Optical angle and visuospatial ability affect basic laparoscopic simulator task performance.

Surgical trainees show decreased performance during laparoscopic surgery when the laparoscope (camera) is not aligned with their line of sight towards the operating area. In this study we investigate the influence of visuospatial ability on laparoscopic simulator performance under such non-zero optical angles. Novices were invited to participate in a laparoscopic training session. After completing a visuospatial ability assessment, they performed a simplified laparoscopic task on an in-house developed laparoscopic simulator under eight different optical angles ranging between 0° and 315° in steps of 45°. Data-analysis showed decreased performance under all non-zero optical angles for task duration (mean difference between 1506 and 5049 ms, standard error between 499 and 507, p < .05) and for accuracy under optical angles greater than ±45° (mean difference between 1.48 and 2.11, standard error 0.32, p < .01). Performance-zones were identified for various optical angle ranges and differed for task duration and accuracy. Participants of high visuospatial ability performed significantly better under non-zero angles for accuracy compared to participants of low visuospatial ability (mean difference 0.95, standard error 0.34, p < .01), except for the 180° optical angle (no difference).

Laparoscopic simulator performance and learning curves under different optical angles.

BACKGROUND: Deviated optical angles create visuospatial and psychomotor challenges during laparoscopic procedures, resulting in delayed operative time and possibly adverse events. If it is possible to train the skills needed to work under these deviated optical angles, this could benefit procedure time and patient safety. This study investigates the influence of the optical angle on development of basic laparoscopic surgical skills. METHODS: A total of 58 medical students performed a four-session laparoscopic training course on a Virtual Reality Simulator. During each session, they performed an identical task under optical angles of 0°, 45° and - 45°. Performance parameters of task duration and damage were compared between the optical angles to investigate the effect of optical angle on performance development. The 4th session performance was compared to the 2nd session performance for each angle to determine improvement. RESULTS: Participants performed the task significantly faster under the 0° optical angle compared to the plus and minus 45° optical angles during the last three sessions (z between - 2.95 and - 2.09, p < .05). Participants improved significantly and similarly for task duration during the training course under all optical angles. At the end of the training course however significant performance differences between the zero and plus/minus 45 optical angles remained. Performance for damage did not improve and was not affected by optical angle throughout the course. CONCLUSION: Dedicated virtual reality training improves laparoscopic basic skills performance under deviated optical angles as it leads to shorter task duration, however a lasting performance impairment compared to the 0° optical angle remained. Training for performing under deviating optical angles can potentially shorter the learning curve in the operating room.

Speed versus damage: using selective feedback to modulate laparoscopic simulator performance.

BACKGROUND: Adaptive training is an approach in which training variables change with the needs and traits of individual trainees. It has potential to mitigate the effect of personality traits such as impulsiveness on surgical performance. Selective performance feedback is one way to implement adaptive training. This paper investigates whether selective feedback can direct performance of trainees of either high- or low impulsiveness. METHODS: A total of 83 inexperienced medical students of known impulsiveness performed a four-session laparoscopic training course on a Virtual Reality Simulator. They performed two identical series of tasks every session. During one series of tasks they received performance feedback on duration and during the other series they received feedback on damage. Performance parameters (duration and damage) were compared between the two series of tasks to assess whether selective performance feedback can be used to steer emphasis in performance. To assess the effectiveness of selective feedback for people of high- or low impulsiveness, the difference in performance between the two series for both duration and damage was also assessed. RESULTS: Participants were faster when given performance feedback for speed for all exercises in all sessions (average z-value = - 4.14, all p values < .05). Also, they performed better on damage control when given performance feedback for damage in all tasks and during all sessions except for one (average z-value = - 4.19, all but one p value < .05). Impulsiveness did not impact the effectiveness of selective feedback. CONCLUSION: Selective feedback on either duration or damage can be used to improve performance for the variable that the trainee receives feedback on. Trainee impulsiveness did not modulate this effect. Selective feedback can be used to steer training focus in adaptive training systems and can mitigate the negative effects of impulsiveness on damage control.

Fast or safe? The role of impulsiveness in laparoscopic simulator performance.

