The STAR robot has performed operations on soft tissue with greater precision than a human surgeon – and entirely autonomously. An innovative tracking system allows it to compensate for any movements during the operation, such as in the muscle itself.
The use of robotic systems in operations is no longer something new; the da Vinci Surgical System has been used in hospitals around the world for several years already, to name just one example. Until now, however, the machines have still been controlled by doctors, making the systems in use little more than remote-controlled tools. Yet now there is a robot which can perform operations autonomously – that is to say, it does not require any input from doctors. The “Smart Tissue Autonomous Robot” (STAR) developed by researchers at the Children’s National Health System in the USA is even able to operate with greater precision than a human surgeon. While the robot needed more time to fulfil the task than its human counterpart, the results were extremely impressive. Surgeons and scientists from the Sheikh Zayed Institute in Washington demonstrated the robot’s capabilities during operations on dead pig tissue and living animals. STAR planned and implemented the suture autonomously under the watchful eye of a doctor.
Improving the quality of operations
STAR was specifically developed to operate on soft tissue such as muscles, tendons, ligaments, nerves, blood vessels and connective tissue. Around 44.5 million surgical procedures are currently carried out on soft tissue every year in the USA. “Our results demonstrate the potential for autonomous robots to improve the efficacy, consistency, functional outcome and accessibility of surgical techniques,” says Dr Peter C. Kim, Vice President and Associate Surgeon-in-Chief, Sheikh Zayed Institute for Pediatric Surgical Innovation. “The intent of this demonstration is not to replace surgeons, but to expand human capacity and capability through enhanced vision, dexterity and complementary machine intelligence for improved surgical outcomes.”
Previously, operations on soft tissue were entirely manual activities and were not able to be supported by robots. The main reason for this is that operations on soft tissue constantly entail unpredictable, elastic and plastic changes which require continuous adaptations on the part of the surgeons.
The system adapts in real time
STAR solves this problem with the help of a tracking system that combines near-infrared fluorescence markers and 3D light-field cameras. Plenoptic cameras also record the direction of incident light rays alongside the usual two image dimensions. This additional dimension affords plenoptic images extra information about the picture depth. Using this system, it is possible to precisely detect any movements and changes in the tissue in the course of the surgical procedure. The tracking system is combined with a smart algorithm which guides and controls the procedure, all the while performing real-time adaptations to changes in the tissue. What’s more, STAR is equipped with pressure-sensitive sensors, sub-millimetre positioning and powered surgical tools. Its robotic arm features a lightweight construction that permits movements with eight degrees of freedom.
Now that the robot has proven its efficacy, Dr Kim says that the next step is to reduce the size of the surgical tools further and improve the sensors in order to expand the range of application for the STAR system. He anticipates that the system – or certain aspects of the technology – could be ready for use in hospitals within two years.