STAR sutures a live pig's intestine by itself
On 4 May 2016 a group at Children's National in Washington published in Science Translational Medicine the results of operations in which the robot STAR (Smart Tissue Autonomous Robot) planned and placed the stitches on an intestine by itself, with the surgeon only supervising. It performed four intestinal anastomoses on living pigs, and all the animals survived without complications.
Why it matters
Until then autonomous surgical robots had worked only on rigid tissue such as bone, which does not move during an operation. STAR was the first to do it on the soft tissue of a live animal, tracking how the tissue shifts and deforms and changing its plan as it went. This is an editorial assessment. The work showed that autonomy is possible exactly where a surgeon had so far had to keep adjusting by hand.
How it works. A lightweight robot arm with an articulated laparoscopic suturing tool, eight degrees of freedom in all. It sees the tissue through a plenoptic 3D camera and near-infrared fluorescent markers placed on the tissue, and has force sensing. The program draws up a plan of stitches and changes it when the tissue moves. The comparison. On pig tissue outside the body the tasks were a linear suture and joining two ends of an intestine, compared with an experienced surgeon suturing by hand, with laparoscopy and with a surgeon-controlled da Vinci robot. On living pigs the comparison was with the same operation done by a surgeon with standard tools. STAR was better at even stitch spacing and at the pressure at which the joint begins to leak, and made few mistakes that required pulling the needle out. Time. The surgeon took 8 minutes; the fastest STAR operation took 35. The authors note that a clinical laparoscopic anastomosis takes 30 to 90 minutes. What the record does not claim. The full article was not read, behind a Cloudflare check: the abstract comes from Europe PMC, and the number of pigs and the times from the institution's press release. The operation was done with the abdomen opened, not laparoscopically. STAR did not operate on people.