Brief Communication
Hell J Surg. 2024 Oct-Dec;94(4):220–226
doi: 10.59869/24050
Ellada Akritidou, Anastasia Pikouli, Charalampos M. Charalampous, Constantinos Nastos, Dionysios Dellaportas, Panagis M. Lykoudis, Emmanouil Pikoulis
Third Department of Surgery, University Hospital Attikon, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
Correspondence: Charalampos M. Charalampous, 1, Rimini Street, 12462, Chaidari, Attiki, Greece, Tel.: +30 6984977769, e-mail: chacharalampous@gmail.com
ABSTRACT
Background: Surgical skills training has evolved with the wide implementation of modalities such as Virtual Reality (VR) laparoscopic simulators. One of the most demanding skills, laparoscopic suturing, requires innovative tools with established curricula for training and assessment of trainees. Simulators allow practice of the associated techniques in a complication-free environment, prior to application in the operating theatre.
Materials and Methods: The program methodology is divided into development, validation and implementation. The development phase will include a cohort of ten experts and a cohort of twenty novice trainees performing a group of six exercises at a single Simulation Center. Analysis of their performance will be used to test Construct and Face Validity of the program. For validation, similar cohorts will be formed in two different Simulation Centers, using the same simulator, and data acquired will be assessed based on the “Messick’s framework”.
Results: Data from the development and validation phase will be investigated to identify concordance between the findings in independent populations. The implementation phase will take place in all three Simulation Centers, followed by performance analysis, in accordance with the procedure described during development and validation phases.
Conclusions: VR simulators are transformative in simplifying complex information and engaging trainees effectively. While promising, achieving VR’s full potential requires ongoing efforts to refine haptic feedback realism, develop evidence-based curriculum, and comprehensively evaluate effectiveness. Such validated training curricula will ultimately result in more efficient skill acquisition, and eventually better patient outcomes.
Key Words: Laparoscopic suturing, virtual reality (VR), simulation, intracorporeal knot-tying, surgical training
Submission: 02.04.2025, Acceptance: 24.06.2025
The emerging need for training future surgeons and evaluating their acquired skills in a safe and controlled environment has led to the development of simulation. Simulation has become an integral part of Medical training with the use of “box trainers” and more advanced modalities such as Virtual Reality (VR) simulators. Laparoscopic, robotic and arthroscopic procedures form the cornerstone simulation-based training. VR simulators enable training in both basic skills and full operations, according to preset objective criteria [1-3]. Currently available validated training programs cover the laparoscopic cholecystectomy, colectomy and appendicectomy. However, a program for laparoscopic suturing, a fundamental skill required by a surgeon, is not yet available. The index study aims to address this gap and, subsequently, contribute to a more structured and efficient training for future surgical trainees.
Laparoscopic suturing is one of the most demanding skills in surgery. Therefore, it is essential for surgical trainees to get familiar with the associated techniques in a complication-free environment, prior to application in the operating theatre. Simulation tools, such as box trainers, have played a significant role in achieving this goal. However, this kind of simulation is ideal for the initial development of fundamental skills. VR simulators using haptic feedback, visual guidance and objective performance criteria, offer a more holistic training and enable objective assessment, before trainees apply their skills in the operating room.
By applying established scientific research methods, such as recording the performance of both trainees and experienced surgeons, a structured, validated virtual reality simulation training curriculum for laparoscopic suturing techniques can be designed and implemented.
METHODOLOGY I – PROGRAM DEVELOPMENT
Τhe first phase of developing a virtual reality-based simulation curriculum for laparoscopic suturing training will take place at the “Minimally Invasive Surgery Simulation Center”, AKISA, School of Medicine, NKUA, Athens, Greece (May 2025-September 2025). The hardware equipment will be the VR simulator LAP Mentor III (Simbionix Corporation, Cleveland, Ohio, USA). The educational program will be based on the Basic Suturing Module v. 2.0.1.62 software.
The first phase will include thirty participants, divided into two cohorts based on predefined selection criteria. The first cohort will include ten experts, defined as specialised surgeons, who perform over 25 operations involving laparoscopic suturing yearly and without previous experience in VR simulators. The second cohort will include twenty non-experts, defined as medical students or residents, who have completed the Basic Skills program in the VR simulator but have not practiced laparoscopic suturing. As for inclusion criteria for the non-expert cohort, there will be no restriction with regards to year of residency. Since they will originate from a healthcare system lacking a structured training program, such a stratification does not correspond to surgical experience.
The above-mentioned group of thirty participants will be performing six exercises with sub-exercises. For both groups, the frequency of practice will be one attempt per day, lasting approximately 40 minutes. Data analysis will be performed on a station-basis; therefore, it will not be affected by the completed stations on each session. For experts, two attempts will be required for two consecutive days, and for trainees three attempts per week for at least five weeks.
