Development of a virtual reality training curriculum for laparoscopic cholecystectomy

An ex vivo liver training model continuously perfused to simulate bleeding for suture skills involved in laparoscopic liver resection: development and validity

BACKGROUND

Suture skills are essential to laparoscopic liver resection. The current suture training models are not ideal enough. The aim of this study is to develop and verify a highly simulated-bleeding continuously perfused training model (CPTM) and to evaluate its training efficacy.

METHODS

CPTM was constructed using fresh lamb liver whose portal veins were perfused with red-dyed liquid gelatin. Construct validity of CPTMs was tested in 33 participants with three levels of laparoscopic experience (experts, intermediates, and novices) who were demanded to finish one superficial stitch and one deep stitch for suture hemostasis on CPTMs. The CPTMs were also evaluated by the experts. CPTMs were compared with dry box training models (DBTMs) regarding training efficacy among the novices who were assigned to DBTM and CPTM groups to, respectively, complete a 10-day training on CPTMs or DBTMs. Before and after their assignments, their superficial stitches were assessed by completion time, suture accuracy, and suture knot performance while their deep stitches by completion time and bleeding control.

RESULTS

CPTM proved to be construct valid by both superficial and deep stitches. Significant differences were found regarding completion time (763, 271, 174 s), suture accuracy (4.4, 1.8, 0.2 mm), and suturing knot performance (12.1, 21.5, 22.0) for superficial stitches (p < 0.001), as well as regarding completion time (807, 423, 277 s) for deep stitches (p < 0.001). Positive comments were given by all experts. CPTMs helped novices to acquire laparoscopic suture skills. Their training efficacy was significantly better than that of DBTMs (p < 0.05). Learning curves of CPTM group plateaued at the sixth round for superficial stitches and at the seventh round for deep stitches.

CONCLUSION

CPTM offers trainees a highly simulated-bleeding means to acquire advanced laparoscopic suture skills. The suture skills learned on CPTMs may improve significantly at the seventh round.

Development, Organisation and Implementation of a Surgical Skills 'Boot Camp': SIMweek

BACKGROUND

There is evidence of increased mortality and reduced efficiency in hospitals due to the annual changeover of junior doctors. This paper describes a framework to develop an intensive simulated week that will recreate experiences and situations that junixor surgical interns will likely face in their first weeks after graduation.

METHODS

To provide evidence-based recommendations, a systematic review of published literature using the keywords 'surg*', 'boot', 'camp' was performed. Reports of the development, implementation or evaluation of a simulated skills course or 'boot camp' to prepare incoming surgical interns were analysed.

RESULTS

Eighteen relevant articles were identified. Subjects on internship preparation courses have identified 'hands-on' training sessions to be very useful. In particular, mock pages have been identified as being valuable and didactic lectures have been identified as the weakest parts of the course. We first consider the end-users of the course and their associated learning needs. We subsequently discuss resources required and propose a strategy for the organisation of a course and selection of teaching faculty. Finally, we consider the costs involved in running a course.

CONCLUSIONS

This paper proposes a framework for the development, organisation and implementation of an intensive simulation course to prepare graduating medical students for their role as junior surgical intern. Facilitating the step change in responsibility from student to surgical intern may improve patient safety in addition to reducing the associated anxiety for the clinician.

Lifelike Vascular Reperfusion of a Thiel-Embalmed Pig Model and Evaluation as a Surgical Training Tool

BACKGROUND

Vascular reperfusion of Thiel cadavers can aid surgical and anatomical instruction. This study investigated whether ideal embalming circumstances provide lifelike vascular flow, enabling surgical practice and enhancing anatomical reality.

METHODS

Pressure-controlled pump-driven administration of blue embalming solution was assessed directly postmortem in a pig model (n = 4). Investigation of subsequent pump-driven vascular injection of red paraffinum perliquidum (PP) included assessment of flow parameters, intracorporeal distribution, anatomical alterations, and feasibility for surgical training. The microscopic distribution of PP was analyzed in pump-embalmed pig and gravity-embalmed human small intestines.

RESULTS

Embalming lasted 50-105 min, and maximum arterial pressure was 65 mm Hg. During embalming, the following consecutive alterations were observed: arterial filling, organ coloration, venous perfusion, and further tissue coloration during the next weeks. Most organs were adequately preserved. PP generated low arterial pressures (<30 mm Hg) and drained through the venous cannula. Generally, realistic reperfusion and preservation of original anatomy were observed, but leakage in the pleural, abdominal, and retroperitoneal cavities occurred, and computed tomography showed edematous spleen and liver. Reduction of arterial flow rates after venous drainage is a prerequisite to prevent anatomical deformation, allowing simulation of various surgeries. In pump-embalmed pig small intestines, PP flowed from artery to vein through the capillaries without extravasation. In contrast, arterioles were blocked in gravity-embalmed human tissues.

CONCLUSIONS

In a pig model, immediate postmortem pressure-controlled pump embalming generates ideal circumstances for (micro)vascular reperfusion with PP, permitting lifelike anatomy instruction and surgical training.

