On 13 October 2015, KCL, EAES, PIAP, SSSA and UNITO representatives met at the Institute for Medical Sciences and Technology (IMSaT) in Dundee, UK, for a one-day session on human cadavers. The team of engineers installed the entire STIFF-FLOP system including a multi-segment octopus-like robot equipped with a camera and associated software. At IMSaT all cadavers are routinely prepared by the so-called Thiel method which preserves humans in a very life-like, realistic state with regards to appearance and mechanical soft tissue properties.
On the day of the trial, the surgical team operated on two human cadavers that had been selected and prepared by the STIFF-FLOP team during a preparatory session at IMSaT in September 2015 and operated for the first time on a human body using a soft surgical robot as part of keyhole surgery, with the aim of dramatically improving future surgical practice.
Four trocars were used to perform a minimally invasive total mesorectal excision. The flexible STIFF-FLOP camera robot (2-segment STIFF-FLOP arm with camera integrated at the tip) was inserted via a commercially-available 15-mm trocar in the patient on the median line about 2 cm above the umbilicus. In addition, a standard rigid 30-degree laparoscopic camera was inserted through a 10 mm trocar posterior to the STIFF-FLOP camera to observe the motion behaviour and functionality of our STIFF-FLOP camera arm.
The lateral bending movements and the elongation of the robot camera were controlled by the surgeons using a dedicated input device with assistance by an engineer for elongation and retraction.
The use of the STIFF-FLOP camera first allowed the surgeon to
a) clear-ly recognize the inferior mesenteric vessels that were divided and the autonomic nerves that were spared and
b) dissect the sigmoid mesocolon.
Then, the ability to follow smoothly the sacral curve when dissecting the posterior mesorectum or to overtake the rectum when dissecting the left mesorectum, due to the flexibility of the modules and the magnified vision provided by the STIFF-FLOP robot camera allowed the surgeons to perform a very precise dissection of the entire mesorectum. The same procedure was performed on two human cadavers, demonstrating the feasibility of the system. The overall operative time for both procedures was about 3 hours with no intraoperative complications or mechanical problems related to the use of the STIFF-FLOP robotic technology. The session proved to be very successful, clearly showing the feasibility of soft robotics for minimally invasive surgery (MIS).