Recording and storage of data
Each participant’s performance data will be extracted directly from the simulator and the manufacturer’s existing software and stored in a spreadsheet file (Microsoft Excel, Microsoft, Redmond, Washington, USA). Data will be anonymised using a Key / Ascending number. Only the Principal Investigator and the Scientific Manager of the protocol will have access to the matching file. Each participant will complete a written consent form for the purpose of using their performance data in this research project.
Ethical statement
Appropriate institutional approval was granted from the Bioethics Committee of Attikon University Hospital.
Statistical processing
The statistical processing of the data will be done using the statistical processing package SPSS v25 (IBM, Chicago, Illinois, USA). Descriptive statistics will consist of the median and interquartile range for numeric variables, and the absolute number and percentage of the total for non-numeric variables. The normality of the data distribution will be examined by visual analysis of frequency histograms, and by applying the Kolmogorov-Smirnov test. For continuous numerical data with a normal distribution, parametric tests (t-test, ANOVA, Spearman correlation) will be applied. For continuous numerical data with a non-normal distribution, non-parametric tests (Mann-Whitney-U test, Independent Samples Median Test) will be applied.
For non-numerical data, χ2 and Fisher’s exact test will be used. The learning curves will be analysed using the serial comparison method, the CUSUM analysis method or the ROC/AUC method, depending on the characteristics of the data. Where appropriate, two-tailed statistical tests will be applied. P-values <0.05 will be considered statistically significant, and p-values from 0.05 to 0.1 will be considered statistically indicative.
Program planning
After the completion of the statistical analysis of the data, the program planning will take place. The estimated duration of the program will be determined based on the average time (weeks) required for trainees’ learning curves to approach the baseline of success, defined by experts’ opinion, relevant literature, and experts’ performance. The success/pass baseline will be set based on the experts’ performance data and adjusted to the trainees’ level (±1 SD). Major parameters that will be assessed are divided in economy parameters (total time, number of movements of each hand), effectiveness parameters (completion of task, accuracy of needle passage, quality of knots) and safety parameters (tissue strain, needle outside the field of view). More details are included in the Appendix. The “Construct validity” [3,4] and “Face validity” [4] parameters of the training program will be tested with two different methods. The validity of the program will be assessed based on the “Messick’s framework” which is now the most widely accepted method [5,6].
METHODOLOGY II – PROGRAM VALIDATION
The second phase, including the validation of the program, will take place after preliminary agreement with “The Paul Shrank Screen-Based Simulation Centre”, Royal Free Hospital, University College London (UCL), London, UK and at the “Center for Laparoscopic Surgery Simulation”, University Surgery Clinic, Hamburg University, Hamburg, Germany (October 2025 –March 2026). Both centers are equipped with the same model of the aforementioned simulator.
Similarly to the first phase (Methodology I), the program validation will involve thirty participants (10 experts, 20 non-experts) with the same selection criteria, as described in the program development phase. The practicing schedule will be as formulated in the previous phase.
After the exercise program is completed, data collection and analysis will be conducted. Data recording, storage and statistical analysis will follow the same procedure as analysed in Methodology I stage.
Formulation of results
The alignment between the findings of the current phase with those of the first phase (Program Development) will be investigated in order to formulate the application of the program in independent populations.
METHODOLOGY III – PROGRAM IMPLEMENTATION
The third phase, involving the implementation of the virtual reality simulation program for laparoscopic suturing training, is scheduled to take place at the “Minimally Invasive Surgery Simulation Center”, AKISA, School of Medicine, NKUA, Athens, Greece and after preliminary agreement at “The Paul Shrank Screen-Based Simulation Centre”, Royal Free Hospital, University College London (UCL), London, UK, and at the “Center for Laparoscopic Surgery Simulation”, University Surgery Clinic, Hamburg University, Hamburg, Germany (May 2026-August 2026).
The target group will include specialised surgeons, residents and medical students. In total, 60 participants will complete a written consent form for the purpose of using their performance data in this research project. Data collection, data recording, statistical analysis and performance results will be conducted in accordance with the procedure described in Methodology I and II.
Additionally, each participant will complete a questionnaire before the start of the program to capture their expectations, and again after the completion of the program provide feedback on the program, including comments, observations and suggestions.
No other training programs have been studied and/or reported in current literature in a VR/high fidelity environment. The most important challenge is to recruit expert surgeons with similar educational background, in order to demonstrate concordance between them. In case of failure, more experts will need to be recruited. Cost and enrollment are very important topics, which require a separate, implementation study, that is also a future study topic, following development and validation.
Focus group
After the implementation of the program, the participants will take part in focus groups to express and discuss their opinion on the specific learning program, as well as to make suggestions for possible improvements. The coordinator of each group will not have taken part in the development, validation or implementation of the program. Each group will consist of six-eight people. The number of specialists, trainees and students in each group will be approximately the same. The number of males and females in each group will be approximately the same. The duration of the session will be one-two hours and questions will be decided based on the results of the first two phases of the study, and the current literature.
