Design, prototype development and pre-clinical validation of a novel instrument with a compliant steerable tip to facilitate endoscopic ear surgery

Abstract

This work presents the design of a novel compliant steerable tip (CST) instrument to facilitate transcanal (or totally) endoscopic ear surgery (TEES). The evolution of the instrument’s design is shown, where prototypes were evaluated by surgeons and their feedback was used to inform the design changes for the next prototype iteration. The final prototype enables the surgeon to articulate the compliant tip to achieve the desired bending curvature while automatically locking in place and providing dissection and suction capabilities. Pre-clinical validation testing was performed in goat and human cadaver models by two surgeons who successfully removed an allograft from the middle ear. Time and the number of blockages while suctioning saline in both cadaver models were measured and compared with current instruments used during TEES. The CST took significantly less time to suction saline within a flooded middle ear compared to the Panetti suction dissector (PSD) for atticus and underwent less blockages than the PSD for atticus, ear drum and sinus tympani instruments, Wilcoxon Method p < .05. Our study demonstrates the development and successful clinical evaluation of a minimally invasive surgical instrument designed to facilitate endoscopic approaches to the ear.

Keywords:

• Endoscopy
• device innovation
• notched tube compliant wrist
• design iteration
• user study

Acknowledgements

We thank the University of Toronto Surgical Skills Centre at Mount Sinai Hospital for facilitating the human cadaver and goat model testing. We would like to acknowledge Brandon Peel for 3D printing the models and instrument prototype components and Ashley Hui for composing the illustration in Figure 1.

Patent consent

The following patent applications have been filed.

USA Provisional Patent filed 04/16/2018, Application Number: US 62/658,088

Canada Patent filed 04/16/2018, Application Number: 3,001,593

International PCT filed 04/16/2019, Application Number: PCT/CA2019/050475

Disclosure statement

No potential conflict of interest was reported by the author(s).

Table 1. List of conferences, courses and meetings where surgeon participants gave feedback on the instrument prototypes. Number of staff, residents and fellows are listed.

Additional information

Funding

AS has received salary support & funding for her PhD Degree from the following: Director’s Innovation Award, Institute of Biomaterials and Biomedical Engineering, University of Toronto; Department of Otolaryngology – Head & Neck Surgery, Hospital for Sick Children.