Virtual pointer for gaze guidance in laparoscopic surgery.

BACKGROUND: A challenge of laparoscopic surgery is learning how to interpret the indirect view of the operative field. Acquiring professional vision-understanding what to see and which information to attend to, is thereby an essential part of laparoscopic training and one in which trainers exert great effort to convey. We designed a virtual pointer (VP) that enables experts to point or draw free-hand sketches over an intraoperative laparoscopic video for a novice to see. This study aimed to investigate the efficacy of the virtual pointer in guiding novices' gaze patterns. METHODS: We conducted a counter-balanced, within-subject trial to compare the novices' gaze behaviors in laparoscopic training with the virtual pointer compared to a standard training condition, i.e., verbal instruction with un-mediated gestures. In the study, seven trainees performed four simulated laparoscopic tasks guided by an experienced surgeon as the trainer. A Tobii Pro X3-120 eye-tracker was used to capture the trainees' eye movements. The measures include fixation rate, i.e., the frequency of trainees' fixations, saccade amplitude, and fixation concentration, i.e., the closeness of trainees' fixations. RESULTS: No significant difference in fixation rate or saccade amplitude was found between the virtual pointer condition and the standard condition. In the virtual pointer condition, trainees' fixations were more concentrated (p = 0.039) and longer fixations were more clustered, compared to the Standard condition (p = 0.008). CONCLUSIONS: The virtual pointer effectively improved surgical trainees' in-the-moment gaze focus during the laparoscopic training by reducing their gaze dispersion and concentrating their attention on the anatomical target. These results suggest that technologies which support gaze training should be expert-driven and intraoperative to efficiently modify novices' gaze behaviors.

Effects of a Virtual Pointer on Trainees' Cognitive Load and Communication Efficiency in Surgical Training.

We investigated the cognitive load effect of a trainer providing surgical instruction by pointing/drawing over laparoscopic video to a trainee. Results showed that while cognitive load is higher overall with the use of the instructional system, there is a decrease by the second experience of being instructed by the Virtual Pointer. Further analysis showed that trainees were more likely to perform the surgical task and watch/listen to the trainer's instruction at the same time when the instructional system was used. This is thought to be an indication of more efficient communication when using the instructional system. Thus, although there is a small cognitive overload with the instructional system initially, the more efficient communication allows trainees to better integrate the knowledge and instructions being conveyed into the actions they must perform - indicating a better learning environment.

A virtual pointer to support the adoption of professional vision in laparoscopic training.

PURPOSE: To assess a virtual pointer in supporting surgical trainees' development of professional vision in laparoscopic surgery. METHODS: We developed a virtual pointing and telestration system utilizing the Microsoft Kinect movement sensor as an overlay for any imagine system. Training with the application was compared to a standard condition, i.e., verbal instruction with un-mediated gestures, in a laparoscopic training environment. Seven trainees performed four simulated laparoscopic tasks guided by an experienced surgeon as the trainer. Trainee performance was subjectively assessed by the trainee and trainer, and objectively measured by number of errors, time to task completion, and economy of movement. RESULTS: No significant differences in errors and time to task completion were obtained between virtual pointer and standard conditions. Economy of movement in the non-dominant hand was significantly improved when using virtual pointer ([Formula: see text]). The trainers perceived a significant improvement in trainee performance in virtual pointer condition ([Formula: see text]), while the trainees perceived no difference. The trainers' perception of economy of movement was similar between the two conditions in the initial three runs and became significantly improved in virtual pointer condition in the fourth run ([Formula: see text]). CONCLUSIONS: Results show that the virtual pointer system improves the trainer's perception of trainee's performance and this is reflected in the objective performance measures in the third and fourth training runs. The benefit of a virtual pointing and telestration system may be perceived by the trainers early on in training, but this is not evident in objective trainee performance until further mastery has been attained. In addition, the performance improvement of economy of motion specifically shows that the virtual pointer improves the adoption of professional vision- improved ability to see and use laparoscopic video results in more direct instrument movement.