A Concentric Tube Robot System for Rigid Bronchoscopy: A Feasibility Study on Central Airway Obstruction Removal


New robotic systems have recently emerged to assist with peripheral lung access, but a robotic system for rigid bronchoscopy has yet to be developed. We describe a new robotic system that can deliver thin robotic manipulators through the ports of standard rigid bronchoscopes. The manipulators bend and elongate to provide maneuverability of surgical tools at the endoscope tip, without endoscope motion. We describe an initial feasibility study on the use of this system to bronchoscopically treat a central airway obstruction (CAO). CAO is prevalent and can be life-threatening in patients with large tumors, and conventional rigid bronchoscopic treatments place patients at risk of complications including broken teeth, neck trauma and damage to oropharyngeal structures due to significant forces induced by bronchoscope tilting and manipulation. In this study, we used an ex vivo ovine airway model to demonstrate the ability of a physician using the robotic system to efficiently remove tissue and restore the airway. Pre- and post-operative CT scans showed that the robot was able to reduce the degree of airway obstruction stenosis from 75 to 14% on average for five CAO resections performed in an ex vivo animal model. Using cadaver experiments, we demonstrated the potential of the robotic system to substantially reduce the intraoperative forces applied to the patient’s head and neck (from 80.6 to 4.1 N). These preliminary results illustrate that CAO removal is feasible with our new rigid bronchoscopy robot system, and that this approach has the potential to reduce forces applied to the patient due to bronchoscope angulation, and thereby reduce the risk of complications encountered during CAO surgery.

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The authors thank the National Institutes of Health (NIH) Small Business Technology Transfer (STTR) for Grant R41 HL140709 which supported the work described in this paper. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Institutes of Health.

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Correspondence to Joshua B. Gafford.

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Conflict of interest

The authors have reported to Annals of Biomedical Engineering the following conflicts of interest: The robot concept described in this paper originated in R.W.’s laboratory at Vanderbilt University, and is in the early stages of technology transfer to a startup company, Virtuoso Surgical, Inc., created for purposes of bringing this technology to market, under a Phase I STTR grant from the National Institutes of Health. S.W., N.D., E.B., R.H., D.H. and R.W. are equity holders in Virtuoso. S.W., N.D., E.B. and R.H. are employed by Virtuoso. R.W. and R.H. are founders and board members of Virtuoso, with R.W. serving as president and R.H. serving as Chief Operating Officer. The robot described in this paper is an early-stage prototype, and has not yet begun to go through the FDA approval process. It is not cleared for human use or available for purchase. It will undergo a number of extensive design revisions before becoming a commercial product.

Ethical Approval

All experiments were performed by a single interventional pulmonologist (F.M.). We did not recruit a multiple-user cohort for these proof-of-concept experiments. Based on this consideration, and the fact that no patients or live animals were involved in our experiments, prior approval from an ethics committee (IRB or IACUC) was not required.

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Gafford, J.B., Webster, S., Dillon, N. et al. A Concentric Tube Robot System for Rigid Bronchoscopy: A Feasibility Study on Central Airway Obstruction Removal. Ann Biomed Eng 48, 181–191 (2020). https://doi.org/10.1007/s10439-019-02325-x

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  • Central Airway Obstruction
  • Bronchoscopy
  • Robotics