Learning curves, potential and speed in training of laparoscopic skills: a randomised comparative study in a box trainer

Thoracoscopic Repair of Recurrent CDH is Associated with a Significantly Lower Complication Rate and Shorter ICU and Hospital Stay: A Prospective, Propensity Score-Matched Analysis

Congenital diaphragmatic hernia (CDH) is a malformation that significantly impacts neonatal morbidity and mortality. Recurrence after surgical repair remains a potentially life-threatening long-term complication. Conventionally, recurrent CDH has been managed through open surgery. However, thoracoscopic repair (TR) represents a novel alternative for recurrent CDH as it has reduced the length of hospital stay and mortality rate in the primary CDH repair.A prospective, propensity score-matched analysis was conducted on pediatric patients who underwent recurrent CDH repair at the University Hospital Mannheim between 2013 and 2023, to compare the outcomes of laparotomy versus TR. Patients were categorized based on the surgical technique employed. Comparative analysis, including propensity scoring, encompassed outcome measures such as duration of ICU and hospital stays, rate of complications, and operative duration.In total, 703 patients were treated for CDH, of whom 69 children underwent laparotomy (56) or TR (16) for CDH recurrence. After propensity score matching, TR group demonstrated a significantly shorter duration of surgery (178 [93-311] versus 225 [113-450] min, p = 0.042), reduced ICU stay (0 [0-10] versus 1 (0-69) days, p = 0.011), and decreased overall hospital stay (6 [3-34] versus 12 [7-40] days, p = 0.001). Moreover, the postoperative complications were significantly lower in the TR group (21.43% versus 73.68%, p = 0.003).TR for recurrent CDH repair is associated with shorter operation times, reduced ICU and overall hospital stays, and fewer complications compared with laparotomy. These findings suggest that TR may be preferable for the management of recurrent CDH, warranting larger randomized controlled studies to confirm the long-term safety and efficacy of this approach.

Effects of Systematically Guided vs. Self-Directed Laparoscopic Box Training on Learning Performances: An Observational Study

Introduction

Minimally invasive surgery is increasing in all fields of surgery. It is currently unknown whether structured training is superior to self-directed training. The aim of this study is to analyze the enhancement of surgical skills in laparoscopy box trainers in a systematically guided training program compared to self-directed training.

Material and Methods

Two groups of 40 medical students were included in the study between 04/2021 and 01/2023. Each training session on the laparoscopic box trainer (Medishield BV, NL) was automatically protocolled, including time, force, and path length. The structured group consisted of 21 students working in peer tandem, while the self-directed group consisted of 19 last-year students in their four-month elective. The observational study was conducted in an ecological study design.

Results

The self-directed cohort completed an average of 15 training sessions compared to the structured cohort's 10 sessions. All participants in both groups improved in time, path length, and force. The structured cohort showed nearly linear improvement, while the self-directed cohort had high deviation in results.

Conclusion

Supervision and collaborative work positively influence laparoscopic training success. Mere availability of training does not exploit the potential of laparoscopic box trainers. Curriculums for young surgeons or medical students should include institutionalized training with a structured schedule and a training partner for improved outcomes.

3D vs. 2D-4 K: Performance and self-perception of laparoscopic novices in a randomized prospective teaching intervention using standard tasks and box trainers

OBJECTIVE

The use of three-dimensional (3D) laparoscopy in surgical practice and training has been an area of research and discussion. Studies have suggested that 3D vision can improve speed and precision compared to traditional two-dimensional (2D) displays, while other authors found no benefits on the learning curves of laparoscopic novices. Modern two-dimensional laparoscopy with a resolution of 3840 × 2160 pixels (2D-4 K) seems to improve laparoscopic view and helps learners orient without stereopsis. However, evidence comparing these systems for laparoscopic training is limited. Therefore, the impact of viewing mode (2D-4 K vs. 3D) on learning and task proficiency remains unclear.