The analysis of the data collected by the Focus Group will be performed with descriptive qualitative methods [7].
COMMUNICATION OF RESULTS
The findings of this study and the developed learning curriculum will be presented in seminars and conferences, as well as in international scientific journals. Key areas of discussion and further applications will include evaluating the efficacy of integrating laparoscopic suturing simulation in comprehensive training programs, examining the effectiveness of combining it with classical simulation tools such as box trainers and mannequins, and finally, assessing its impact on actual clinical practice. The latter will include translational research by comparing trainees’ actual performance in the operating theatre before and after attending the curriculum.
CONFLICTS OF INTEREST
None.
REFERENCES
- Aggarwal R, Crochet P, Dias A, Misra A, Ziprin P, Darzi A. Development of a virtual reality training curriculum for laparoscopic cholecystectomy. Br J Surg. 2009;96(9):1086-93. Doi:10.1002/bjs.6679
- Sinitsky DM, Fernando B, Potts H, Lykoudis P, Hamilton G, Berlingieri P. Development of a structured virtual reality curriculum for laparoscopic appendicectomy. Am J Surg. 2020;219(4):613-21. Doi:10.1016/j.amjsurg.2019.04.020
- Wynn G, Lykoudis P, Berlingieri P. Development and implementation of a virtual reality laparoscopic colorectal training curriculum. Am J Surg. 2018;216(3):610-17. Doi:10.1016/j.amjsurg.2017.11.034
- Feeley A, Feeley I, Merghani K, Sheehan E. A pilot study to evaluate the face & construct validity of an orthopaedic virtual reality simulator. Injury. 2021;52(7):1715-20. Doi:10.1016/j.injury.2021.04.045
- Cook DA, Hatala R. Validation of educational assessments: a primer for simulation and beyond. Adv Simul (Lond). 2016 Dec;1:31. Doi: 10.1186/s41077-016-0033-y.
- Goldenberg M, Lee JY. Surgical Education, Simulation, and Simulators-Updating the Concept of Validity. Curr Urol Rep. 2018 May;19(7):52. Doi: 10.1007/s11934-018-0799-7.
- Crothers K, Shahrir S, Kross EK, et al. Patient and clinician recommendations to improve communication and understanding of lung cancer screening results. Chest. 2023;163(3):707-18. Doi:10.1016/j.chest.2022.09.038
APPENDIX
Exercise 1 –
Needle Loading and Suture Placement.
The goal of the exercise is to position the needle at the desired angle in the needle holder jaw. This exercise teaches the principles of needle loading and spatial orientation that allow for correct needle insertion into the tissue, as well as needle manipulation inside the tissue.
At the beginning of each exercise the participant chooses which will be the dominant hand and the exercise is adjusted accordingly.
- Sub-task 1- Picking up the needle by grasping it at the rear third with the dominant needle holder.
- Sub-task 2 – Loading thread with the passive needle holder.
- Sub-task 3 Picking up the needle by grasping its tip with the passive needle holder.
- Sub-task 4- Loading thread with the dominant needle holder.
Objectives:
- To acquire the skill of picking up the needle from different locations on the tissue surface.
- To acquire the skill of forehand manipulation of the needle.
- To position the needle in the needle holder at 90º relative to the suture line.
- To learn how to approach different suture line orientations.
- To position the needle tip at 90º to the tissue surface.
- To practice “taking the bite” in one or two sequences.
- To use the lifting technique for passing the needle through the tissue.
- To insert and extract the needle in line with its curvature.
- To practice thread withdrawal techniques (short withdraws, pulley).
- To leave a relatively short tail of thread.
- To prepare the thread for the formation of a knotting loop (C loop).
- To work with the needle and the needle holders in view at all times.
Exercise 2 –
Continuous sutures.
The goal of the exercise is to practice the principles of continuous suture – a series of stitches performed with one thread along a suture line.
At the beginning of each exercise the participant chooses which will be the dominant hand and the exercise is adjusted accordingly. Each tutorial begins with the thread already fixed to the tissue at the top of the suture line.
Objectives:
- To acquire the skills to perform continuous suturing accurately and efficiently.
- To pick the needle up from different locations on the tissue surface.
- To learn how to approach different suture line orientations.
- To pass the needle at equal width, depth and intervals in order to create a regular and symmetrical closure.
- To practice “taking the bite” in one or two sequences.
- To use the lifting technique to pass the needle through the tissue.
- To learn thread withdrawal techniques (short withdraws, pulley).
- To tighten the suture after each passage of the needle.
