Robotic surgery: how does it work ?

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The Robot Will See You Now
In Sunnyvale, Intuitive Surgical is piecing together the robot surgeon of the future :

A News by By Gary Singh (2004):

"TUBES, intricate robotic parts and medical machinery fill the room as I sneak a glimpse from outside. The door is open, but I'm not allowed to go in. A funny odor somewhere between formaldehyde and soap floats out of the room. Off in the back of Intuitive Surgical's air-conditioned Sunnyvale offices, the room connects to another room, also off-limits to the public. Inside, doctors are training on the da Vinci robotic surgical system, although I can't see what they're up to.

Intuitive hopes to revolutionize the process of Minimally Invasive Surgery (MIS).
Their plan of attack: have a robot perform operations.



In conventional MIS, the surgeon manipulates a long skinny camera called a laparoscope and a few other chopsticklike instruments that are stuck through tiny incisions in the body. The instruments basically serve as pivot points; in order to move the scalpel down, the doctor has to move the instrument up and vice-versa. And since the surgeon watches the piped-in video on a monitor, the entire process is difficult and counterintuitive. Physicians must go through special training to perform this kind of operation.

Named after famed artist and scientist Leonardo da Vinci, who laid out plans for the first robot, Intuitive's robotic system works like this: The doctor sits at an ergonomically designed console, almost like a sit-down arcade game from the 1980s, and remotely operates three skinny cylindrical robotic arms that perform the surgery with minute scissors, clamps and other proprietary EndoWrist instruments.

The robotic arms pierce the patient's body through tiny dime-size incisions the doctors make by hand. As if playing castanets, the surgeon uses his wrists, thumbs and forefingers to control the instruments on the ends of the robotic arms. Wires connect the console to the robot, the base of which rises up from the floor and spreads out over the operating table like a giant metal spider.

The surgical arms themselves then spring from the base and can be manipulated into just about every possible position or angle. A foot pedal controls a camera that shoots back high-quality video, giving the doctor an enlarged 3-D view—almost like being inside the patient himself. The entire system allows the surgeon to grasp, graft and clamp with more precision and more detail than was previously possible.

As the surgeon twists the controls, the robot's instruments twist exactly the same way, giving the doctor a natural and precise hand-eye coordination. The video is also transmitted to a huge monitor, allowing the rest of the surgical team to see how the operation is proceeding.

Since the da Vinci System is not autonomous and independent, you can't call it a true "robot" per se. It doesn't really have a mind of its own. The doctor runs all the controls. It's not like C3PO is donning hospital whites and operating on a living human. It's a master/slave situation, with the surgeon as the master.

The $1.5 million system is starting to pop up in all sorts of places. It made a cameo appearance in the last James Bond flick, Die Another Day, and a modified version also shows up for eight seconds in The Stepford Wives. Just recently, the surgical robot appeared on The Today Show. And you have to admit that the term "RoboSurgeon" absolutely has a ring to it. Igor and Dr. Frankenstein would be proud.

That's the Future

With the da Vinci system, doctors can perform coronary-bypass surgery without having to crack open the chest and use a heart-lung machine to circulate the blood and oxygen—one of the main problems of cardiac surgery.

Due to the reduced invasion of the body, patients tend to recover much more quickly. As a result, the cost can be reduced dramatically. Folks undergo heart surgery and can return to work a few weeks later. There's much less trauma after the fact—and no huge ugly scars. There's nowhere near as much blood loss or infection.

Fawaz Khanachet, a construction project manager for Alameda County, underwent a prostatectomy with the da Vinci System and was out of the hospital in fewer than 48 hours. He went back to work two weeks after the surgery.

"The recovery was relatively quick", he recalls. "There was very little discomfort when I got home".

Any surgery is both patient- and procedure-specific. There are no absolute guarantees. According to the summer 2003 issue of Intuitive's aptly titled newsletter, Robotic Surgeons Quarterly, 193 patients underwent a minimally invasive robotic procedure between October 2000 and November 2002 at one particular hospital in Italy. Three of them didn't make it.

