The current state of miniature in vivo laparoscopic robotics.

Minimally invasive surgery (MIS) reduces patient trauma and shortens recovery time, but also limits the dexterity of the surgeon because degrees of freedom are lost due to the fulcrum effect of the entry incisions. Visual feedback is also limited by the laparoscope, which typically provides two-dimensional feedback and is constrained by the entry incision. Developments within surgical robotics aim to mitigate these constraints. However, these developments have primarily included large external machines that augment vision and improve dexterity, but are still fundamentally constrained by the use of long tools through small incisions. An alternative concept is the use of miniature in vivo surgical robots that can be placed entirely into the peritoneal cavity through either an abdominal incision, or, after insertion into the stomach through the esophagus, can enter through a gastrotomy. This paper reviews the development of fixed-base camera robots for providing auxiliary views of the surgical field and of mobile robots with a movable platform for vision and task assistance in laparoscopic procedures. Moreover, the progress towards the application of similar robots for natural orifice transluminal endoscopic surgery (NOTES) and forward environments is discussed.