Construct validity of eoSim - a low-cost and portable laparoscopic simulator.

Purpose: To examine the construct validity of the low-cost, portable laparoscopic simulator eoSim using motion analysis.Material and methods: Novice and experienced surgeons (≤ 100 and >100 laparoscopic procedures performed, respectively) completed four tasks on the eoSim using the SurgTrac software: intracorporeal suture and tie, tube ligation, peg capping and precision cutting. The following metrics were recorded: Time to complete task, distance traveled, handedness (left- versus right hand use), time off-screen, distance between instrument tips, speed, acceleration and motion smoothness.Results: Compared to novices (n = 22), experienced surgeons (n = 14) completed tasks in less time (p ≤ .025), except when performing peg capping (p = .052). On all tasks, they also scored lower on the distance metric (p ≤ .001). Differences in handedness (left hand compared between groups, right hand compared between groups) were found to be significant for three tasks (p ≤ .025). In general, the experienced group made greater use of their left hand than the novice group.Conclusion: The eoSim can differentiate between experienced and novice surgeons on the tasks intracorporeal suture and tie, tube ligation and precision cutting, thus providing a convenient method for surgical departments to implement testing of their surgeons' basic laparoscopic skills.

Optimal timing of assessment tasks depending on experience level of surgical trainees.

Introduction: Box trainers with motion analysis are important add-ons to surgical training and skills assessment outside the operating room, given that they exhibit construct validity.Material and methods: Four different tasks were tested for construct validity on a new laparoscopic box trainer with integrated motion analysis. Tracking data from the simulator were analyzed for eighteen parameters per task using an in-house software comparing participants with three different experience levels.Results: In total, ten novices, 22 intermediates and 16 experts enrolled. No or limited significant differences were found for the peg picker and rope race. For the precision cutting task 12 parameters showed significant difference between novices and intermediates, 14 between novices and experts and one between intermediates and experts. For the suture task the corresponding results were one, 15 and six.Conclusions: The precision cutting and suture task both showed construct validity for many of the parameters. While the precision cutting task distinguished best between novices and the other two groups, the suture task distinguished best between experts and the other two groups. These results show the importance of the timing of an assessment task, and that an assessment task might have limited value if experience levels are not considered.

Psychomotor skills assessment by motion analysis in minimally invasive surgery on an animal organ.

BACKGROUND: A high level of psychomotor skills is required to perform minimally invasive surgery (MIS) safely. To be able to measure these skills is important in the assessment of surgeons, as it enables constructive feedback during training. The aim of this study was to test the validity of an objective and automatic assessment method using motion analysis during a laparoscopic procedure on an animal organ. MATERIAL AND METHODS: Experienced surgeons in laparoscopy (experts) and medical students (novices) performed a cholecystectomy on a porcine liver box model. The motions of the surgical tools were acquired and analyzed by 11 different motion-related metrics, i.e., a total of 19 metrics as eight of them were measured separately for each hand. We identified for which of the metrics the experts outperformed the novices. RESULTS: In total, two experts and 28 novices were included. The experts achieved significantly better results for 13 of the 19 instrument motion metrics. CONCLUSIONS: Expert performance is characterized by a low time to complete the cholecystectomy, high bimanual dexterity (instrument coordination), a limited amount of movement and low measurement of motion smoothness of the dissection instrument, and relatively high usage of the grasper to optimize tissue positioning for dissection.