Presented by: Jonguk Lee MASc, BASc
St. Michael's Hospital, Department of Surgery, Division of Urology

Introduction

Hand/instrument motion-tracking in surgical simulation provides valuable data to improve psychomotor skills and can serve as a formative evaluation tool. While motion analysis has been well-studied in laparoscopic surgery, it has been poorly studied in endoscopic surgery. Very few studies look at motion-tracking for flexible ureteroscopy (fURS), a common surgical procedure which requires hand dexterity and 3D spatial awareness. To address this gap, we designed a synchronized motion-tracking and video capture system for fURS capable of collecting objective metrics for use in surgical skills training.

Materials

A single-use flexible ureteroscope was used to design and test our system. Motion tracking of the ureteroscope was performed using the Polhemus Patriot platform, inertial measurement units (IMUs) and an optical sensor. Specifically, the position (x, y, z) and orientation (roll, pitch, yaw) of the ureteroscope handle, deflection of the ureteroscope lever, and translation of the scope insertion point were collected. Video capture of the operator’s hands was collected with a Raspberry Pi camera, and the recording of the endoscopic view was collected from the video tower. All peripherals were controlled by a Raspberry Pi 4 and synchronized to its system clock.

Results

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Our system demonstrated good accuracy in detecting translation of the ureteroscope in the x- and y-axes, and yaw, pitch and roll of the ureteroscope at discrete orientations of 0, ±30, ±60 and ±90 degrees. Unique to fURS, the deflection of the lever was captured by the difference in IMU static accelerations with good accuracy. The optical sensor detected the translation of the ureteroscope at the insertion point with an average error of 5.51% when traversing distances of 25, 50 and 100 mm a total of ten times each.

Conclusion

We successfully developed a system capable of collecting motion-analysis parameters and capturing videos unique to fURS. Future studies will focus on establishing the construct validity of this tool.

Funding

We would like to thank Unity Health Toronto for funding the study through the ​​Keenan Research Summer Student (KRSS) Program.

Lead Authors

Jessica Trac, MD
Temerity Faculty of Medicine, University of Toronto

Co-Authors

Kai-Ho Fok, MD, MASc (c)
Temerty Faculty of Medicine, University of Toronto; St. Michael's Hospital, Department of Surgery, Division of Urology

Sufyan Shaikh, HBSc, MSc (c)
St. Michael's Hospital, Department of Surgery, Division of Urology; Institute of Medical Science, University of Toronto

Kashif Visram, MD, BMSc
St. Michael’s Hospital, Division of Urology, University of Toronto

Brian Carrillo, PHD
WellSpring Research

Monica Farcas, MD, MEng
Temerty Faculty of Medicine, University of Toronto; St. Michael's Hospital, Department of Surgery, Division of Urology; Li Ka Shing Knowledge Institute, St. Michael's Hospital; Department of Surgery, University of Toronto