Post-mortem Reperfusion of a Pig: a First Step to a New Surgical Training Model?

The purpose of this experimental study was to establish a short-term post-mortem circulation in a pig model using liquid paraffin. This study also investigated the quality of vascular perfusion in the peripheral tissues. This is the first step in the development of a new revascularized human surgical training model. This first experience was performed on the hind leg of a pig. Initial cannulation of the external iliac artery and vein was followed by connection of the arterial inflow to a heart-lung machine and using the venous outflow to flush post-mortem clots and blood. Subsequently, after connecting the venous outflow to the heart-lung machine, circulation was initiated. Circulation was established during 27 min, during which the flow was constantly 130 mL/min. A steady increase in inlet pressure was observed during the experiment, which finally reached a minimum value of 124 mmHg. Perfusion was interrupted early due to an uncontrollable fluid leak. Afterwards, the distal hind leg was incised showing an equal distribution of paraffin. A short-term revascularization was successfully re-established under excellent conditions. Although the results are promising, further experiments are necessary to eventually perform a wide range of surgical procedures on revascularized human cadavers.

Development of a PROficiency-Based StePwise Endovascular Curricular Training (PROSPECT) Program

OBJECTIVES

Focus on patient safety, work-hour limitations, and cost-effective education is putting pressure to improve curricula to acquire minimally invasive techniques during surgical training. This study aimed to design a structured training program for endovascular skills and validate its assessment methods.

DESIGN

A PROficiency-based StePwise Endovascular Curricular Training (PROSPECT) program was developed, consisting of e-learning and hands-on simulation modules, focusing on iliac and superficial femoral artery atherosclerotic disease. Construct validity was investigated. Performances were assessed using multiple-choice questionnaires, valid simulation parameters, global rating scorings, and examiner checklists. Feasibility was assessed by passage of 2 final-year medical students through this PROSPECT program.

SETTING

Ghent University Hospital, a tertiary clinical care and academic center in Belgium with general surgery residency program.

PARTICIPANTS

Senior-year medical students were recruited at Ghent University Hospital. Vascular surgeons were invited to participate during conferences and meetings if they had performed at least 100 endovascular procedures as the primary operator during the last 2 years.

RESULTS

Overall, 29 medical students and 20 vascular surgeons participated. Vascular surgeons obtained higher multiple-choice questionnaire scores (median: 24.5-22.0 vs. 15.0-12.0; p < 0.001). Students took significantly longer to treat any iliac or femoral artery stenosis (3.3-14.8 vs. 5.8-30.1min; p = 0.001-0.04), whereas in more complex cases, fluoroscopy time was significantly higher in students (8.3 vs. 21.3min; p = 0.002; 7.3 vs. 13.1min; p = 0.03). In all cases, vascular surgeons scored higher on global rating scorings (51.0-42.0 vs. 29.5-18.0; p < 0.001) and examiner checklist (81.5-75.0 vs. 54.5-43.0; p < 0.001). Hence, proficiency levels based on median expert scores could be determined. There were 2 students who completed the program and passed for each step within a 3-month period during their internships.

CONCLUSIONS

A feasible and construct validated surgical program to train cognitive, technical, and nontechnical endovascular skills was developed. A structured, stepwise, proficiency-based valid endovascular program to train cognitive, technical, and human factor skills has been developed and proven to be feasible. A randomized controlled trial has been initiated to investigate its effect on performances in real life, patient outcomes, and cost-effectiveness.

A Randomized Controlled Trial to Assess the Effects of Competition on the Development of Laparoscopic Surgical Skills

BACKGROUND

Serious games have demonstrated efficacy in improving participation in surgical training activities, but studies have not yet demonstrated the effect of serious gaming on performance. This study investigated whether competitive training (CT) affects laparoscopic surgical performance.

METHODS

A total of 20 novices were recruited, and 18 (2 dropouts) were randomized into control or CT groups to perform 10 virtual reality laparoscopic cholecystectomies (LCs). Competitiveness of each participant was assessed. The CT group members were informed they were competing to outperform one another for a prize; performance ranking was shown before each session. The control group did not compete. Performance was assessed on time, movements, and instrument path length. Quality of performance was assessed with a global rating scale score.

RESULTS

There were no significant intergroup differences in baseline skill or measured competitiveness. Time and global rating scale score, at final LC, were not significantly different between groups; however, the CT group was significantly more dexterous than control and had significantly lower variance in number of movements and instrument path length at the final LC (p = 0.019). Contentiousness was inversely related to time in the CT group.

CONCLUSION

This was the first randomized controlled trial to investigate if CT can enhance performance in laparoscopic surgery. CT may lead to improved dexterity in laparoscopic surgery but yields otherwise similar performance to that of standard training in novices. Competition may have different effects on novices vs experienced surgeons, and subsequent research should investigate CT in experienced surgeons as well.

Thinking it through: mental rehearsal and performance on 2 types of laparoscopic cholecystectomy simulators

OBJECTIVE

Simulation-based training (SBT) in laparoscopic cholecystectomy (LCCY) provides an opportunity for junior residents to learn the procedure in a safe, nonthreatening environment. Mental rehearsal (MR) has the potential of augmenting skill acquisition. This project investigated the correlation between MR of LCCY with performance on 2 different types of simulators: a procedural task (PT) training model and virtual reality (VR) machine.