DESIGN

We performed a two-hour teaching intervention on basic laparoscopic skills for novices. In this parallel group randomized study, we randomly assigned learners to 2D-4 K or 3D teaching and performed tasks of increasing difficulty and complexity using standard laparoscopy box trainers. Before the last and most challenging task, learners had to crossover to the other laparoscopy setup. Our hypothesis was that learners would be faster and more precise when using a 3D setup. The primary endpoint was task proficiency measured by speed and failure rate. Secondary outcomes were performance using the viewing mode of the other group without familiarization, self-perception, and career aspirations before and after the teaching intervention, expressed on a Likert scale.

SETTING

The study was performed by the Department of General, Visceral and Thoracic Surgery at the German Armed Forces Hospital Ulm, which is an academic teaching hospital of the University of Ulm.

PARTICIPANTS

Thirty-eight laparoscopic novices, including medical students and junior residents, participated voluntarily in this teaching intervention. Group allocation was performed via the virtual coin flip method. Apparently, participants and tutors were not blinded to group assignment. No formal approval by the ethics committee was needed for this noninvasive study in compliance with the World Medical Association Declaration of Helsinki as discussed with the ethics committee of the University of Ulm.

RESULTS

Thirty-eight laparoscopy novices were randomized in the study. The 3D group (n = 19) was significantly faster than the 2D-4 K group (n = 19) (p = .008) in a standard box trainer model, with 134.45 ± 41.45 s vs. 174.99 ± 54.03 s for task 1 and 195.97 ± 49.78 s vs. 276.56 ± 139.20 s for task 2, and the effect was consistent throughout the learning curve. The failure rate was not significantly affected by the viewing mode. After crossover to the other laparoscopy system, precision and time were not significantly different between the groups. Learners rated the difficulty of laparoscopy lower on a Likert scale after having two hours of basic laparoscopy training. The study was funded by the hospital's teaching budget.

CONCLUSIONS

Laparoscopic novices can benefit from a 3D laparoscopy training setup. Exclusive 3D training prior to a complex task on a 2D-4 K setup does not negatively affect the learner's performance.

Transferability of laparoscopic skills acquired from three-dimensional high-definition and ultra-high definition endovision system to two-dimensional high-definition endovision system: an ex-vivo randomized study

Three-dimensional high-definition (3D HD) and ultra-high-definition (4 K HD) endovision systems are rapidly adopted in academic setting. However, transferability of laparoscopic skills acquired from these systems to two-dimensional high-definition (2D HD) endovision system is not known. Forty stereo-enabled surgical residents were randomized into two groups. They performed three standardized surgical tasks, Task 1(Peg transfer), Task 2(Precision touch on uneven surface) and Task 3(Surgical knotting on rubber tube) for 15 repetitions using either 3D HD or 4 K HD. Both groups then performed the same tasks using 2D HD for 5 repetitions. Their performances were evaluated for execution time (speed) and error scores (safety). The residents in 3D HD group performed all three tasks significantly faster than residents in 4 K HD group with comparable error scores. The time taken to complete the tasks on 2D HD were comparable between residents trained in 3D HD and 4 K HD in two out of three tasks (p = 0.027, P = 0.115, p = 0.368 in task 1, 2 and 3 respectively). However, in two out of three tasks, residents trained on 3D HD committed significantly more errors than residents trained on 4 K HD (p < 0.0001, p < 0.001 in task 1 and task 2 respectively). Skill acquired on 4 K HD seems transferable to 2D HD environment. Participants trained in 3D HD made more errors while performing the tasks in 2D HD. It may be prudent to offer additional training on 2D HD to residents trained on 3D HD for safer laparoscopic surgical practice.

Optimizing laparoscopic and robotic skills through simulation in participants with limited or no prior experience: a systematic review and meta-analysis

BACKGROUND

Simulation is an innovative tool for developing complex skills required for surgical training. The objective of this study was to determine the advancement of laparoscopic and robotic skills through simulation in participants with limited or no previous experience.

