Ergonomically enhanced flexible endoscopy control system: prototype construction and phantom testing

Patrick Cheng, MS, Emmanuel Wilson, MS, Kelly Swords, MD, MPH, Kyle Wu, MD, MBA, Kevin Cleary, PhD, Craig A Peters, MD

Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National

Flexible endoscopy has been a widely used technology for 50 years, but the user interface has changed little and remains an ergonomic challenge. To facilitate more efficient and safer use of flexible endoscopes, we developed a novel electromechanical control system and user interface for flexible endoscopes suitable for commercially available instruments of various sizes.

The electromechanical device includes a mechanical cradle that securely holds the endoscope body and motorizes the three degrees of freedom of the endoscope: translation of the body, rotation of the body, and flexion of the tip. The motors are connected to a Galil motion control board, which provides precision control of each degree of freedom. The motion control board is connected to a personal computer through an Ethernet cable. The user input is through a Razer Hydra gaming controller, which is connected to the computer via the USB port. Custom C++ software was written to interface the controller with the motion control system.

Visual field zone mapping was used to translate the operator’s movements to movements of the ureteroscope. A ureteroscopy phantom was used to define the optimal mapping based on user testing. Pre-clinical use validation was performed in the phantom and tested by 6 urologists with varying levels of flexible ureteroscope experience. The task was to identify and contact four preplaced objects in known segments of the kidney without radiographic control. Operators rated various elements of the user interface based on a 0 (least) to 5 (best) scale.

Mean time to completion was related to experience level. Users reported generally favorable impressions, specifically: ease of use=3.7; fluidity=3.0; flexion control=3.3; intuitive motion=3.7; comfort 4.0; avoidance of trauma=2.0.

Further development will include defining more robust testing parameters, expert user assessment, clinical validation and development of adaptor devices to permit using this system for various endoscopic applications.

This novel control system for flexible endoscopy offers several important advantages including wide applicability to endoscope size and type, the ability to use commercially available endoscopes without redesign, the ergonomically advantageous user interface that can potentially reduce procedure time, tissue trauma, and instrument damage.


Session: Poster Presentation

Program Number: P669

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