Transoral Robotic Surgical Proficiency Via Real-Time Tactile Collision Awareness System

Abstract

Objectives: In 2009, the Food and Drug Administration approved the use of the surgical robotic system for removal of benign and malignant conditions of the upper aerodigestive tract. This novel application of robotic-assisted surgery, termed transoral robotic surgery (TORS), places robotic instruments and camera system through the mouth to reach recessed areas of the pharynx and larynx. Over the successive decade, there was a rapid adoption of TORS with a surgical growth rate that continues to increase. Despite the rapid clinical acceptance, the field of TORS has not yet seen substantive changes or advances in the technical shortcomings, the lack of which has restricted objective TORS-specific surgical skills assessment as well as subsequent skills improvement efforts. One of the primary technical challenges of TORS is operating in a confined space, where the robotic system is maneuvered within the restrictive boundaries of the mouth and throat. Due to these confined boundaries of the pharynx, instruments can frequently collide with anatomic structures such as teeth and bone, producing anatomic collisions. Therefore, we hypothesized that anatomic collisions negatively impact TORS surgical performance. Secondarily, we hypothesized that avoidance of unwanted anatomic collisions could improve TORS surgical proficiency.

Methods: Design and fidelity testing for a custom TORS training platform with an integrated anatomic collision-sensing system providing real-time tactile feedback is described. Following successful platform assembly and testing, validation study using the platform was carried through prospective surgical training with trial randomization. Twenty otolaryngology-head and neck surgery residents, each trainee performing three discrete mock surgical trials (n = 60), performed the initial system validation. Ten of the 20 residents were randomized to perform the surgical trials utilizing the real-time feedback system. The remaining 10 residents were randomized to perform the surgical trials without the feedback system, although the system still could record collision data. Surgical proficiency was measured by Global Evaluative Assessment of Robotic Skills (GEARS) score, time to completion, and tumor resection scores (categorical scale ranging 0-3, describing the adequacy of resection).

Results: Major anatomic collisions (greater than 5N of force) negatively affected GEARS robotic skills. A mixed model analysis demonstrated that for every additional occurrence of a major collision, GEARS robotic skills assessment score would decrease by 0.29 points (P = .04). Real-time collision awareness created significantly fewer major (> 5 N) anatomic collisions with the tactile feedback system active (n = 30, mean collisions = 2.9 ± 4.2) as compared with trials without tactile feedback (n = 30, mean collisions = 12.53 ± 23.23) (P < .001). The second assessment measure of time to completion was unaffected by the presence of collisions or by the use of tactile feedback system. The third proficiency assessment was measured with tumor resection grading. Tumor resection scores was significantly (P = .02) improved with collision awareness system activated than trials without collision awareness.

Conclusion: In order to test our primary hypothesis, a novel TORS training platform was successfully developed that provides collision force measurements including frequency, severity, and duration of anatomic collisions. Additionally, the platform was modulated to provide real-time tactile feedback of the occurrence of out-of-field collisions. Utilizing this custom platform, our hypothesis that anatomic collisions during TORS diminishes surgical performance was supported. Additionally, our secondary hypothesis that subsequent reduction of anatomic collisions improves TORS proficiency was supported by the surgical trial. Dedicated investigation to characterize the effect size and clinical impact is required in order to translate this finding into training curriculums and into clinical utilization.

Level of evidence: II (Randomized trial) Laryngoscope, 130:S1-S17, 2020.

Keywords: TORS; haptics; robotic surgery; surgical skill; training.