BACKGROUND: Little is known about the relation between impulsiveness and surgical performance even though research in similar high-risk/high-skills shows evidence of more hazardous behavior by impulsive professionals. We investigated the impact of impulsiveness on laparoscopic simulator performance. METHODS: Eighty-three subjects participated in a four-session laparoscopic training course. Based on the Eysenck Personality test, we created equal sized high- and low impulsiveness groups and compared task duration and errors on tasks for two laparoscopic simulators. RESULTS: The low impulsiveness group outperformed the high impulsiveness group on damage on the LapSim virtual reality trainer (U = 459, p < .049), and showed a trend towards better error performance on the FLS videotrainer. We found no differences on task duration. CONCLUSIONS: In surgical simulation training, high impulsiveness is associated with creating more damage, but not with faster performance. Time needed to correct errors may have obscured faster performance in the high impulsiveness group. SUMMARY FOR THE TABLE OF CONTENTS: Subjects were divided into high- and low impulsiveness groups based on the Eysenck Impulsiveness Inventory test. Performance (time and errors) were compared between groups for tasks on the LapSim virtual reality trainer and FLS videotrainer. Low impulsive subjects outperformed high impulsive subjects on errors.

Peers versus Pros: Feedback using standards in simulation training.

BACKGROUND: Creating and updating expert performance-based standards for simulators is labor intensive and requires the regular availability of expert surgeons. We investigated how peer performance based standards compare to expert performance based standards. METHODS: One hundred medical students took part in a four-session laparoscopic basic skills simulator training course. Performance for the FLS videotrainer tasks were compared between students who received feedback based on either peer standards, expert standards or no feedback at all (control group). RESULTS: No difference in performance between our feedback groups was found. Compared to the control group, they were 18-36% faster but made 52% more errors for tasks on the FLS video trainer (U range [93.5-957], average p < .01). CONCLUSIONS: We demonstrated that feedback based on peer standards is equally effective as feedback based on expert standards. The found trade-off between speed and error is not desirable and warrants further investigation.

When experts are oceans apart: comparing expert performance values for proficiency-based laparoscopic simulator training.

BACKGROUND: Surgical training is moving away from the operating room toward simulation-based skills training facilities. This has led to the development of proficiency-based training courses in which expert performance data are used for feedback and assessment. However, few expert value data sets have been published, and no standard method for generating expert values has been adopted by the field. METHODS: To investigate the effect of different proficiency value data sets on simulator training courses, we (1) compared 2 published expert performance data sets for the LapSim laparoscopic virtual-reality simulator (by van Dongen et al. and Heinrichs et al.) and (2) assessed the effect of using either set on LapSim training data obtained from 16 local residents in surgery and gynecology. RESULTS: Across all simulator tasks, the experts consulted by van Dongen et al. performed better on motion efficiency, but not on duration or damage control. Applying both proficiency sets to training data collected during a basic skills laparoscopic simulator course, residents would have graduated on an average in 1.5 fewer sessions using the Heinrichs expert values compared with the van Dongen expert values. CONCLUSIONS: The selection of proficiency values for proficiency-based simulator training courses affects training length, skills level assessment, and training costs. Standardized, well-controlled methods are necessary to create valid and reliable expert values for use in training and research.

da Vinci skills simulator for assessing learning curve and criterion-based training of robotic basic skills.

OBJECTIVE: To answer 2 research questions: what are the learning curve patterns of novices on the da Vinci skills simulator parameters and what parameters are appropriate for criterion-based robotic training. MATERIALS AND METHODS: A total of 17 novices completed 2 simulator sessions within 3 days. Each training session consisted of a warming-up exercise, followed by 5 repetitions of the "ring and rail II" task. Expert participants (n = 3) performed a warming-up exercise and 3 repetitions of the "ring and rail II" task on 1 day. We analyzed all 9 parameters of the simulator. RESULTS: Significant learning occurred on 5 parameters: overall score, time to complete, instrument collision, instruments out of view, and critical errors within 1-10 repetitions (P <.05). Economy of motion and excessive instrument force only showed improvement within the first 5 repetitions. No significant learning on the parameter drops and master workspace range was found. Using the expert overall performance score (n = 3) as a criterion (overall score 90%), 9 of 17 novice participants met the criterion within 10 repetitions. CONCLUSION: Most parameters showed that basic robotic skills are learned relatively quickly using the da Vinci skills simulator, but that 10 repetitions were not sufficient for most novices to reach an expert level. Some parameters seemed inappropriate for expert-based criterion training because either no learning occurred or the novice performance was equal to expert performance.