Construct, content and face validity of the eoSim laparoscopic simulator on advanced suturing tasks

Optimizing skill acquisition: the role of self-assessment during a continuous training program for laparoscopic suturing

BACKGROUND

Mastering laparoscopic suturing, a critical aspect of minimally invasive surgery, remains a challenge. Self-assessment and 'reflection before practice' may enhance the learning curve of laparoscopic suturing. This study investigates the optimal frequency of self-assessment and reflection before practice in laparoscopic suturing training.

METHODS

Participants (medical students, surgical residents, and medical PhD students) underwent laparoscopic suturing training at home using a laparoscopic simulator (LaparoscopyBoxx). Three groups were formed: a 'control group' without self-assessment, a 'periodic self-assessment group', and a 'continuous self-assessment group'. The validated Laparoscopic Suturing Competency Assessment Tool (LS-CAT) served as self-assessment form. Participant's performance was quantified by objective parameters (time, distance, handedness, off-screen time, speed, acceleration, smoothness and distance between the instruments) measured by SurgTrac software.

RESULTS

No significant differences were observed between groups for primary outcome parameters time and distance across tests. However, significant differences emerged in secondary outcome parameters off-screen (baseline-test, p = 0.018), acceleration (baseline-test, p = 0.007), smoothness (baseline-test, p = 0.004; after-test, p = 0.038) and speed (after-test, p = 0.033) at various tests, favoring the self-assessment groups.

CONCLUSION

Self-assessment and reflection before practice may lead to more efficient instrument utilization and increased safety. A lower frequency of self-assessment and reflection before practice offered comparable benefits, which optimizes training efficiency, and is therefore recommended.

Development of anatomically accurate digital organ models for surgical simulation and training

Advancements in robotics and other technological innovations have accelerated the development of surgical procedures, increasing the demand for training environments that accurately replicate human anatomy. This study developed a system that utilizes the AutoSegmentator extension of 3D Slicer, based on nnU-Net, a state-of-the-art deep learning framework for automatic organ extraction, to import automatically extracted organ surface data into CAD software along with original DICOM-derived images. This system allows medical experts to manually refine the automatically extracted data, making it more accurate and closer to the ideal dataset. First, Python programming is used to automatically generate and save JPEG-format image data from DICOM data for display in Blender. Next, DICOM data imported into 3D Slicer is processed by AutoSegmentator to extract surface data of 104 organs in bulk, which is then exported in STL format. In Blender, a custom-developed Python script aligns the image data and organ surface data within the same 3D space, ensuring accurate spatial coordinates. By using Blender's CAD functionality within this space, the automatically extracted organ boundaries can be manually adjusted based on the image data, resulting in more precise organ surface data. Additionally, organs and blood vessels that cannot be automatically extracted can be newly created and added by referencing the image data. Through this process, a comprehensive anatomical dataset encompassing all required organs and blood vessels can be constructed. The dataset created with this system is easily customizable and can be applied to various surgical simulations, including 3D-printed simulators, hybrid simulators that incorporate animal organs, and surgical simulators utilizing augmented reality (AR). Furthermore, this system is built entirely using open-source, free software, providing high reproducibility, flexibility, and accessibility. By using this system, medical professionals can actively participate in the design and data processing of surgical simulation systems, leading to shorter development times and reduced costs.

Development and validation of the thyroidectomy training box: cervical simulator for training endoscopic transoral thyroidectomy

PURPOSE

To develop and validate a trans oral endoscopic thyroidectomy vestibular approach (TOETVA) simulator.

METHODS

The first phase of the project consisted of designing and developing a transoral thyroid surgery simulator based on real surgeries. The product has the oral cavity for attaching the three trocars and the cervical part containing the thyroid and adjacent structures. In the second phase, the simulator was validated by specialists who performed an endoscopic thyroidectomy procedure. They all filled a questionnaire about the simulator and the simulation based on the Likert scale.

RESULTS

The simulator consists of a console similar to a human bust and a high-resolution camera system connected to a 22-inch monitor. The simulator had excellent results in the visual evaluation (face validity), with 100% of responses between good and excellent for the following characteristics: synthetic structures, design, visibility of the surgery field, resistance, resilience, fulcrum effect, ergonomics, surgical material, and practicality. The last three were rated higher, with more votes for excellent. For content validity, the items that received the best ratings were, precisely, the steps relating to the surgical procedure: opening the intermuscular midline, isthmotomy, and thyroidectomy.

CONCLUSIONS

The thyroidectomy training box showed great ability to simulate a TOETVA, with satisfactory evaluations concerning its visual and content validation.

Haptic based fundamentals of laparoscopic surgery simulation for training with objective assessments

Force is crucial for learning psychomotor skills in laparoscopic tissue manipulation. Fundamental laparoscopic surgery (FLS), on the other hand, only measures time and position accuracy. FLS is a commonly used training program for basic laparoscopic training through part tasks. The FLS is employed in most of the laparoscopic training systems, including box trainers and virtual reality (VR) simulators. However, many laparoscopic VR simulators lack force feedback and measure tissue damage solely through visual feedback based on virtual collisions. Few VR simulators that provide force feedback have subjective force metrics. To provide an objective force assessment for haptic skills training in the VR simulators, we extend the FLS part tasks to haptic-based FLS (HFLS), focusing on controlled force exertion. We interface the simulated HFLS part tasks with a customized bi-manual haptic simulator that offers five degrees of freedom (DOF) for force feedback. The proposed tasks are evaluated through face and content validity among laparoscopic surgeons of varying experience levels. The results show that trainees perform better in HFLS tasks. The average Likert score observed for face and content validity is greater than 4.6 ± 0.3 and 4 ± 0.5 for all the part tasks, which indicates the acceptance of the simulator among subjects for its appearance and functionality. Face and content validations show the need to improve haptic realism, which is also observed in existing simulators. To enhance the accuracy of force rendering, we incorporated a laparoscopic tool force model into the simulation. We study the effectiveness of the model through a psychophysical study that measures just noticeable difference (JND) for the laparoscopic gripping task. The study reveals an insignificant decrease in gripping-force JND. A simple linear model could be sufficient for gripper force feedback, and a non-linear LapTool force model does not affect the force perception for the force range of 0.5-2.5 N. Further study is required to understand the usability of the force model in laparoscopic training at a higher force range. Additionally, the construct validity of HFLS will confirm the applicability of the developed simulator to train surgeons with different levels of experience.