But that's not necessarily a bad statistic. A number of issues contribute to overall mortality rates in various kinds of surgery—patient history, patient-to-nurse ratios and the type of surgery being performed, to name but a few—and various studies have shown mortality rates range from 1 percent to about 6 percent in general.

Remember that one story about a doctor accidentally leaving his wristwatch inside a patients' body? Well, that isn't supposed to happen with the da Vinci system. Gaping incisions are no longer necessary. And surprisingly, patients don't seem to mind going beneath the robotic tools.

"I thought when I first started using this robot on people that there would be a lot of hesitancy about it," says Dr. Barry Gardiner of the San Ramon Regional Medical Center. "Contrary to what I expected, it's been very, very seldom that we've had a patient express a concern about being operated on with this device. The patients look at it, and they hear the surgeons explaining to them that it enhances their surgical capabilities, it enhances dexterity and flexibility and control and vision, rather than negatively impacting it. It positively impacts it. So most patients have no problem being operated on. In general, the patients have received it very, very well, and that has not been an issue."

Khanachet felt the system was very advanced and even futuristic. "I thought, 10, 20, years from now, everything will be done with the aid of robots and robotic instruments," he says. "I did not have very much reservations about it. I thought, 'That's the future, and it's now.'"

Failing Safely

Just the idea of a robot operating on a human might give some surgeons a case of either the jitters or ruffled professional feathers. Many doctors are proud of their skills and feel they just don't need a contraption to perform an operation they can already perform themselves. Plus, at $1.5 million, one has to wonder if the machine is cost effective or not.

Pediatric surgeon Thomas M. Krummel of Stanford Hospital negotiated the purchase of a da Vinci System and, along with his partner, Craig Albanese, was the first one there to use it.

He wouldn't comment for sure whether or not it was worth the price. "I think it depends on how you define 'worth the price,'" he ventures. "There are some institutions who want to be on the leading or, you might even say the bleeding edge, and I think it makes sense for those institutions to use, study and evaluate new technologies. Or those that run a very small practice that doesn't have a lot of cases that need a robot, [then it] probably doesn't make sense. I think it's all about selection."

Skepticism is justified, primarily for safety concerns. One has to wonder what would happen should the machine break down during an operation. Is there a backup? What would the patient's chances for recovery be?

"The system is very robust at failure," explains Dave Rose, Intuitive Surgical's senior director of Robotic Systems Marketing. "If it fails, it fails safely."

I'll have to take his word for it, as several safety precautions are indeed built into the system. To cite just one example, the system features motion-scaling technology to filter out any shakiness of the surgeon's hands. This is accomplished by requiring the physician to move his hand around 10 times farther than he normally would to perform a stitch or a suture. His movement is scaled down, so the tip of the instrument moves proportionately 1/10 as much as the doctor's hands do.

"If you're trying to do a very precise movement, in which you're moving only 1 millimeter, holding that kind of precision with your hand is quite complicated," says Pablo Garcia, a senior research scientist at SRI International, who works with technology on which the da Vinci System is based.

"It requires a lot of dexterity," he explains. "If you scale the movement, you can do a 10-millimeter movement with your hand and end up with only a small displacement on the robot side. It's like changing the scaling in the mouse on your computer. You can do a finer control, where a small movement on the pad results in a big movement on the screen, or the opposite, like in this case, where a big movement on the pad results in a small movement on the cursor. That's the idea."

Garcia says that we all have a natural tremor in our hands, and it can be viewed under a microscope. Since it's a precise frequency, the robot can filter it out. "When you filter it through the robot, you don't notice any vibration at all," he explains.

So if the doc had a little too much coffee that morning, the robot will compensate for it.

Paul Lilagan, a product manager and clinical engineer at Intuitive, adds that a full redundant safety system is a major component: "In each joint, there are sensors that record the position of those joints. And the system checks that positioning over 1,300 times a second just to make sure that the position between the two redundant sensors is correct. It monitors all the motors that drive all the different parts, the wrists, and everything else ... to make sure they're functioning properly. And all the electronic boards that drive the entire system are also constantly being monitored. Along with the system network, there's a second safety network that's monitoring whether everything's working right."

