Robotic steering of flexible endoscopes

Flexible endoscopes were originally designed for non-invasive inspection of body cavities and hollow organs. Today, they are also used for complex minimal invasive interventions. Control of the endoscope is difficult and complexity rises with interventional procedures. Endoscopists suffer from long learning curves, ergonomic complaints and multi-person control is needed to steer endoscope and instrument(s). Robotics have the potential to overcome these problems. The combined forces of a technical university, mechatronic company and physicians from multiple hospitals led to the design of an add-on robotic platform. The platform aims to improve usability of conventional flexible endoscopes for complex interventions. These interventions require accurate and precise tip steering. This thesis describes the design and clinical evaluation of the platform's tip steering module. An optimal user interface and control algorithm was sought to improve usability of the endoscope in clinical practise. The results showed non-inferiority of the platform in simulated diagnostic procedures. A patient study showed that the add-on platform allows a safe and feasible introduction of an endoscope through the bowel. The robotic platform proposed in this thesis is based on pairing with conventional endoscopes. Consequently, performance results of the add-on platform also depend on the tip bending response of the used endoscopes. An evaluation of the tip bending response of clinically used endoscopes suggests that the vast majority of endoscopes are not optimally tuned to reach maximal bending angles and adequate tip response. Innovations that close the control loop and hysteresis control methods are expected to further improve precise and efficient endoscope tip steering.