Evaluation of a novel home-based laparoscopic and core surgical skills programme (Monash Online Surgical Training)

INTRODUCTION

Limitations to surgical education access were exacerbated during the COVID-19 Pandemic. In response, we created a national home-based comprehensive surgical skills course: Monash Online Surgical Training (MOST). Our aim was to evaluate the educational impact of this approach.

METHODS

A remote, 6-week course was designed with learning objectives aligned to the national surgical training. Participants received a personal laparoscopic bench trainer, instrument tracking software, live webinars, access to an online theoretical learning platform, and individualised feedback by system-generated or expert surgeons' assessments. Mixed method analysis of instrument tracking metrics, pre- and post-course questionnaires (11 core surgical domains) and participant comments was utilised. Data were analysed using the Mann-Whitney U test, and a p-value of < 0.05 was considered statistically significant.

RESULTS

A total of 54 participants with varied levels of experience (1 to > 6 years post-graduate level) completed MOST. All 11 learning-outcome domains demonstrated statistically significant improvement including core laparoscopic skills (1.4/5 vs 2.8/5, p < 0.0001) and handling laparoscopic instruments (1.5/5 vs 2.8/5, p < 0.0001). A total of 3460 tasks were completed reflecting 158.2 h (9492 min) of practice, 394 were submitted for formal feedback. Participants rated the course (mean 8.5/10, SD 1.6), live webinars (mean 8.9/10, SD 1.6) and instrument tracking software (mean 8.6, SD 1.7) highly. Qualitative analysis revealed a paradigm shift including the benefits of a safe learning environment and self-paced, self-directed learning.

CONCLUSION

The MOST course demonstrates the successful implementation of a fully remote laparoscopic simulation course which participants found to be an effective tool to acquire core surgical skills.

Experts in Minimally Invasive Surgery are Outperformed by Trained Novices on Suturing Skills

INTRODUCTION

Learning minimally invasive suturing can be challenging, creating a barrier to further implementation, especially with the development of easier methods. Nevertheless, mastering intracorporeal knot tying is crucial when alternative techniques prove inadequate. Therefore, the minimally invasive surgery (MIS) suturing skills of MIS experts are compared with a group of novices during their learning curve on a simulator.

METHODS

The novice participants repeatedly performed the intracorporeal suturing task on the EoSim MIS simulator (up to a maximum of 20 repetitions). The experts (>50 MIS procedures and advanced MIS experience) completed the same task once. The first and last exercises of the novices and the expert tasks were all blindly recorded and assessed by two independent assessors using the Laparoscopic Suturing Competency Assessment Tool (LS-CAT). Additionally, objective assessment parameters, "time" and "distance", using instrument tracking, were collected. The scores of the experts were then compared with the novices.

RESULTS

At the end of the training, novices significantly outperformed the experts on both the expert assessment (LS-CAT: 16.8 versus 26.8, P = 0.001) and objective parameters (median time: 190 s versus 161 s, P < 0.001; median distance: 6.1 m versus 3.6 m, P < 0.001). Although the experts showed slightly better performance than the novices during their first task, the difference was not significant on the expert assessment (LS-CAT experts 16.8, novices 20.5, P = 0.057).

CONCLUSIONS

Our findings underscore the significance of continued MIS suturing training for both residents and surgeons. In this study, trained novices demonstrated a significant outperformance of experts on both quantitative and qualitative outcome parameters within a simulated setting.

Transferability of the robot assisted and laparoscopic suturing learning curves

Robot assisted surgery (RAS) is increasingly used, and besides conventional minimally invasive surgery (cMIS) surgeons are challenged to learn an increased array of skills. This study aimed to assess the influence of both learning curves on each other. A prospective randomized crossover study was performed. Participants without cMIS or RAS experience (Groups 1 and 2), and cMIS experienced, (Group 3) were recruited. Three suturing tasks (intracorporal suturing, tilted plane and anastomosis needle transfer) were performed on the EoSim cMIS simulator or RobotiX RAS simulator up to twenty repetitions. Subsequently, Groups 1 and 2 performed the tasks on the other modality. Outcomes were simulator parameters, validated composite and pass/fail scores. In total forty-three participants were recruited. Overall RAS suturing was better in Group 1 (cMIS followed by RAS tasks) and 3 (RAS tasks) versus Group 2 (RAS followed by cMIS tasks) for time (163 s and 157 s versus 193 s p = 0.004, p = 0.001) and composite scores (92/100 and 91/100 versus 89/100 p = 0.008, p = 0.020). The cMIS suturing was better for Group 2 versus 1 (time 287 s versus 349 s p = 0.005, composite score 96/100 versus 94/100 p = 0.002). Significant differences from the RAS suturing pass/fail were reached earlier by Group 3, followed by Groups 1 and 2 (repetition six, nine and twelve). In cMIS suturing Group 2 reached significant differences from the pass/fail earlier than Group 1 (repetition four versus six). Transferability of skills was shown for cMIS and RAS, indicating that suturing experience on cMIS or RAS is beneficial in learning either approach.

