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An Autonomous Robot Successfully Performed Surgery on a Pig

A robot just demonstrated it could perform soft tissue surgery with minimal supervision.
May 4, 2016, 6:00pm
Researchers working with the STAR robot. Image: Dr. Axel Krieger

A robot just demonstrated it could perform soft tissue surgery with minimal supervision.

Over 45 million soft tissue surgeries are performed each year in the United States alone. Soft tissue is challenging even for the most skilled surgeon. Due to its malleable and unpredictable nature, researchers weren't convinced that robots could work with soft tissue. Until now.

Researchers from the Children's National Health System in Washington, DC are hoping their new Star robot, which stands for Smart Tissue Autonomous Robot, will be the next great tool in a surgeon's arsenal. As surgical tools become smarter, they will work with surgeons to mitigate complications and provide better outcomes.


The STAR robot securing sutures with a human assistant. Image: Sheikh Zayed Institute for Pediatric Surgical Innovation

The team of researchers, lead by Azad Shademan, developed the STAR robot to perform complex surgical tasks, in this case reconnecting pig bowel segments. Equipped with a robotic arm and surgical tools, the STAR robot performed the procedure under the supervision of a human surgeon. The research was published Wednesday in the journal of Science Translational Medicine.

"The surgeon can stop robot at any time and take over," explained Shademan. "The surgeon will closely monitor the robot and in case something critical happens, they are a finger press away from taking over."

Officially known as an intestinal anastomosis, the procedure involves connecting two tubular sections of intestines, much like putting together garden hose that's been cut. Consistency in spacing and tension are key. You want a hose (or in this case, bowel) to be strong enough so when the pressure increases in the hose, it will not leak.

The researchers performed two different procedures, one ex vivo and one in vivo, connecting two segments of a pig's bowel. The procedure was fully autonomous, meaning it was programmed into the robot and the surgeons were only there to supervise, much like a parent supervises their child's first steps. Both procedures were a success and the pigs showed no signs of complications.

What makes this procedure unique is that the robot relied on a special infrared camera system, much like night vision. Fluorescing biomarkers were added to the tissue to highlight the surgical field and guide the robot.


The robot's techniques were then pitted against human surgeons and current robot-assisted techniques. The results showed that the STAR robot outperformed both the human surgeons and current robotic techniques. The suture spacing and tension were consistent, indicating that this technology would be a major benefit.

"To test it, we essentially took the bowel, connected it to a pump, and increased the pressure until it leaked," explained Ryan Decker, a researcher on the study. "The procedure performed by the STAR robots measured a higher bursting pressure than humans."

The data also shows that the robots consistently performed better than the surgeons alone. "For example, let's say humans do 19 out of 20 things very well, but that last one could be where the complications arise," explained Peter C. W. Kim. "By making procedures more intelligent, we can ensure better outcomes for patients."

The STAR ring where surgeries are performed. Image: Carla Schaffer/AAAS

Robot-assisted surgical techniques are nothing new, as platforms like the Da Vinci surgical system have enabled surgeons to perform minimally invasive procedures while providing enhanced technologies.

However, the current systems in place are guided by the surgeons, and essentially take their motions and translate them into precise motions with tiny instruments. Surgeries performed with this technology rely on the technique and skill level of the surgeon. Da Vinci cannot compensate for an unskilled surgeon. STAR is programmed with the best techniques and removes human error from the procedure.

The team stresses that they are not trying to replace surgeons. The idea behind this technology is based on the same reasons why we have driverless cars: not because we can't drive, but to reduce accidents.

Now that the robots have demonstrated they can put things together, future tests could involve taking things out, like gallbladders or tumors.