Taxonomy of instructions given to residents in laparoscopic cholecystectomy

Comparison of Kinect and Leap Motion for Intraoperative Image Interaction

Background. Touchless interaction devices have increasingly garnered attention for intraoperative imaging interaction, but there are limited recommendations on which touchless interaction mechanisms should be implemented in the operating room. The objective of this study was to evaluate the efficiency, accuracy, and satisfaction of 2 current touchless interaction mechanisms-hand motion and body motion for intraoperative image interaction. Methods. We used the TedCas plugin for ClearCanvas DICOM viewer to display and manipulate CT images. Ten surgeons performed 5 image interaction tasks-step-through, pan, zoom, circle measure, and line measure-on the 3 input interaction devices-the Microsoft Kinect, the Leap Motion, and a mouse. Results. The Kinect shared similar accuracy with the Leap Motion for most of the tasks. But it had an increased error rate in the step-through task. The Leap Motion led to shorter task completion time than the Kinect and was preferred by the surgeons, especially for the measure tasks. Discussion. Our study suggests that hand tracking devices, such as the Leap Motion, should be used for intraoperative imagining manipulation tasks that require high precision.

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.