Objective assessment for open surgical suturing training by finger tracking can discriminate novices from experts

It is difficult, time consuming and expensive to assess manual skills in open surgery. The aim of this study is to investigate the construct validity of a low-cost, easily accessible tracking technique for basic open suturing tasks. Medical master students, surgical residents, and surgeons at the Radboud University Medical Center were recruited between September 2020 until September 2021. The participants were divided, according to experience, in a novice group (≤10 sutures performed) and an expert group (>50 sutures performed). For objective tracking, a tablet with SurgTrac software was used, which tracked a blue and a red tag placed on respectively their left and right index finger. The participants executed four basic tasks on a suturing model: 1) knot tying by hand, 2) transcutaneous suturing with an instrument knot, 3) 'Donati' (vertical mattress suture) with an instrument knot and 4) continuous intracutaneous suturing without a knot. In total 76 participants were included: 57 novices and 19 experts. All four tasks showed significant differences between the novice group and expert group for the parameters time (p<0.001), distance (p<0.001 for Task 1, 2 and 3 and p=0.034 for Task 4) and smoothness (p<0.001). Additionally, Task 3 showed a significant difference for the parameter handedness (p=0.006) and Task 4 for speed (p=0.033). Tracking index finger movements using SurgTrac software on a tablet while executing basic open suturing skills on a simulator shows excellent construct validity for time, distance and motion smoothness in all four suturing tasks.

Assessment of Minimally Invasive Suturing Skills: Is Instrument Tracking an Accurate Prediction?

Introduction: Minimally invasive surgery (MIS) suturing demands advanced surgical skills. Therefore, it is important these skills are adequately trained and assessed. Assessment and feedback can consist of judgments and scores of expert observers or objective parameters using instrument tracking. The aim of this study was to determine to what extent objective parameters correspond to expert assessment. Methods: Participants performed an intracorporeal suturing task on the EoSim simulator repeatedly (maximum 20 repetitions) during training. The best discriminating parameters, which previously shown construct validation, were combined into a composite score, using regression analysis. All videos were blinded and assessed by 2 independent reviewers using the validated laparoscopic suturing competency assessment tool (LS-CAT). These scores were compared with the composite score. Results: A 100 videos of 16 trainees, during separate points on their learning curve, and 8 experts were used. The parameters "time" and "distance" were statistically significantly correlated with all LS-CAT domains. The composite score (calculated from "time" and "distance") showed improvement between the first and the last knot (57% versus 94%, P < .001). Also the LS-CAT score improved (28 versus 17, P < .001). However, the correlation of the composite score with the LS-CAT score was weak (R: 0.351), with an accuracy of 55/100 when pooling the outcomes based on inadequate, adequate, or good performance. Conclusion: Instrument tracking parameters (using Surgtrac) could give an indication of the skill level, however, it missed important elements, essential for reliable assessment. Therefore, expert assessment remains superior to determine the skill level in MIS suturing skills.

Comparing Simulator Metrics and Rater Assessment of Laparoscopic Suturing Skills

BACKGROUND

Laparoscopic intracorporeal suturing is important to master and competence should be ensured using an optimal method in a simulated environment before proceeding to real operations. The objectives of this study were to gather validity evidence for two tools for assessing laparoscopic intracorporeal knot tying and compare the rater-based assessment of laparoscopic intracorporeal suturing with the assessment based on simulator metrics.

METHODS

Twenty-eight novices and 19 experienced surgeons performed four laparoscopic sutures on a Simball Box simulator twice. Two surgeons used the Intracorporeal Suturing Assessment Tool (ISAT) for blinded video rating.

RESULTS

Composite Simulator Score (CSS) had higher test-retest reliability than the ISAT. The correlation between the number performed procedures including suturing and ISAT score was 0.51, p<0.001, and 0.59 p<0.001 for CSS. We found an inter-rater reliability (0.72, p<0.001 for test 1 and 0.53 p<0.001 for test 2). The pass/fail rates for ISAT and CSS were similar.

CONCLUSION

CSS and ISAT provide similar results for assessing laparoscopic suturing but assess different aspects of performance. Using simulator metrics and raters' assessments in combination should be considered for a more comprehensive evaluation of laparoscopic knot-tying competency.

The feasibility and benefit of unsupervised at-home training of minimally invasive surgical skills

BACKGROUND

Simulation-based training may be used to acquire MIS skills. While mostly done in a simulation center, it is proposed that this training can be undertaken at-home as well. The aim of this study is to evaluate whether unsupervised at-home training and assessment of MIS skills is feasible and results in increased MIS skills.

METHODS

Medical doctors and senior medical students were tested on their innate abilities by performing a pre-test on a take-home simulator. Henceforth, they followed a two-week interval training practicing two advanced MIS skills (an interrupted suture with knot tying task and a precise peg transfer task) and subsequently performed a post-test. Both tests and all training moments were performed at home. Performance was measured using motion analysis software (SurgTrac) and by expert-assessment and self-assessment using a competency assessment tool for MIS suturing (LS-CAT).

