The BlueDRAGON - a system for measuring the kinematics and dynamics of minimally invasive surgical tools in-vivo

Minimally invasive surgery involves a multidimensional series of tasks requiring a synthesis between visual information and the kinematics and dynamics of the surgical tools. Analysis of these sources of information is a key step in mastering MIS, but may also be used to define objective criteria for characterizing surgical performance. The BlueDRAGON is a new system for acquiring the kinematics and dynamics of two endoscopic tools synchronized with the visual view of the surgical scene. It includes two four-bar passive mechanisms equipped with position and force torque sensors for measuring the positions and orientations of the two endoscopic tools along with the forces and torques (F/T) applied by the surgeon´s hands. The methodology of decomposing the surgical task is based on a fully connected, 28 finite-states Markov model where each states corresponded to a fundamental tool/tissue interaction based on the tool kinematics and associated with unique F/T signatures. The experimental protocol includes seven MIS tasks performed on an animal model by 30 surgeons at different levels of their residency training including expert surgeons. From the preliminary analysis of these data, the major differences between residents at different skill levels are discussed. Systems like surgical robots or virtual reality simulators that inherently measure the kinematics and dynamics of the surgical tool may benefit from inclusion of the proposed methodology for the analysis of efficacy and objective evaluation of surgical skills during training.