A dual-bending endoscope with shape-lockable hydraulic actuation and water-jet propulsion for gastrointestinal tract screening.

Abstract

Traditional flexible endoscopes are sophisticated medical devices that require frequent and expensive maintenance. Therefore, their implementation within low-income and rural regions is challenging due to their high cost, complex sterilization process and poor portability. This paper aims to develop an endoscopic platform that is low-cost, disposable and portable, with the primary goal of reducing gastric cancer-related mortality among low- and middle-income communities through wider access to regular screening programs. The endoscope employs a custom microvalve to switch between hydraulic actuation of a spatial bending fluidic actuator and water-jet actuation. Three alloy wires with buckle attachments are connected to a pneumatic balloon which facilitates reversible shape-locking of the actuator, and thus supports stable scanning by water-jet actuation. Distal tip of the device has an internal charge-coupled device camera for inspection. Experiments demonstrated a 58% increase in the workspace after introduction of the water-jet and more than three times the load-locking ability variation. Phantom experiment was also conducted for performance comparison with a traditional endoscope. By controlling the pressure of supplied water and the inflation of locking balloon, the endoscope achieves a satisfactory workspace and a remarkable shape-locking ability, demonstrating its potential clinical value in improving the prospects for upper gastrointestinal tract disease screening, especially gastric cancer.