RESULTS

A total of 38 participants enrolled in the study. Participants improved significantly between the pre-test and the post-test for both tasks. They were faster (632 s vs. 213 s, p < 0.001) and more efficient (distance of instrument tips: 9.8 m vs. 3.4 m, p = 0.001) in the suturing task. Total LS-CAT scores, rated by an expert, improved significantly with a decrease from 36 at the pre-test to 20 at the post-test (p < 0.001) and showed a strong correlation with self-assessment scores (R 0.771, p < 0.001). The precise peg transfer task was completed faster (300 s vs. 163 s, p < 0.001) and more efficient as well (14.8 m vs. 5.7 m, p = 0.005). Additionally, they placed more rings correctly (7 vs. 12, p = 0.010).

CONCLUSION

Unsupervised at-home training and assessment of MIS skills is feasible and resulted in an evident increase in skills. Especially in times of less exposure in the clinical setting and less education on training locations this can aid in improving MIS skills.

Simulation-based education in urology - an update

Over the past 30 years surgical training, including urology training, has changed from the Halstedian apprenticeship-based model to a competency-based one. Simulation-based education (SBE) is an effective, competency-based method for acquiring both technical and non-technical surgical skills and has rapidly become an essential component of urological education. This article introduces the key learning theory underpinning surgical education and SBE, discussing the educational concepts of mastery learning, deliberate practice, feedback, fidelity and assessment. These concepts are fundamental aspects of urological education, thus requiring clinical educators to have a detailed understanding of their impact on learning to assist trainees to acquire surgical skills. The article will then address in detail the current and emerging simulation modalities used in urological education, with specific urological examples provided. These modalities are part-task trainers and 3D-printed models for open surgery, laparoscopic bench and virtual reality trainers, robotic surgery simulation, simulated patients and roleplay, scenario-based simulation, hybrid simulation, distributed simulation and digital simulation. This article will particularly focus on recent advancements in several emerging simulation modalities that are being applied in urology training such as operable 3D-printed models, robotic surgery simulation and online simulation. The implementation of simulation into training programmes and our recommendations for the future direction of urological simulation will also be discussed.

Feasibility of tracking in open surgical simulation

The aim of this study was to develop an adequate tracking method for open surgical training, using tracking of the instrument or hand motions.

An open surgical training model and the SurgTrac application were used to track four separate suturing tasks. These tasks were performed with colour markings of either instruments or fingers, to find the most promising setting for reliable tracking.

Four experiments were used to find the optimal settings for the tracking system. Tracking of instruments was not usable for knot tying by hand. Tracking of fingers seemed to be a more promising method. Tagging the fingers with a coloured balloon-tube, seemed to be a more promising method (1.2–3.0% right hand vs. 9.2–17.9% left hand off-screen) than covering the nails with coloured tape (1.5–3.5% right hand vs. 25.5–55.4% left hand off-screen). However, analysis of the videos showed that redness of the hand was seen as red tagging as well. To prevent misinterpreting of the red tag by redness of the hand, white surgical gloves were worn underneath in the last experiment. The off-screen percentage of the right side decreased from 1.0 to 1.2 without gloves to 0.8 with gloves and the off-screen percentage of the left side decreased from 16.9–17.9 to 6.6–7.2, with an adequate tracking mark on the video images.

This study shows that tagging of the index fingers with a red (right) and blue (left) balloon-tube while wearing surgical gloves is a feasible method for tracking movements during basic open suturing tasks.

The effect of continuous at-home training of minimally invasive surgical skills on skill retention

BACKGROUND

Skill deterioration of minimally invasive surgical (MIS) skills may be prevented by continuous training. The aim of this study is to evaluate whether unsupervised continuous at-home training of MIS skills results in better skill retention compared to no training.

METHODS

Medical doctors followed a two-week interval training for two MIS tasks (precise peg transfer and interrupted suture with knot tying), ending with a baseline test. They were randomly assigned to the no-practice group or continuous-practice group. The latter practiced unsupervised at home every two weeks during the study period. Skill retention was measured after three and six months on both tasks by the total time needed, distance traveled by instruments and LS-CAT score (8 best possible score and > 40 worst score).

RESULTS

A total of 38 participants were included. No significant differences in performance were found at pre-test or baseline. At six months the no-practice group needed more time for the suturing task (309 s vs. 196 s at baseline, p = 0.010) and the LS-CAT score was significantly worse (30 vs. 20 at baseline, p < 0.0001). The continuous-practice group performed the suturing task significantly better than the no-practice group at both three and six months (17 vs. 25, p < 0.001 and 17 vs. 30, p < 0.001) and faster as well (p = 0.034 and p = 0.001).

CONCLUSION

This study shows a skill decay after only a few months of non-use and shows better skill retention after continuous unsupervised at-home practice of MIS skills. This indicates an added value of regular at-home practice of surgical skills.

A Bi-national needs assessment to identify and prioritise procedures in paediatric surgery for simulation-based training

BACKGROUND

Simulation-based education (SBE) has led to significant changes in healthcare education. However, SBE has often been based on available resources and local expertise rather than a systematic approach to curriculum development. The aim of this study was to perform a bi-national needs assessment to identify and prioritise procedures in a paediatric surgery curriculum that can be supported using SBE.

METHOD

A modified 3-round Delphi technique was used to gather consensus from education leaders and trainees in paediatric surgery in Australia and Aotearoa New Zealand (ANZ). Round 1 identified all procedures a newly specialised paediatric surgeon should be able to perform. In Round 2, each procedure was explored for the need for SBE using the Copenhagen Academy for Medical Education and Simulation (CAMES) Needs-Assessment Formula (NAF). This pre-prioritised list from Round 2 was sent back to participants for final exclusion and ranking in Round 3. Results 88 participants were identified and invited. From 174 procedures identified in Round 1, 71 procedures were grouped and categorised for Round 2 using the CAMES NAF. In Round 3, 17 procedures were eliminated resulting in 54 procedures. Appendicectomy, inguinal herniotomy, and central venous access were the highest rank procedures after prioritisation in Round 3. There was a strong correlation (r = 0.99) between the NAF score and the prioritised ranking, as well as between consultants and trainees (r = 0.92 in Round 2 and 0.98 in Round 3).