So no worries, he appears to be saying. The robotic arm won't snap off inside your body.

"The FDA approval process is enormously focused on mechanical safety and security associated with using the device," Krummel continues. "We've never had any mechanical problem whatsoever."

Gardiner also says that he has performed almost a thousand operations with the system and witnessed only two mechanical failures. "One time, the system went down just as we were finishing the operation, so it wasn't an issue," he explains. "The other time it just wouldn't boot up, so we never even got started with the operation. So there's never been an issue that affected or impacted patient care in any way, as far as I'm aware of."

If there exists any sort of mechanical problem, the machine won't even boot up. The safety network will prevent it from going forward with the startup process. If something does go wrong, repair technicians are only a phone call away, and tech-support junkies likewise staff the phones round the clock.

Off to the Races

Local MDs Fred Moll and John Freund, along with electrical engineer and Hewlett-Packard manager Robert Younge, founded Intuitive Surgical in December 1995 in Sunnyvale. The da Vinci system can be traced back to Phillip Green's original work at SRI in the late 1980s. Green originally received a grant from the National Institute of Health to design prototypes for future models of computer-assisted laparoscopic surgery.

Moll originally checked out one of the prototypes at SRI in 1995 and then hooked up with Younge and Freund to start the company. Intuitive Surgical licensed the basic patents from SRI, added some of its own proprietary technologies and collaborated with IBM, MIT and other groups. As a result, they led the way to the first commercial form of robotic-assisted surgery.

"Like a lot of these things, you need a champion behind it," Garcia tells me. "Fred Moll was the surgeon who got interested in the technology. [He] thought it had a lot of potential and got investors interested as well."

The first systems were used in Europe; after FDA approval, the machines were allowed in America. In August 1999, the first system in the United States was installed at Ohio State University. The IPO hit home in June of 2000 with 5 million shares, and Intuitive was off to the races. There are now more than 200 Vinci Systems around the globe in various academic and community hospital settings, including Stanford Hospital, Alta Bates Hospital in Oakland and Washington Towneship Hospital in Fremont.

In March of 2003, Intuitive Surgical ranked 31st in the Silicon Valley/San Jose Business Journal's 50 fastest-growing public companies. For the first quarter of 2004, its profits increased 41 percent from a year ago, and the company now has more than 300 employees.

Intuitive also recently bought out its major competitor, ComputerMotion, the manufacturer of the Zeus robotic surgery machine. Zeus' hardware was fundamentally similar, but unlike the da Vinci system, the surgeon sat opposite a vertical screen, as opposed to da Vinci's immersive monitors embedded in the eyepieces of the visor port. The da Vinci System also has an extra degree of freedom in the hand controllers.

The system is not without drawbacks, however. Its $1.5 million price tag puts it completely out of the reach of most hospitals. "It's got a long way to go," Moll explained at the American College of Surgeons' annual meeting in October of 2001. "It's too big. It's too expensive. It doesn't have all the tools surgeons need."

Garcia agrees. "It's still just the Formula One version," he says. "They need to get to the passenger Toyota car that everybody can use."

Krummel concurs that the machine is too overwhelming. "If you're operating on 6-pound babies, it's a pretty big device," he said.

I, Robot Doc

Over in the lobby of Intuitive's glossy headquarters, a promo video at the front desk shows the da Vinci System performing surgery, definitely not footage for weak stomachs. Press clippings from around the globe grace the walls as you waltz down the hallway from the lobby to the demonstration room. You feel like you're at the worldwide center of medical innovation, in some strange mad-scientist sort of way.

And speaking of mad scientists, sitting down at the da Vinci System's console has a pure godlike vibe. It's like being in sole charge of a seven-figure pair of pliers.

You also just can't ignore the B-movie aura about the whole thing. At the console, you feel like Vincent Price playing organ in The Abominable Dr. Phibes. The automated domestic assistants in I, Robot come to mind immediately. And you can easily picture a scene where the robot suddenly comes alive and starts operating on you instead.

