Integration of a Flexible Endoscope into a Robotic Arm Setup for Solo-Surgery in Ureteroscopy

Kurzfassung

Background. Ureteroscopy is a treatment option for urinary stones, which can occlude the passage of urine, causing pain and inflammation. It describes a surgical technique using a flexible endoscope to enter ureter and kidney via the urethral orifice. This complex procedure requires two surgeons to operate in a limited space causing non-ergonomic postures and communication problems. The DLR robot-assisted approach aims to introduce solo-surgery to ureteroscopy, allowing full control to one surgeon and improved ergonomics. Present thesis contributes by optimizing the integration of surgical features to an endoscope fixed to a light-weight versatile robotic arm (DLR MIRO, Germany). Methods. The optimization methodically follows the guidelines VDI 2221 and 2206. Additionally, DIN EN ISO 9241-11 and 9241-210 norms are used to consider ergonomics and usability for human-system interface design. Components are developed using rapid prototyping means, particularly 3D printing. For functional and usability testing, a simulator test conducted by a urologist and a user test with non-medical participants are set up. Optimal robotic arm position in the operating room (OR) is determined by a mock-up test. Besides video analysis, subjective assessments of the system are collected using the NASA Task Load Index (NASA-TLX) and the System Usability Scale (SUS). Results. A developed shell around the endoscope handle creates interfaces to surgical features to integrate them to the robotic arm. These are touch sensors for robotic arm mode control, buttons to manipulate irrigation, a mechanism for accessory instrument positioning and direct stone basket handling. Tests prove functional reliability of developed features, and a comparable SUS (previous: 71.3 ± 17.6 vs. new: 73 ± 13.4) and NASA-TLX score (previous: 42.7 ± 15.8 vs. new: 54.9 ± 12.4) to the previous version of the setup. Surgeons' feedback and testing suggest a robot cart with integrated external systems positioned lateral to the patient with the robotic arm crossing above the patient leg to reach the surgeon as space-saving and ergonomics improving solo-surgery setup integration into the OR. Conclusion. This work supports the feasibility of solo-surgery in ureteroscopy. Distributing tasks between one surgeon and the optimized robotic arm setup improves control, space and ergonomics. However, ergonomic challenges remain, requiring further optimization to improve efficiency and satisfaction. At last, improving surgeon's support during complete procedure requires additional functions implementation.