CONCLUSION

The prioritised list represents a consensus document decided upon by education leaders and stakeholders in paediatric surgery. These procedures should be an integral part of the SBE of paediatric surgeons in the region.

LEVEL OF EVIDENCE

Level V.

LongTerm Outcomes of Three-Port Laparoscopic Right Hemicolectomy Versus Five-Port Laparoscopic Right Hemicolectomy: A Retrospective Study

Purpose

The aim of this study is to compare the long-term outcomes of three-port laparoscopic right hemicolectomy (TPLRC) and five-port laparoscopic right hemicolectomy (FPLRC) with retrospective analysis.

Methods

A total of 182 patients who accepted laparoscopic right hemicolectomy with either three ports (86 patients) or five ports (96 patients) from January 2012 to June 2017 were non-randomly selected and analyzed retrospectively.

Results

More lymph nodes were harvested in the TPLRC group than in the FPLRC group [17.5 (7), 14 (8) ml, p < 0.001]. There was less blood loss in the TPLRC group [50 (80) vs. 100 (125) ml, p = 0.015]. There were no significant differences in the other short-term or oncological outcomes between the two groups. The overall survival and disease-free survival were equivalent.

Conclusions

TPLRC is recommendable as it guarantees short- and long-term equivalent outcomes compared with FPLRC.

Development and validation of a simulator for teaching minimally invasive thoracic surgery in Brazil

Purpose

To develop and validate a chest cavity simulator for teaching video-assited thoracic surgery (VATS).

Methods

The first phase of the study consisted of developing a chest cavity simulator. A quasi-experimental study was performed in the second phase, and 25 surgeons and residents participated in a three-stage pulmonary suture experiment. The videos were recorded and timed. Generalized linear regression models for repeated measures were used to analyze the outcome change over time.

Results

The chest cavity simulator consists of a console simulating the left hemithorax. Among the participants, 96% rated the design, visual aspect, positioning ergonomics, and triangulation of the portals as very good or excellent (face validity). There was a decrease in suturing time in step 1 from 435.7 ± 105 to 355.6 ± 76.8 seconds compared to step 3 (p = 0.001). The evaluation of the simulation effectiveness and performance (content validity) was rated as very good or excellent by 96% ofparticipants. The most experienced surgeon showed significant reduction in procedure time (p = 0.021) (construct validity).

Conclusions

The thoracic cavity simulator is realistic, showing content and construct validity, and can be used in VATS training. The simulation model allowed skill gain in the endoscopic suture.

The Effect of an Interval Training on Skill Retention of High-Complex Low-Volume Minimal Invasive Pediatric Surgery Skills: A Pilot Study

Background: Current training programs for complex pediatric minimal invasive surgery (MIS) are usually bulk training, consisting of 1- or 2-day courses. The aim of this study was to examine the effects of bulk training versus interval training on the preservation of high-complex, low-volume MIS skills. Materials and Methods: Medical students, without prior surgical experience, were randomly assigned to either a bulk or interval training program for complex MIS (congenital diaphragmatic hernia [CDH] and esophageal atresia [EA] repair). Both groups trained for 5 hours; the bulk group twice within 3 days and the interval groups five times in 3 weeks. Skills retention was assessed at 2 weeks, 6 weeks, and 6 months posttraining, using a composite score (0%-100%) based on the objective parameters tracked by SurgTrac. Results: Seventeen students completed the training sessions (bulk n = 9, interval n = 8) and were assessed accordingly. Retention of the skills for EA repair was significantly better for the interval training group than for the bulk group at 6 weeks (P = .004). However, at 6 months, both groups scored significantly worse than after the training sessions for EA repair (bulk 60 versus 67, P = .176; interval 63 versus 74, P = .028) and CDH repair (bulk 32 versus 67, P = .018; interval 47 versus 62, P = .176). Conclusion: This pilot study suggests superior retention of complex pediatric MIS skills after interval training, during a longer period of time, than bulk training. However, after 6 months, both groups scored significantly worse than after their training, indicating the need for continuous training.

Remote training in laparoscopy: a randomized trial comparing home-based self-regulated training to centralized instructor-regulated training

Background

Simulation-based surgical training (SBST) is key to securing future surgical expertise. Proficiency-based training (PBT) in laparoscopy has shown promising results on skills transfer. However, time constraints and limited possibilities for distributed training constitute barriers to effective PBT. Home-based training may provide a solution to these barriers and may be a feasible alternative to centralized training in times of assembly constraints.

Methods

We randomly assigned first-year trainees in abdominal surgery, gynecology, and urology to either centralized instructor-regulated training (CIRT) or home-based self-regulated training (HSRT) in laparoscopy. All participants trained on portable box trainers providing feedback on metrics and possibility for video reviewing. Training in both groups was structured as PBT with graded proficiency exercises adopted from the Fundamentals of Laparoscopic Surgery (FLS). The HSRT group trained at home guided by online learning materials, while the CIRT group attended two training sessions in the simulation center with feedback from experienced instructors. Performance tests consisted of hand–eye and bimanual coordination, suture and knot-tying, and FLS exercises. We analyzed passing rates, training time and distribution, and test performances.