METHODS

This is a systematic review and meta-analysis of randomized controlled trials (RCTs) in keeping with the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We conducted searches using MEDLINE (PubMed), Web of Science, Google Scholar, and Cochrane Library. Variables analyzed were study characteristics, participant demographics, and characteristics of the learning program. Our main measures were effectiveness, surgical time, and errors. These were reported using standardized mean difference (SMD) with 95% CI (P < .05). Secondary measures included skill transfer and learning curve.

RESULTS

A total of 17 RCTs were included and comprised 619 participants: 354 participants (57%) were in the simulation group and 265 (43%) in the control group. Results indicated that laparoscopic simulation effectively enhanced surgical skills (SMD, 0.59 [0.18-1]; P = .004) and was significantly associated with shorter surgical duration (SMD, -1.08 [-1.57 to -0.59]; P < .0001) and a fewer errors made (SMD, -1.91 [-3.13 to -0.70]; P = .002). In the robotic simulation, there was no difference in effectiveness (SMD, 0.17 [-0.19 to 0.52]; P = .36) or surgical time (SMD, 0.27 [-0.86 to 1.39]; P = .64). Furthermore, skills were found to be transferable from simulation to a real-life operating room (P < .05).

CONCLUSION

Simulation is an effective tool for optimizing laparoscopic skills, even in participants with limited or no previous experience. This approach not only contributes to the reduction of surgical time and errors but also facilitates the transfer of skills to the surgical environment. In contrast, robotic simulation fails to maximize skill development, requiring previous experience in laparoscopy to achieve optimal levels of effectiveness.

Does practice make perfect? Laparoscopic training mainly improves motion efficiency: a prospective trial

Training improves skills in minimally invasive surgery. This study aimed to investigate the learning curves of complex motion parameters for both hands during a standardized training course using a novel measurement tool. An additional focus was placed on the parameters representing surgical safety and precision. Fifty-six laparoscopic novices participated in a training course on the basic skills of minimally invasive surgery based on a modified Fundamentals of Laparoscopic Surgery (FLS) curriculum. Before, twice during, and once after the practical lessons, all participants had to perform four laparoscopic tasks (peg transfer, precision cut, balloon resection, and laparoscopic suture and knot), which were recorded and analyzed using an instrument motion analysis system. Participants significantly improved the time per task for all four tasks (all p < 0.001). The individual instrument path length decreased significantly for the dominant and non-dominant hands in all four tasks. Similarly, both hands became significantly faster in all tasks, with the exception of the non-dominant hand in the precision cut task. In terms of relative idle time, only in the peg transfer task did both hands improve significantly, while in the precision cut task, only the dominant hand performed better. In contrast, the motion volume of both hands combined was reduced in only one task (precision cut, p = 0.01), whereas no significant improvement in the relative time of instruments being out of view was observed. FLS-based skills training increases motion efficiency primarily by increasing speed and reducing idle time and path length. Parameters relevant for surgical safety and precision (motion volume and relative time of instruments being out of view) are minimally affected by short-term training. Consequently, surgical training should also focus on safety and precision-related parameters, and assessment of these parameters should be incorporated into basic skill training accordingly.

Safety of Three-Dimensional versus Two-Dimensional Laparoscopic Hysterectomy during the COVID-19 Pandemic

BACKGROUND

The COVID-19 pandemic has resulted in a significant decrease in the number of surgical procedures performed. Therefore, it is important to use surgical methods that carry the lowest possible risk of virus transmission between the patient and the operating theater staff.

AIM

Safety evaluation of three-dimensional (3D) versus two-dimensional (2D) laparoscopic hysterectomy during the COVID-19 pandemic.

METHODS

44 patients were assigned to a prospective case-control study. They were divided either to 3D (n = 22) or 2D laparoscopic hysterectomy (n = 22). Fourteen laparoscopic supracervical hysterectomies (LASH) and eight total laparoscopic hysterectomies (TLH) were performed in every group. The demographic data, operating time, change in patients' hemoglobin level and other surgical outcomes were evaluated.

