A novel gaze-controlled flexible robotized endoscope; preliminary trial and report

Abstract

Background: Interventional endoluminal therapy is rapidly advancing as a minimally invasive surgical technique. The expanding remit of endoscopic therapy necessitates precision control. Eye tracking is an emerging technology which allows intuitive control of devices. This was a feasibility study to establish if a novel eye gaze-controlled endoscopic system could be used to intuitively control an endoscope.

Methods: An eye gaze-control system consisting of eye tracking glasses, specialist cameras and a joystick was used to control a robotically driven endoscope allowing steering, advancement, withdrawal and retroflexion. Eight experienced and eight non-endoscopists used both the eye gaze system and a conventional endoscope to identify ten targets in two simulated environments: a sphere and an upper gastrointestinal (UGI) model. Completion of tasks was timed. Subjective feedback was collected from each participant on task load (NASA Task Load Index) and acceptance of technology (Van der Laan scale).

Results: When using gaze-control endoscopy, non-endoscopists were significantly quicker when using gaze-control rather than conventional endoscopy (sphere task 3:54 ± 1:17 vs. 9:05 ± 5:40 min, p = 0.012, and UGI model task 1:59 ± 0:24 vs 3:45 ± 0:53 min, p < .001). Non-endoscopists reported significantly higher NASA-TLX workload total scores using conventional endoscopy versus gaze-control (80.6 ± 11.3 vs 22.5 ± 13.8, p < .001). Endoscopists reported significantly higher total NASA-TLX workload scores using gaze control versus conventional endoscopy (54.2 ± 16 vs 26.9 ± 15.3, p = 0.012). All subjects reported that the gaze-control had positive 'usefulness' and 'satisfaction' score of 0.56 ± 0.83 and 1.43 ± 0.51 respectively.

Conclusions: The novel eye gaze-control system was significantly quicker to use and subjectively lower in workload when used by non-endoscopists. Further work is needed to see if this would translate into a shallower learning curve to proficiency versus conventional endoscopy. The eye gaze-control system appears feasible as an intuitive endoscope control system. Hybrid gaze and hand control may prove a beneficial technology to evolving endoscopic platforms.

Keywords: Eye tracking; Robotic endoscopy; Touchless interactions.

Fig. 1

The fully robotised system

Fig. 2

The eye gaze platform in use [20]

Fig. 3

The graphical user interface of the system. Top: the view while the system is paused. Joystick control options can be seen beside the endoscopic view. Middle: The view during insertion, including graphical indicator, and Bottom: the view during withdrawal

Fig. 4

The benchtop experimental environment [20]

Fig. 5

Comparison of the two modalities (gaze—hand control) for endoscopists and non-endoscopists on both setups (Spherical cavity task (SPHt), Upper Gastrointestinal tract task (UGIt)) in terms of overall task completion time (in minutes:seconds) and NASA TLX score

Fig. 6

Performance comparison of the two modalities (gaze—hand control) for endoscopists and non-endoscopists on both setups (Spherical cavity task (SPHt), Upper Gastrointestinal tract task (UGIt)) in terms of overall task completion time

Fig. 7

A Overall NASA-TLX score and analytical results (MD, PD, TD, OP, EF, FR) for B endoscopists and non-endoscopists. NASA-TLX values range between 0 and 100, with higher values indicating higher task load. MD: mental demand, PD: physical demand TD: temporal demand, OP—own performance, EF—, FR—frustration, HC: hand control, GC: gaze-contingent control

Fig. 8

A Overall Van der Laan’s technology acceptance score by endoscopists and non-endoscopists and B analytical results. The usefulness scale derives from the average of useful/useless, good/bad, effective/superfluous, assisting/worthless, raising alertness/sleep-inducing metrics and satisfaction scale derives from pleasant/unpleasant, nice/annoying, likeable/irritating, desirable/undesirable metrics. The scale range between − 2 and + 2, with higher values indicating positive bias

Fig. 9

Likert scale results of ergonomics assessment for A endoscopists and B non-endoscopists

Fig. 10

NASA-TLX [15]

Fig. 11

Van der Laan technology acceptance scale [18]