© Johns Hopkins University/PAThe Smart Tissue Autonomous Robot can perform laparoscopic surgery on the soft tissue of a pig without human help.
The robot surgeon will see you now.

For years, the world of medicine has been steadily advancing the art of robot-assisted procedures, enabling doctors to enhance their technique inside the operating theatre.

Now US researchers say a robot has successfully performed keyhole surgery on pigs all on its own - without the guiding hand of a human. Furthermore, they add, the robot surgeon produced "significantly better" results than humans.

The breakthrough is another step towards the day when fully automated surgery can be performed on patients.

The Smart Tissue Autonomous Robot (Star) carried out laparoscopic surgery to connect two ends of an intestine in four pigs. According to a paper published in Science Robotics, the robot excelled at the procedure, which requires a high level of precision and repetitive movements.

Axel Krieger, of Johns Hopkins University, said it marked the first time a robot had performed laparoscopic surgery without human help.
"Our findings show that we can automate one of the most intricate and delicate tasks in surgery: the reconnection of two ends of an intestine. The Star performed the procedure in four animals and it produced significantly better results than humans performing the same procedure."
Connecting two ends of an intestine is a challenging procedure in gastrointestinal surgery, requiring a surgeon to apply stitches - or sutures - with high accuracy and consistency. Even a slight hand tremor or misplaced stitch can result in a leak that could result in a patient suffering fatal complications.

Krieger, an assistant professor of mechanical engineering at Johns Hopkins, helped create the robot, a vision-guided system designed specifically to suture soft tissue. It improves a 2016 model that repaired a pig's intestines, but required a large incision to access the intestine and more guidance from humans.

Experts say new features allow for improved surgical precision, including specialised suturing tools and imaging systems that provide more accurate visualisations of the surgical field.

It is hard for robots to perform soft-tissue surgery because of how unpredictable it can be, forcing them to be able to adapt quickly to handle unexpected obstacles. The paper set out a novel control system in the Star that can adjust the surgical plan in real time, just as a human surgeon would. Krieger said:
"What makes the Star special is that it is the first robotic system to plan, adapt, and execute a surgical plan in soft tissue with minimal human intervention. Robotic anastomosis (surgically joining two structures) is one way to ensure that surgical tasks that require high precision and repeatability can be performed with more accuracy and precision in every patient independent of surgeon skill. We hypothesise that this will result in a democratised surgical approach to patient care with more predictable and consistent patient outcomes."