Results

Passing rates were 87% and 96% in the CIRT and HSRT group, respectively. HSRT facilitated distributed training and resulted in greater variation in training times. Task times for hand–eye and bimanual coordination were significantly reduced between pretest and posttest in both groups. Trainees maintained their posttest performances at the 6-month retention test. Our analyses revealed no significant inter-group differences in performances at pretest, posttest, or retention test. Performance improvements in the two groups followed similar patterns.

Conclusion

CIRT and HSRT in laparoscopy result in comparable performance improvements. HSRT in laparoscopy is a feasible and effective alternative to CIRT when offered inside a supportive instructional design. Further research is needed to clarify trainees’ preferences and explore facilitators and barriers to HSRT.

A haptic laparoscopic trainer based on affine velocity analysis: engineering and preliminary results

BACKGROUND

There is a general agreement upon the importance of acquiring laparoscopic skills outside the operation room through simulation-based training. However, high-fidelity simulators are cost-prohibitive and elicit a high cognitive load, while low-fidelity simulators lack effective feedback. This paper describes a low-fidelity simulator bridging the existing gaps with affine velocity as a new assessment variable. Primary validation results are also presented.

METHODS

Psycho-motor skills and engineering key features have been considered e.g. haptic feedback and complementary assessment variables. Seventy-seven participants tested the simulator (17 expert surgeons, 12 intermediates, 28 inexperienced interns, and 20 novices). The content validity was tested with a 10-point Likert scale and the discriminative power by comparing the four groups' performance over two sessions.

RESULTS

Participants rated the simulator positively, from 7.25 to 7.72 out of 10 (mean, 7.57). Experts and intermediates performed faster with fewer errors (collisions) than inexperienced interns and novices. The affine velocity brought additional differentiations, especially between interns and novices.

CONCLUSION

This affordable haptic simulator makes it possible to learn and train laparoscopic techniques. Self-assessment of basic skills was easily performed with slight additional cost compared to low-fidelity simulators. It could be a good trade-off among the products currently used for surgeons' training.

Validation of low-cost models for minimal invasive surgery training of congenital diaphragmatic hernia and esophageal atresia

BACKGROUND

Minimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.

METHODS

Two low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017-December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.

RESULTS

Of all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5-3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).

CONCLUSION

These readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.

TYPE OF STUDY

Prospective study.

LEVEL OF EVIDENCE

Level II.

Development of a posterior sagittal anorectal surgical teaching model

Background

An Anorectal Malformation (ARM) is a rare congenital malformation, which requires proper correction to ensure the best long-term prognosis. These procedures are relatively infrequent and complex, in which a structured approach is important. Therefore, training on an affordable model could be beneficial.

Methods

A low-cost ARM model was developed. The base was reusable and the perineal body disposable. Both expert pediatric surgeons (Experts) and residents/fellows (Target group) were recruited for this study. After testing the model, they completed a questionnaire regarding the realism and didactic value of the model, using a 5-point Likert scale.

Results

Forty-four participants were recruited (Target group n = 20, Experts n = 24). The model has high mean scores of 3.8–4.4 for the total group and even higher on several aspects by the Target group. The experts regarded the haptics and manipulation of the fistula less realistic than the Target group (3.7 versus 4.3, p = 0.021 and 4.2 versus 4.6, p = 0.047). It was considered to be a very good training tool (mean 4.3), without significant differences between the groups.

Conclusions

These results show general consensus that this model is a potent training tool for the component steps of the repair of an ARM with recto-perineal fistula by sagittal approach.

Take-Home Laparoscopy Simulators in Pediatric Surgery: Is More Expensive Better?

Background: To increase complex minimally invasive skills (MIS), frequent training outside the clinical setting is of uttermost importance. This study compares two low-cost pediatric MIS simulators, which can easily be used preclinically. Materials and Methods: The LaparoscopyBoxx is a portable simulator without a tracking system, with costs ranging from €90 to €315. The EoSim simulator has a built-in camera and tracking system and costs range from €780 to €1800. During several pediatric surgical conferences and workshops (January 2017-December 2018), participants were asked to use both simulators. Afterward, they completed a questionnaire regarding their opinion on realism and didactic value, scored on a five-point Likert scale. Results: A total of 50 participants (24 experts and 25 target group, one unknown) evaluated one or both simulators. Both simulators scored well on the questionnaire. The LaparoscopyBoxx scored significantly better regarding the "on screen representation of the instrument actions" (mean 4.2 versus 3.5, P = .001), "training tool for pediatric surgery" (mean 4.4 versus 3.9, P = .005), and "appealing take-home simulator" (mean 4.6 versus 4.0, P = .002). Conclusion: The simulators tested in this study were both regarded an appealing take-home simulator. The LaparoscopyBoxx scored significantly better than the EoSim, even though this is a low budget simulator without tracking capabilities.

Motion analysis for better understanding of psychomotor skills in laparoscopy: objective assessment-based simulation training using animal organs

Background

Our aim was to characterize the motions of multiple laparoscopic surgical instruments among participants with different levels of surgical experience in a series of wet-lab training drills, in which participants need to perform a range of surgical procedures including grasping tissue, tissue traction and dissection, applying a Hem-o-lok clip, and suturing/knotting, and digitize the level of surgical competency.

Methods

Participants performed tissue dissection around the aorta, dividing encountered vessels after applying a Hem-o-lok (Task 1), and renal parenchymal closure (Task 2: suturing, Task 3: suturing and knot-tying), using swine cadaveric organs placed in a box trainer under a motion capture (Mocap) system. Motion-related metrics were compared according to participants’ level of surgical experience (experts: 50 ≤ laparoscopic surgeries, intermediates: 10–49, novices: 0–9), using the Kruskal–Wallis test, and significant metrics were subjected to principal component analysis (PCA).