All horror aside, surgeons from all over the country come to Intuitive's headquarters to train on the machine. Sometimes they even practice on cadavers with fake blood—the medical equivalent of flight simulation.

Ever wanted to pretend like you're in the operating room suturing or sewing stitches? This is the place. Looking into the console's eyepiece at a close-up view of the EndoWrist instruments, it really feels like you're able to shrink your hands and put them in places they'd never ordinarily fit.

Which is word for word how Gardiner described the process in a Time magazine article on June 4, 2001. Gardiner was one the key players in the original design of the da Vinci System, and he collaborated with the original founders and engineers. He even relocated his practice to San Ramon just to start its robotic surgery program, and his machine was the first one west of the Mississippi.

"It's a device that we initially designed to provide the surgeons with the technical capabilities that they had with open surgeries that they lost when the laparoscope came into being," he says. "The laparoscope, although it had an advantage of limiting the size of the incisions, it also limited the surgeon's visibility because they had a two-dimensional image. It limited flexibility and dexterity because you're operating with a long-shafted instrument that is rigid and had no articulation in it. So what we tried to do was return those aspects of surgery back into the laparoscopic arena that you couldn't do with conventional laparoscopy. And the way that was done was by basically introducing a computer between the end of the instrument and the surgeon's hands."

Long-Distance Checkups

Looking to the future, Lilagan explains that Intuitive is always seeking to add additional clinical capabilities to the system: "Recently, we've added a fourth arm to the system, which actually now provides the surgeon sitting at the console to have control of an extra hand, which would normally be—either in a laparoscopic case or an open case—the assistant's hand. We're trying to give more control to the console surgeon to be able do his surgery. ...We're really just across the board trying to figure out where we can add value to the surgery."

SRI also conducted research for the Defense Department on how to use robots to remotely operate on soldiers in the battlefield, and Garcia says remote surgery has already been performed in Canada. So one can also imagine someday seeing a doctor in San Francisco assisting on surgery in Tokyo. Or when astronauts finally make it to Mars, a surgeon might need to remotely operate on them should they get injured.

But this is all still years away, as the speed of communication channels just isn't there yet. The lag time between the surgeon's movements and the actual remote robot's maneuvering on Mars is still significant over long-distance connections, so we probably won't see such scenarios until decades down the road.

Lilagan says Intuitive is aware of these directions, but they are not necessarily a focus. There are many obstacles to overcome that aren't under Intuitive's control, and he says the company is taking a much smaller-step approach to advancing the technology. "[For telesurgery] we would need to have a fiber-optic lead and we need to know which surgeon would be held responsible for the surgery, and there's legal matters. ...That really is farther down the line, and the rate [at which we get there] is going to be dependent on other technology."

Garcia says the technology for remote surgery is definitely here, but SRI's adds that research is geared more toward widening the robot's availability.

"It's more a matter of whether the market really needs remote applications or not," he explains. "I would say a lot of the research is going towards making smaller tools, making them capable, more dexterous, making the whole robot smaller, cheaper, easier to set up, friendlier, so that it doesn't require as much overhead to operate. ...That's where a lot of the focus is, on finding surgeries where [the robot] really has a benefit. For example, an area we're looking more into is pediatric, neonatal, fetal surgery, areas of surgery that traditionally have been very difficult for surgeons to perform, where there are still a very limited number of procedures, but still have a lot of potential."

Krummel agrees that the robot will eventually become smaller: "One-quarter the size and a fraction of the cost would make it broadly applicable. We have an active robotics research program that is trying to sort out how such things might be built into or used to scale down the device."

In the end, because of or despite the B-movie mad-scientist aspect of it all, even children get a kick out of test-driving the da Vinci System.

'When we have people come in with their kids, and the kids sit down with the machine, they're not thinking about all the stuff behind it," Lilagan said. "It's just play. And some of the surgeons look at it that way too. It's fun. Overall the main goal is just to do better surgery.'"

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