Exercise 3 –
Knot Tying – Half Knot
The goal of the exercise is to learn how to form the half knot. This exercise teaches different methods to form a half-knot using either the “over-wrap” or the “under-wrap” techniques.
For the “over-wrap” technique: The passive needle holder is placed over the C loop formed by the thread. The thread is then wrapped first over and then under the passive needle holder.
For the “under-wrap” technique: The passive needle holder is placed under the C loop created by the thread. With the thread positioned over the passive needle holder, it is then wrapped under it, then over it again.
At the beginning of each exercise the participant chooses which will be the dominant hand and the exercise is adjusted accordingly.
Objectives:
- To practice creating a C loop with correct shape and orientation.
- To leave a relatively short tail of thread when creating the knot.
- To manipulate both needle holders close to the sutured tissue.
- To work with both needle holders during the wrapping process.
- To use both needle holders to tighten the knot, applying force mainly by the dominant needle holder.
Exercise 4 –
Knot Tying – Square Knot
The goal of the exercise is to learn how to form the square knot either with the ‘over-wrap’ or the ‘under-wrap techniques. A square knot is defined as 2 opposing single half knots.
At the beginning of each exercise the participant chooses which will be the dominant hand and the exercise is adjusted accordingly.
4 consecutive sub-exercises.
- Sub-task 1 – Square knot – forming two half knots, each using a C loop in the opposite direction, with one over-wrapped loop.
- Sub-task 2 – Square knot – forming two half knots, each using a C loop in the opposite direction, with one under-wrapped loop.
- Sub-task 3 – Square knot – forming two half knots, each using a C loop in the same direction, one with an over-wrapped loop and the other with an under-wrapped loop.
- Sub-task 4- Square knot – forming two half knots, each using a C loop in the same direction, one with an under-wrapped loop and the other with an over-wrapped loop.
Objectives:
- To acquire the skills to create a C loop with correct shape and orientation.
- To leave a relatively short tail of thread when creating the knot.
- To manipulate both needle holders close to the sutured tissue.
- To work with both needle holders during the wrapping process.
- To use both needle holders to tighten the knot, applying force mainly by the dominant needle holder.
- To practice cutting the thread using scissors.
Exercise 5 –
Knot Tying – Ligature and Surgeon’s Knot
The goal of the exercise is to learn how to form a ligature knot and a surgeon’s knot using over-wrap and under-wrap techniques.
The ligature knot is similar to the square knot, differing only in the first half knot which is double instead of single. Its advantage over the square knot is in providing greater holding strength.
The surgeon’s knot is a standard intracorporeal knot tying technique, used in endoscopic surgery. The first half knot is double, as in the ligature knot. The second and third are single half knots tied in opposite directions.
At the beginning of each exercise the participant chooses which will be the dominant hand and the exercise is adjusted accordingly.
- Sub-task 1 – Forming two half knots, each using a C loop in an opposite direction with one a double over-wrapped loop and one with an over-wrapped loop.
- Sub-task 2 – Forming three half knots, each using a C loop in the same direction; one with a double over-wrapped loop, the second with an under-wrapped loop, and the third with an over-wrapped loop.
- Sub-task 3 – Forming three half knots, each using a C loop in the same direction: one with a double under-wrapped loop, the second with an over-wrapped loop and the third with an under-wrapped loop.
Objectives:
To acquire the skills required for forming a surgeon’s knot, used in continuous and interrupted suture.
Exercise 6 –
Continuous/Interrupted Suture
This exercise allows free hand practice of continuous or interrupted suturing, using the skills acquired through tasks 1-5.
Continuous stitch – A series of stitches performed with one thread along a suture line.
Interrupted stitch – A series of single stitches tied separately along a suture line.
At the beginning of each exercise the participant chooses which will be the dominant hand and the exercise is adjusted accordingly.
Objective:
- To perform continuous/interrupted suture accurately and efficiently
- After the completion of that first phase of the program (Methodology I), data collection will follow. Data collection includes the general demographic characteristics, specifically:
- Participant name, contact information (phone number, residential address, email address), gender, age. Additionally, years of specialization, current surgical specialty, dominant hand, engaging in video games and avocation with musical instruments.
Performance data
Data that will be recorded and evaluated: Time parameters, security parameters, precision/accuracy parameters, needle loading parameters, needle pass parameters, stitch parameters.
Main list:
- Total time (sec).
- Total needle loading time (sec).
- Percentage of passes where the needle was at 90 ° (±20° deviation) relative to the suture line (%).
- Percentage of passes in which the needle entered the tissue at an angle of 60° to 90° relative to the tissue surface (%).
- Accuracy rating – accurate needle passage through entry and exit dots (%).
- Average distance between the marked points and the points through which the needle passed (mm).
- Average tension exerted on the tissue during the passage of the needle.
- Overall non-smooth management of the web.
- Number of completed sub-exercises (n).