An autonomous robot has performed surgery on a pig’s intestine, resulting for the first time in better results than a human surgeon.
A team from the Children's National Medical Center in Washington DC, the US, has built the Smart Tissue Autonomous Robot (STAR) with the goal to reduce complications caused by human error.
Unlike current medical robotics, such as the da Vinci Surgical System, which requires the human surgeon to manually guide the robotic arm, STAR was programmed ahead of the procedure, which it then performed autonomously, with only limited supervision from the researchers.
“It was about 60 per cent fully autonomous and 40 per cent supervised,” said Peter Kim, who led the study. “We made some minor adjustments in the process, very much like when you see a little baby trying to walk and everyone is a little nervous about it to make sure that it does it the right way, but it can be fully autonomous for the task that we are trying to do.”
The procedure on which the researchers decided to test the robot is called anastomosis and involves connecting two bowel segments. After practicing on pieces of dead gut, the robot flexed its muscles operating on a pig.
The animal patient not only survived, but its gut was also stitched together better than that of other animals that underwent the same operation by a human operator, either as an open surgery or laparoscopy, or performed by a semi-autonomous robot.
Fully autonomous robots have previously been used in hard-tissue surgeries, such as in bone cutting. However, the robots have struggled with soft tissue, which reacts in unpredictable ways.
STAR, which has been described as an ultra-smart sewing machine, is fitted with a 3D imaging system and a near infrared sensor that detects fluorescent markers, which tell the robot where sutures have to be made. The team took four years to create and program the robot. It took inspiration from suturing techniques of the world’s best human surgeons.
“When compared to current standards of practice, the machine does it better,” Kim said. “If you have 20 stitches, it’s not enough when a human being does 19 out of 20 well. You need to have all 20 of them well to have a good outcome. This machine will consistently throw 20 perfect sutures.”
The only downside, the researchers admitted, is that the robot in its current incarnation, works considerably slower. While a human operator performing an open surgery would be done in eight minutes, STAR stitched its way through the task meticulously in 35 to 57 minutes.
In future, the robot could assist with tumour removals, appendectomies and other types of soft tissue surgery.
“Just imagine having the best technology and technique available any time, any place, to any surgeon and any patient,” said Alex Krieger from the Children's National Medical Center.
“Having these intelligent systems and working with surgeons will ultimately decrease complications and provide better outcome and safe lives.”
Imperfect suturing can lead to problems such as bowel leakage, which according to estimates occurs in 25 to 30 per cent of cases of abdominal surgeries.
The study was described in the latest issue of the journal Science Translational Medicine.