Results

A total of 15 experts, 12 intermediates, and 18 novices participated in the training. In Task 1, a shorter path length and faster velocity/acceleration/jerk were observed using both scissors and a Hem-o-lok applier in the experts, and Hem-o-lok-related metrics markedly contributed to the 1st principal component on PCA analysis, followed by scissors-related metrics. Higher-level skills including a shorter path length and faster velocity were observed in both hands of the experts also in tasks 2 and 3. Sub-analysis showed that, in experts with 100 ≤  cases, scissors moved more frequently in the “close zone (0  ≤ to < 2.0 cm from aorta)” than those with 50–99 cases.

Conclusion

Our novel Mocap system recognized significant differences in several metrics in multiple instruments according to the level of surgical experience. “Applying a Hem-o-lok clip on a pedicle” strongly reflected the level of surgical experience, and zone-metrics may be a promising tool to assess surgical expertise. Our next challenge is to give completely objective feedback to trainees on-site in the wet-lab.

Electronic supplementary material

The online version of this article (10.1007/s00464-020-07940-7) contains supplementary material, which is available to authorized users.

Assessment of validity evidence for the RobotiX robot assisted surgery simulator on advanced suturing tasks

Background

Robot assisted surgery has expanded considerably in the past years. Compared to conventional open or laparoscopic surgery, virtual reality (VR) training is an essential component in learning robot assisted surgery. However, for tasks to be implemented in a curriculum, the levels of validity should be studied for proficiency-based training. Therefore, this study was aimed to assess the validity evidence of advanced suturing tasks on a robot assisted VR simulator.

Method

Participants were voluntary recruited and divided in the robotic experienced, laparoscopic experienced or novice group, based on self-reported surgical experience. Subsequently, a questionnaire on a five-point Likert scale was completed to assess the content validity. Three component tasks of complex suturing were performed on the RobotiX simulator (Task1: tilted plane needle transfer, Task: 2 intracorporal suturing, Task 3: anastomosis needle transfer). Accordingly, the outcome of the parameters was used to assess construct validity between robotic experienced and novice participants. Composite scores (0–100) were calculated from the construct parameters and corresponding pass/fail scores with false positive (FP) and false negative (FN) percentages.

Results

Fifteen robotic experienced, 26 laparoscopic experienced and 29 novices were recruited. Overall content validity outcomes were scored positively on the realism (mean 3.7), didactic value (mean 4.0) and usability (mean 4.2). Robotic experienced participants significantly outperformed novices and laparoscopic experienced participants on multiple parameters on all three tasks of complex suturing. Parameters showing construct validity mainly consisted of movement parameters, needle precision and task completion time. Calculated composite pass/fail scores between robotic experienced and novice participants resulted for Task 1 in 73/100 (FP 21%, FN 5%), Task 2 in 85/100 (FP 28%, FN 4%) and Task 3 in 64/100 (FP 49%, FN 22%).

Conclusion

This study assessed the validity evidence on multiple levels of the three studied tasks. The participants score the RobotiX good on the content validity level. The composite pass/fail scores of Tasks 1 and 2 allow for proficiency-based training and could be implemented in a robot assisted surgery training curriculum.

Use of a Low-Cost Portable 3D Virtual Reality Gesture-Mediated Simulator for Training and Learning Basic Psychomotor Skills in Minimally Invasive Surgery: Development and Content Validity Study

Background

Simulation in virtual environments has become a new paradigm for surgeon training in minimally invasive surgery (MIS). However, this technology is expensive and difficult to access.

Objective

This study aims first to describe the development of a new gesture-based simulator for learning skills in MIS and, second, to establish its fidelity to the criterion and sources of content-related validity evidence.

Methods

For the development of the gesture-mediated simulator for MIS using virtual reality (SIMISGEST-VR), a design-based research (DBR) paradigm was adopted. For the second objective, 30 participants completed a questionnaire, with responses scored on a 5-point Likert scale. A literature review on the validity of the MIS training-VR (MIST-VR) was conducted. The study of fidelity to the criterion was rated using a 10-item questionnaire, while the sources of content-related validity evidence were assessed using 10 questions about the simulator training capacity and 6 questions about MIS tasks, and an iterative process of instrument pilot testing was performed.

Results

A good enough prototype of a gesture-based simulator was developed with metrics and feedback for learning psychomotor skills in MIS. As per the survey conducted to assess the fidelity to the criterion, all 30 participants felt that most aspects of the simulator were adequately realistic and that it could be used as a tool for teaching basic psychomotor skills in laparoscopic surgery (Likert score: 4.07-4.73). The sources of content-related validity evidence showed that this study’s simulator is a reliable training tool and that the exercises enable learning of the basic psychomotor skills required in MIS (Likert score: 4.28-4.67).

Conclusions

The development of gesture-based 3D virtual environments for training and learning basic psychomotor skills in MIS opens up a new approach to low-cost, portable simulation that allows ubiquitous learning and preoperative warm-up. Fidelity to the criterion was duly evaluated, which allowed a good enough prototype to be achieved. Content-related validity evidence for SIMISGEST-VR was also obtained.

