Researchers have programmed a robot to sew up intestines autonomously, with more precision than the typical human surgeon achieves. Right now, the intestines happen to be inside pigs, but some aspects of the technology could soon be used on humans.
“Within the next couple of years, I expect that as surgical tools become smarter, it will inform and work with surgeons in supporting better outcomes,” Peter Kim, a researcher at the Children’s National Health System in Washington, D.C., told reporters this week.
Kim and his colleagues describe their surgical system – known as the Smart Tissue Autonomous Robot, or STAR – in a paper published online today by Science Translational Medicine.
Surgical robots have been around for a long time, but so far they’ve been used as tools rather than taking on medical tasks on their own. The surgeon typically manipulates the robot’s instruments in real time, in some cases guided by a video feed.
STAR combines a number of technologies that are already in use, including the KUKA robotic arm, and adds a layer of programming that translates near-infrared imagery of the surgical site into a course of action. When the human surgeon presses a button, the STAR robot executes a program to stitch up a break in the intestines.
Kim calls the machine a “very advanced, smart sewing machine.”
Under the watchful eyes of surgeons, STAR took on a series of suturing assignments, starting with pig cadavers and ending up with operations on four live piglets. In each case, the surgeons opened up the abdomen, sliced open the small intestine, and placed a pattern of guide markers on the cut ends with paint that glowed in the near-infrared spectrum.
The robot sized up the situation based on the markers, and then developed its own procedure for suturing the cut ends together – a procedure that’s known as anastomosis. About 40 percent of the time, the surgeons tweaked the program for the procedure. The other 60 percent of the time, the robot went ahead with full autonomy.
The metrics for the resulting sutures were compared with the statistics for experienced human surgeons who used standard clinical techniques, including the current tools for robot-assisted surgery. By most measures, including the spacing of stitches and the tension on the sutures, STAR did better. Its mistake rate was comparable to hand-sewn suturing.
The most notable exception had to do with speed: The robot took more than 20 minutes to perform a procedure that would take a human less than 10 minutes to do by hand. However, Kim said time was not of the essence for the proof-of-concept experiment. “I’m sure that as the technology matures, if you let it run fully autonomously, it would be significantly faster,” he said.
Blake Hannaford, director of the University of Washington’s Biorobotics Laboratory, said the experiment marked a “technical breakthrough” for surgical robotics. Hannaford and his colleagues are working on an open-source platform for robot-assisted surgery known as RAVEN.
In an email to GeekWire, Hannaford also noted that the newly published work had “clear limitations which show that automation assistance will not come to the operating room soon.” For example, humans still had to identify and mark the targets for sutures.
“While in a technical sense, semi-autonomous suturing is a ‘grand challenge’ problem of surgical robotics, clinically much suturing and bowel anastomosis is done by staplers which can do the whole thing in seconds,” Hannaford wrote. “Clearly the task they chose does not justify the elaborate equipment they used. Nevertheless, the paper is a breakthrough that shows supervised autonomy could be safe and effective.”
Several patents have been filed related to the technology, and Kim has created a startup called Omniboros to develop surgical robots. “With the right partner, some or all of this technology can be incorporated into commercially available, clinically applicable tools, probably within the next two, no more than three years,” he said.
In the near term, surgical robots could incorporate the techniques used by the best surgeons and make them available more widely, and potentially less expensively. “If you can say it saves half an hour, that in itself will have a significant impact on your overall healthcare costs,” Kim said.
In the longer term, autonomous robot surgeons could play a key role in isolated environments ranging from Antarctica, where physicians have had to heal themselves, to humanity’s future outposts in deep space. Kim cited SpaceX founder Elon Musk’s plan to colonize Mars as an example.
“It’s like life imitating art,” he said. “You’ve seen the movie where you have this medical pod. That was the whole notion behind the initial DARPA investment for surgical robots in the battlefield, as a trauma pod. … You can imagine a medical pod or surgical pod that can accomplish this specific task.”
Azad Shademan of the Sheikh Zayed Institute for Pediatric Surgical Innovation at Children’s National Health System is the first author of the Science paper, “Supervised Autonomous Robotic Soft Tissue Surgery,” Kim is the corresponding author. Other authors include Ryan Decker, Justin Opfermann, Simon Leonard and Axel Krieger.