004. His operation was at a critical point when pediatric surgeon Craig Albanese, MD, turned his back and walked away from the table. He didn’t return.

Daniel’s fate was left in the hands of a 7-foot-tall, three-armed surgical robot called da Vinci®. Hovering over the table, the robot’s spidery arms clutched his small body like a helpless insect. As the surgery proceeded, the arms moved quickly and jerkily, swooping around Daniel as if wrapping him in an invisible web.

Although it might sound alarming, the robot, which arrived at Stanford last October, was on a tight leash: Every move was controlled by Albanese from a workstation positioned against a wall in the operating room, with the robot’s unnervingly jerky moves translated into tiny, precise and very, very steady maneuvers inside Daniel’s body.

“We’re changing the culture of surgery,” says Albanese, chief of pediatric surgery. “Usually we have our hands in there, feeling and doing. Now we’re taking several steps away to sit at a remote console. It’s kind of an out-of-body experience.”

Albanese isn’t alone. With the advent of robotically assisted surgery, physicians are swapping the immediacy of warm flesh and blood for the smooth plastic of computer joysticks. More than 200 da Vinci robots have been conscripted into operating rooms worldwide, and the scope of their influence seems poised to grow — a bittersweet bargain driven by the promise of better patient care.

“We’re always looking for solutions to unsolved problems, whether in the operating room or the laboratory,” says Lucile Packard Children’s Hospital surgeon-in-chief Thomas Krummel, MD, who also participated in Daniel’s surgery. “Although traditional open surgery is very intuitive — we can pick something up, see it in three dimensions and move it freely in space — there’s nothing therapeutic about the accompanying large incisions,” says Krummel, chair of Stanford’s surgery department. “Not only must they be repaired, they can cause the patient discomfort and become infected.”

Laparoscopic, or minimal access, surgery has gained wide acceptance in the recent past as an alternative to many open surgeries. It relies on small incisions and specialized instruments to reduce patient discomfort and speed healing.

Laparoscopic surgery is not perfect, however. Such tiny entry points cause unavoidable technical problems: Surgery must be viewed on a monitor with the help of a small internal camera and the laparoscopic instruments can’t provide the tactile feedback and range of motion of the human hand and wrist.

“Laparoscopic techniques allow us to perform maximal surgery with minimal access,” says Krummel. “But this advance comes at a price: We’ve lost 3-D vision, and we’ve lost a wrist. Most laparoscopic tools are like long chopsticks. Imagine trying to eat with your arm in a cast and one eye closed; it feels a little clumsy.”

Laparoscopy also requires the surgeon to adapt to an alternate physical reality: to move the tip of an instrument to the left, the end outside the body must be moved to the right. “You lose the correspondence between what you do and what you see,” says J. Kenneth Salisbury, PhD, professor of computer science and of surgery.

The da Vinci Surgical System, manufactured by Intuitive Surgical Inc. based in Sunnyvale, Calif., is an attempt by physicians and researchers from around the country — including Salisbury and Krummel — to have their cake and eat it too. They’re trying to deliver the benefits of minimal access to the patient while simultaneously returning to the surgeon the look and feel of open surgery. It’s a tall order, but they’re making progress. Future versions may come even closer [see sidebar, next page].

One trade-off still exists, however: the surgeons move closer to the past by moving away from their patient. As was obvious with Daniel’s surgery, da Vinci effectively shifts the center of the action from the operating table to a console stationed about 10 feet away from the patient. The console, featuring an overgrown version of a child’s View-Master with hand-operated joysticks and foot pedals and a comfortable seat, gives the surgeon a three-dimensional, magnified view of the ongoing surgery.

The da Vinci gives the surgeon total control of two instruments and a camera; hand and foot movements are translated into the steady, precise and unrestricted movement of the robot’s arms, which hold specialized surgical instruments with wrists that approach a human’s in mobility and dexterity. Other members of the team view the action on a monitor perched next to the operating table.

 

Craig Albanese, pediatric surgeon, finds a surgical robot allows him to work with more precision and less fatigue and strain than possible with traditional surgery.