RESULTS

3D laparoscopy was associated with a significantly shorter operating time than 2D. (3D vs. 2D LASH 70 ± 23 min vs. 90 ± 20 min, p = 0.0086; 3D vs. 2D TLH 72 ± 9 min vs. 85 ± 9 min, p = 0.0089). The 3D and 2D groups were not significantly different in terms of change in serum hemoglobin level and other surgical outcomes.

CONCLUSIONS

Due to a shorter operating time, 3D laparoscopic hysterectomy seems to be a safer method both for both the surgeon and the patient. Regarding terms of possible virus transmission, it may be particularly considered the first-choice method during the COVID-19 pandemic.

Directed information flow during laparoscopic surgical skill acquisition dissociated skill level and medical simulation technology

Virtual reality (VR) simulator has emerged as a laparoscopic surgical skill training tool that needs validation using brain-behavior analysis. Therefore, brain network and skilled behavior relationship were evaluated using functional near-infrared spectroscopy (fNIRS) from seven experienced right-handed surgeons and six right-handed medical students during the performance of Fundamentals of Laparoscopic Surgery (FLS) pattern of cutting tasks in a physical and a VR simulator. Multiple regression and path analysis (MRPA) found that the FLS performance score was statistically significantly related to the interregional directed functional connectivity from the right prefrontal cortex to the supplementary motor area with F (2, 114) = 9, p < 0.001, and R² = 0.136. Additionally, a two-way multivariate analysis of variance (MANOVA) found a statistically significant effect of the simulator technology on the interregional directed functional connectivity from the right prefrontal cortex to the left primary motor cortex (F (1, 15) = 6.002, p = 0.027; partial η² = 0.286) that can be related to differential right-lateralized executive control of attention. Then, MRPA found that the coefficient of variation (CoV) of the FLS performance score was statistically significantly associated with the CoV of the interregionally directed functional connectivity from the right primary motor cortex to the left primary motor cortex and the left primary motor cortex to the left prefrontal cortex with F (2, 22) = 3.912, p = 0.035, and R² = 0.262. This highlighted the importance of the efference copy information from the motor cortices to the prefrontal cortex for postulated left-lateralized perceptual decision-making to reduce behavioral variability.

Real-Time 3D Tracking of Laparoscopy Training Instruments for Assessment and Feedback

Assessment of minimally invasive surgical skills is a non-trivial task, usually requiring the presence and time of expert observers, including subjectivity and requiring special and expensive equipment and software. Although there are virtual simulators that provide self-assessment features, they are limited as the trainee loses the immediate feedback from realistic physical interaction. The physical training boxes, on the other hand, preserve the immediate physical feedback, but lack the automated self-assessment facilities. This study develops an algorithm for real-time tracking of laparoscopy instruments in the video cues of a standard physical laparoscopy training box with a single fisheye camera. The developed visual tracking algorithm recovers the 3D positions of the laparoscopic instrument tips, to which simple colored tapes (markers) are attached. With such system, the extracted instrument trajectories can be digitally processed, and automated self-assessment feedback can be provided. In this way, both the physical interaction feedback would be preserved and the need for the observance of an expert would be overcome. Real-time instrument tracking with a suitable assessment criterion would constitute a significant step towards provision of real-time (immediate) feedback to correct trainee actions and show them how the action should be performed. This study is a step towards achieving this with a low cost, automated, and widely applicable laparoscopy training and assessment system using a standard physical training box equipped with a fisheye camera.

