Magnetically Activated Stereoscopic Vision System for Laparoendoscopic Single-Site Surgery

In this paper, the authors present an innovative vision platform for laparoendoscopic single-site (LESS) surgery based on a wired and magnetically activated 5-degrees-of-freedom robot with stereovision. The stereoscopic vision module, developed using two off-the-shelf cameras and a light emitting diodes lighting system, is mounted on the robot tip. An autostereoscopic screen is adopted to display the surgical scenario as an alternative to 3-D helmets or polarizing glasses. A rough position of the stereocamera can be determined along the abdominal wall by dragging the robot with a set of external permanent magnets (EPMs). Once the camera is set in the desired position, the EPMs provide fixation, while the internal mechanism allows fine tilt adjustment. Considering the deformable round shape of the insufflated abdomen wall and in order to replicate the precise roll motion usually provided by the endoscopist's hands, this prototype embeds an actuated mechanism that adjusts the stereocamera horizon and thus prevents any visual discomfort. Finally, the platform was preliminarily tested in vivo in a LESS scenario, demonstrating its advantages for eliminating potential conflicts with the operative tools and enabling the introduction of an additional instrument through the same access port used for stereoscopic vision.