“It’s incredibly comfortable,” says Albanese. “Surgery can be tiresome and ergonomically unpleasant. With the robot, I can place my head in a comfortable viewing box and rest my arms on a cushioned armrest. Then I go about moving my hands and arms just like I would in a traditional surgery. The console is so quick and easy to get used to that the learning curve is minimal.”

Although it is physically easy for an experienced surgeon to learn to use the robot, the psychological learning curve may be a bit more bumpy. Salisbury has observed one surgeon who, after performing most of an operation with da Vinci’s help, stopped and temporarily wheeled the robot away from the patient to perform a critical cut by hand.

“When I asked him why, he said ‘I just wanted to make sure it was right,’ ” says Salisbury, “and yet, there was still an important role for the robot to play in his operating room. That’s the kind of challenge we’re facing as we design the next generation of machines: How do we get that feeling back?”

The question is a difficult one. It’s obvious that, in many ways, working at the console can seem more real than virtual for some surgeons. “I’ve seen surgeons using the robot who drop the needle in the patient and move their head from the viewing box to look for it near their own hands,” says Salisbury, who helped develop the flexible wrists used by the da Vinci’s instruments.

A microphone connected to a speaker near the operating table amplifies the surgeon’s voice for the rest of the surgical team, instructing them when to swap instruments, commenting on the procedure, or conferring with the surgeon at the patient’s side.

 

A sewing demo by two of the robot's three arms

“The robot filters out any hand tremor and scales motion,” says Albanese. “I can move my hands 5 centimeters, and the instrument moves only 1. This allows more sweeping motions and increases the comfort and precision of the surgery. The range of motion is also much greater than with laparoscopic instruments.”

One drawback to the robotic system, though, is the absence of any sense of touch or force feedback. It’s no longer possible for a surgeon to feel the texture or firmness of an organ or to use resistance to judge when a suture is perfectly tied.

“We now rely on visual cues to tell us if we’re grasping too firmly or pulling too hard on a knot,” says Albanese, “so the robot is still not perfect.”

Surgery also requires exquisite teamwork, and incorporating da Vinci into the mix is like inviting a bossy elephant into already tight quarters. Every incision must be carefully planned to allow a full range of motion for each robotic arm, which together monopolize a hemisphere of space above the patient. Human members of the surgical team are relegated to dodging the moving arms while using additional incisions, or ports, to provide suction or to retract organs or tissue.

“I don’t work in a vacuum,” says Albanese. “The robot sits idle and collects dust unless I have a scrub nurse who’s fabulous and an anesthesiologist who has bought into the idea and doesn’t mind the change in culture.” It’s also necessary for an experienced surgeon to remain at the operating table to monitor the patient’s condition and swap the instruments attached to the robot’s arms.

“The surgeon sitting at the console has the easy part,” says Albanese. “The one standing at the bedside needs to be very experienced in aligning the robot’s arms, which can make or break a case.”

“We don’t reach out and ask for a robot like we might ask for a needle driver,” agrees Krummel. “To get such a large machine around a kid is no mean feat. As in laparoscopic surgery, there is a lot of geometry to be worked out before the operation begins; parallel instruments can’t work together as effectively as those with a greater angle between them. All this requires an experienced crew to make it work.”

The Stanford team has two members who count themselves among the robot’s closest companions. They’re general surgery residents Russell Woo, MD, and David Le, MD, who were research fellows at Intuitive. “They have more experience with the robot than virtually anyone in the world,” says Albanese. During the surgeries, Woo troubleshoots at the console and Le assists at the bedside.

Scrub nurse Rosette Reyes, RN, has participated in all three of da Vinci’s pediatric surgeries.

“It was a little intimidating at first,” says Reyes, “but now it’s becoming just another way to do a procedure.

“It’s a very good step in the right direction and it helps better the care of the patient,” adds Reyes. “Children have so many years ahead of them that we’re really helping them to begin their lives, in a way.” It makes sense to use the best tools available, despite any minor annoyances, she says.

Daniel, who suffered from a potentially fatal congenital condition called biliary atresia, is doing well. His surgery marked the first time that the robot had been used to correct this problem. The da Vinci has already lent an arm or three in about a dozen surgeries since its arrival.