Study on augmented reality for robotic surgery bedside assistants

Robotic surgery bedside assistants play an important role in robotic procedures by performing intra-corporeal tasks while accommodating the physical presence of the robot. We hypothesized that an augmented reality headset enabling 3D intra-corporeal vision while facing the surgical field could decrease time and improve accuracy of robotic bedside tasks. Bedside assistants (one physician assistant, one medical student, three surgical trainees, and two attending surgeons) performed validated tasks within a mock abdominal cavity with a surgical robot docked. Tasks were performed with a bedside monitor providing 2D or 3D vision, or an optical see-through head-mounted augmented reality device with 2D or 3D vision. The effect of augmented reality device resolution on performance was also evaluated. For the simplest task of touching a straw, performance was generally high, regardless of mode of visualization. With more complex tasks, including stapling and pulling a ring along a path, 3D augmented reality decreased time and number of errors per task. 3D augmented reality allowed the physician assistant to perform at the level of an attending surgeon using 3D augmented reality (p = 0.08). All participants had improved times for the ring path task with better resolution (lower resolution 23 ± 11 s vs higher resolution 14 ± 4 s, p = 0.002). 3D augmented reality vision with high resolution decreased time and improved accuracy of more complex tasks, enabling a less experienced robotic surgical bedside assistant to function similar to attending surgeons. These data warrant further study with additional complex tasks and bedside assistants at various levels of training.

Learning Pattern of Two-Dimensional, Three-Dimensional, and Ultra-High-Definition Endovision System on Standardized Phantom Tasks: An Ex Vivo Randomized Study

Introduction: Three-dimensional (3D), high-definition (HD), and ultra-high-definition (4K HD) are recent additions over regular HD technology for laparoscopic surgery. The aim of this study was to evaluate the learning pattern of these systems on standardized phantom tasks. Methodology: Forty-five stereo-enabled resident doctors were randomly assigned into three groups. They performed three validated tasks, precision touch on flat surface, precision touch on uneven surface, surgical knot on rubber tube using either two-dimensional (2D) HD, 3D HD, or 4K HD Endovision systems. Each task was repeated 20 times. Data from four consecutive repetitions were pooled to make five blocks. Split group analysis by comparing the consecutive blocks in execution time and errors were made to see the learning pattern. A significant difference was accepted as continuous learning while no significant difference was accepted as learning stabilization. Result: Operating time was stabilized in two tasks after third block in 2D HD, one task after fourth block in 4K HD. There was continuous learning in all tasks with 3D HD. The 3D HD group was significantly faster than 2D HD and 4K HD in most of the tasks on fifth block. The error scores were similar between the consecutive blocks in 4K HD. It was stabilized after second block in 2D HD group and third block on 3D HD. Conclusion: The 3D HD Endovision system has more potential of faster execution of a task, but need more practice to reach similar safety profile. The 4K HD reached the safety plateau with minimal repetitions.

Associations Between Binocular Depth Perception and Performance Gains in Laparoscopic Skill Acquisition

The ability to perceive differences in depth is important in many daily life situations. It is also of relevance in laparoscopic surgical procedures that require the extrapolation of three-dimensional visual information from two-dimensional planar images. Besides visual-motor coordination, laparoscopic skills and binocular depth perception are demanding visual tasks for which learning is important. This study explored potential relations between binocular depth perception and individual variations in performance gains during laparoscopic skill acquisition in medical students naïve of such procedures. Individual differences in perceptual learning of binocular depth discrimination when performing a random dot stereogram (RDS) task were measured as variations in the slope changes of the logistic disparity psychometric curves from the first to the last blocks of the experiment. The results showed that not only did the individuals differ in their depth discrimination; the extent with which this performance changed across blocks also differed substantially between individuals. Of note, individual differences in perceptual learning of depth discrimination are associated with performance gains from laparoscopic skill training, both with respect to movement speed and an efficiency score that considered both speed and precision. These results indicate that learning-related benefits for enhancing demanding visual processes are, in part, shared between these two tasks. Future studies that include a broader selection of task-varying monocular and binocular cues as well as visual-motor coordination are needed to further investigate potential mechanistic relations between depth perceptual learning and laparoscopic skill acquisition. A deeper understanding of these mechanisms would be important for applied research that aims at designing behavioral interventions for enhancing technology-assisted laparoscopic skills.