Training the component steps of an extra-corporeal membrane oxygenation (ECMO) cannulation outside the clinical setting

Extra-corporeal membrane oxygenation (ECMO) cannulation can be a stressful procedure because a fast cannulation is vital for the patient’s survival. Therefore, it is important to train the steps of cannulation outside the clinical setting. A relatively low budget, easy to use model, was developed to train the most important steps of an ECMO cannulation. Following this, it was evaluated by experts and target group participants. They all completed a questionnaire regarding their experience and opinions on the ECMO model on general aspects and the training of the component steps, rated on a 5-point Likert scale. Twenty-one participants completed the questionnaire. The features and steps of the model were rated with a mean of 3.9 on average. The haptics of the landscape scored least, with a mean of 3.6, although the haptics of the vessels scored highest with 4.0. The rating of the component steps showed that only ‘opening of the vessels’ was scored significantly different between the expertise levels (means experts: 4.0, target group: 3.4, p = 0.032). This low budget model is considered to be a valid tool to train the component steps of the ECMO cannulation, which could reduce the learning curve in the a stressful clinical setting. Level of evidence: II prospective comparative study.

Training benchmarks based on validated composite scores for the RobotiX robot-assisted surgery simulator on basic tasks

The RobotiX robot-assisted virtual reality simulator aims to aid in the training of novice surgeons outside of the operating room. This study aimed to determine the validity evidence on multiple levels of the RobotiX simulator for basic skills. Participants were divided in either the novice, laparoscopic or robotic experienced group based on their minimally invasive surgical experience. Two basic tasks were performed: wristed manipulation (Task 1) and vessel energy dissection (Task 2). The performance scores and a questionnaire regarding the realism, didactic value, and usability were gathered (content). Composite scores (0–100), pass/fail values, and alternative benchmark scores were calculated. Twenty-seven novices, 21 laparoscopic, and 13 robotic experienced participants were recruited. Content validity evidence was scored positively overall. Statistically significant differences between novices and robotic experienced participants (construct) was found for movements left (Task 1 p = 0.009), movements right (Task 1 p = 0.009, Task 2 p = 0.021), path length left (Task 1 p = 0.020), and time (Task 1 p = 0.040, Task 2 p < 0.001). Composite scores were statistically significantly different between robotic experienced and novice participants for Task 1 (85.5 versus 77.1, p = 0.044) and Task 2 (80.6 versus 64.9, p = 0.001). The pass/fail score with false-positive/false-negative percentage resulted in a value of 75/100, 46/9.1% (Task 1) and 71/100, 39/7.0% (Task 2). Calculated benchmark scores resulted in a minority of novices passing multiple parameters. Validity evidence on multiple levels was assessed for two basic robot-assisted surgical simulation tasks. The calculated benchmark scores can be used for future surgical simulation training.

Development and Validation of a Homemade, Low-Cost Laparoscopic Simulator for Resident Surgeons (LABOT)

Several studies have demonstrated that training with a laparoscopic simulator improves laparoscopic technical skills. We describe how to build a homemade, low-cost laparoscopic training simulator (LABOT) and its validation as a training instrument. First, sixty surgeons filled out a survey characterized by 12 closed-answer questions about realism, ergonomics, and usefulness for surgical training (global scores ranged from 1-very insufficient to 5-very good). The results of the questionnaires showed a mean (±SD) rating score of 4.18 ± 0.65 for all users. Then, 15 students (group S) and 15 residents (group R) completed 3 different tasks (T1, T2, T3), which were repeated twice to evaluate the execution time and the number of users' procedural errors. For T1, the R group had a lower mean execution time and a lower rate of procedural errors than the S group; for T2, the R and S groups had a similar mean execution time, but the R group had a lower rate of errors; and for T3, the R and S groups had a similar mean execution time and rate of errors. On a second attempt, all the participants tended to improve their results in doing these surgical tasks; nevertheless, after subgroup analysis of the T1 results, the S group had a better improvement of both parameters. Our laparoscopic simulator is simple to build, low-cost, easy to use, and seems to be a suitable resource for improving laparoscopic skills. In the future, further studies should evaluate the potential of this laparoscopic box on long-term surgical training with more complex tasks and simulation attempts.

Robot assisted versus laparoscopic suturing learning curve in a simulated setting

Background

Compared to conventional laparoscopy, robot assisted surgery is expected to have most potential in difficult areas and demanding technical skills like minimally invasive suturing. This study was performed to identify the differences in the learning curves of laparoscopic versus robot assisted suturing.

Method

Novice participants performed three suturing tasks on the EoSim laparoscopic augmented reality simulator or the RobotiX robot assisted virtual reality simulator. Each participant performed an intracorporeal suturing task, a tilted plane needle transfer task and an anastomosis needle transfer task. To complete the learning curve, all tasks were repeated up to twenty repetitions or until a time plateau was reached. Clinically relevant and comparable parameters regarding time, movements and safety were recorded. Intracorporeal suturing time and cumulative sum analysis was used to compare the learning curves and phases.

Results

Seventeen participants completed the learning curve laparoscopically and 30 robot assisted. Median first knot suturing time was 611 s (s) for laparoscopic versus 251 s for robot assisted (p < 0.001), and this was 324 s versus 165 (sixth knot, p < 0.001) and 257 s and 149 s (eleventh knot, p < 0.001) respectively on base of the found learning phases. The percentage of ‘adequate surgical knots’ was higher in the laparoscopic than in the robot assisted group. First knot: 71% versus 60%, sixth knot: 100% versus 83%, and eleventh knot: 100% versus 73%. When assessing the ‘instrument out of view’ parameter, the robot assisted group scored a median of 0% after repetition four. In the laparoscopic group, the instrument out of view increased from 3.1 to 3.9% (left) and from 3.0 to 4.1% (right) between the first and eleventh knot (p > 0.05).

Conclusion

The learning curve of minimally invasive suturing shows a shorter task time curve using robotic assistance compared to the laparoscopic curve. However, laparoscopic outcomes show good end results with rapid outcome improvement.

Electronic supplementary material

The online version of this article (10.1007/s00464-019-07263-2) contains supplementary material, which is available to authorized users.