“The wonderful thing is that by restoring three-dimensional vision and a versatile wrist, the robot gives you the benefits of laparoscopy with the feel of open surgery,” says Krummel. “It puts a smile on your face.”

Anticipated technological advances, such as tactile feedback more sensitive than a human hand or the incorporation of X-rays into the surgeon’s field of vision, might compensate for the new distance between doctor and patient.

“The future will involve some interface between man and monster, so to speak, that will allow us to do more from a distance than we can do ourselves,” says Albanese. When that happens, surgeons may come full circle, realizing that those steps away from the operating table offer an intimacy — and an opportunity for good medicine — that would have left their predecessors astonished and envious. SM

Robots: The next generation turning science fiction into fact

Kenneth Salisbury and Thomas Krummel have great imaginations. The two Stanford professors are putting their heads together, along with some funding from the National Institutes of Health and Stanford’s Bio-X interdisciplinary research fund, to dream up the next generation of surgical robots. What they envision will expand the boundaries of surgery beyond what most people can conceptualize.

 

Kenneth Salisbury, PhD, (left) robotics expert, and Thomas Krummel, MD, chair of surgery, are creating tools to amplify a surgeon's sense of touch.

“Fantasies in science fiction like The Incredible Voyage inspire us,” says Salisbury, professor of computer science and of surgery, “and these visions can sometimes come true.”

Salisbury collaborated with researchers at Intuitive Surgical Inc. to address one of the most difficult limitations of laparoscopic surgery: the relatively limited range of movements of the long, slender instruments. The “wrist” that the company’s da Vinci surgical robot now uses sports six ranges of movement. It gives the human wrist, which has seven ranges of motion, a run for its money. Now they’d like to develop a method to translate the tactile sensations experienced by the instruments inside the patients to the control handles held by the surgeon. But it’s a difficult proposition.

“We’re pretty good at synthesizing how virtual things feel when you touch them; we can make something we want to feel squishy, feel squishy,” says Salisbury. “But it’s much more difficult to first accurately detect the feel of an actual organ and then transmit that faithfully to the surgeon’s hands.”

Their plans remain ambitious, though. Salisbury envisions tactile feedback so sensitive that it actually surpasses what a surgeon would normally be capable of feeling with a gloved hand.

“With mechanical improvements the fidelity of feedback should get really good,” says Salisbury. “It may be possible to have touch feedback that is better than normal, just like microphones and microscopes enhance hearing and vision.” He’s also interested in developing ways to flag danger areas, such as a nearby artery or vital organ, as out-of-bounds for surgery.

“By mapping points three-dimensionally within the body, we could develop a virtual no-fly zone that could be translated to the surgeon, perhaps by vibration of the controls or an inability to enter that area.” Such mapping, which is already possible, could also be used to superimpose other types of navigational or physiological information, such as previously obtained ultrasound images or X-rays.

“We may also one day be able to include information about chemical or electrical activity in the surgical area in the surgeon’s field of vision,” says Salisbury. Biochemical markers could be used to identify unseen infection or hidden tumors.

Surgical simulations involving robots could allow doctors to rehearse an operation for an individual patient after loading all the relevant data into the simulation system.

“We have to figure out how to make computer models of complicated things like organs,” says Krummel, chairman of Stanford’s surgery department. “Ten years from now, we may be able to practice on a patient using a CT scan. Once we get it right, we could deliver the data set of that correctly done procedure to the robot. In this way, a surgeon could practice a procedure many times before operating on a real patient — a remarkable advance in surgical training that gives people the freedom to fail.” Programming such simulations with hidden dangers, such as an unexpected hemorrhage or cardiac arrest, could also prove an effective training tool.

Finally, surgical robots could allow physicians to collaborate on complex cases. A more experienced surgeon at a remote console could comment, answer questions or even help hold instruments or demonstrate techniques.

“Our goal is always to provide not just the state of the art, but the next iteration,” says Krummel. “Now we’re asking ourselves how to make surgical robots one-quarter of the current size and one-tenth of the cost. We’d also like to develop new tool tips for better control of bleeding and for suturing. The future isn’t something that just happens — we’re inventing it.” — Krista Conger

Comments? Contact Stanford Medicine at

 Back To Contents