DESIGN

Prospective, quasi-experimental design with purposeful sampling. Postgraduate years (PGYs) 1 through 3 general surgical residents underwent standardized, distributed SBT in LCCY on either a PT trainer or a VR machine with group-based MR undertaken before 2 SBT sessions. Participants completed a pre-MR and post-MR session mental imagery questionnaire (MIQ) containing 8-items using a 7-point Likert-type scale. Data related to VR objective measures and PT video-based performances were also collected. Total scale mean scores were calculated for the first MR session and the second MR session and were compared using the t test. Pearson correlation analysis of MIQ scores with performance scores was determined.

SETTING

Louisiana State University Health New Orleans Health Sciences Center in New Orleans, Louisiana. This health sciences center is a tertiary care, academic state institution located in the Southeastern United States.

PARTICIPANTS

A total of 21 PGYs 1 through 3 general surgery residents participated. They were purposefully divided into the PT and VR training groups to allow for even PGY distribution. Of the 21 participants, 19 completed both training sessions (n = 10 for PT [PGY1 = 4, PGY2 = 4, PGY3 = 2] and n = 9 for VR [PGY1 = 4, PGY2 = 3, PGY3 = 2]).

RESULTS

After the Bonferroni adjustment, significant gains in the MIQ items related to confidence, visual imagery, and knowledge of the procedure were found. VR performance data demonstrated some statistically significant improvements. A significant negative correlation was present between the two-handed clip-and-cut VR task and MIQ gains.

CONCLUSIONS

Group MR in LCCY before SBT on a VR machine is related to improved performance time for the VR two-handed clip-and-cut task. MR may be a useful adjunct to SBT LCCY. Future work will look at the translation of these skills to clinical practice.

Virtual reality training versus blended learning of laparoscopic cholecystectomy: a randomized controlled trial with laparoscopic novices

This study compared virtual reality (VR) training with low cost-blended learning (BL) in a structured training program.Training of laparoscopic skills outside the operating room is mandatory to reduce operative times and risks.Laparoscopy-naïve medical students were randomized in 2 groups stratified for sex. The BL group (n = 42) used E-learning for laparoscopic cholecystectomy (LC) and practiced basic skills with box trainers. The VR group (n = 42) trained basic skills and LC on the LAP Mentor II (Simbionix, Cleveland, OH). Each group trained 3 × 4 hours followed by a knowledge test concerning LC. Blinded raters assessed the operative performance of cadaveric porcine LC using the Objective Structured Assessment of Technical Skills (OSATS). The LC was discontinued when it was not completed within 80 min. Students evaluated their training modality with questionnaires.The VR group completed the LC significantly faster and more often within 80 min than BL (45% v 21%, P = .02). The BL group scored higher than the VR group in the knowledge test (13.3 ± 1.3 vs 11.0 ± 1.7, P < 0.001). Both groups showed equal operative performance of LC in the OSATS score (49.4 ± 10.5 vs 49.7 ± 12.0, P = 0.90). Students generally liked training and felt well prepared for assisting in laparoscopic surgery. The efficiency of the training was judged higher by the VR group than by the BL group.VR and BL can both be applied for training the basics of LC. Multimodality training programs should be developed that combine the advantages of both approaches.

SAGES expert Delphi consensus: critical factors for safe surgical practice in laparoscopic cholecystectomy

BACKGROUND

Although it has been 25 years since the introduction of laparoscopy to cholecystectomy, outcomes remain largely unchanged, with rates of bile duct injury higher in the modern age than in the era of open surgery. The SAGES Safe Cholecystectomy Task Force (SCTF) initiative seeks to encourage a culture of safety in laparoscopic cholecystectomy (LC) and reduce biliary injury. An expert consensus study was conducted to identify interventions thought to be most effective in pursuit of this goal.

METHODS

An initial list of items for safer practice in LC was identified by the SCTF through a nominal group technique (NGT) process. These were put forward to 407 SAGES committee members in two-stage electronically distributed Delphi surveys. Consensus was achieved if at least 80 % of respondents ranked an item as 4 or 5 on a Likert scale of importance (1-5). Additionally, respondents ranked five top areas of importance for the following domains: training, assessment, and research.

RESULTS

Thirty-nine initial items were identified through NGT. Response rates for each Delphi round were 40.2 and 34 %, respectively. Final consensus was achieved on 15 items, the majority of which related to non-technical factors in LC. Key domains for training, assessment, and research were identified. Critical view of safety was deemed most important for overall safety, as well as training and assessment of LC. Intraoperative cholangiography was identified as an additional priority area for future research.

CONCLUSIONS

Consensus items to progress surgical practice, training, assessment, and research have been identified, to promote safe practice and improve patient outcomes in LC.

Fundamental arthroscopic skill differentiation with virtual reality simulation

PURPOSE

The purpose of this study was to investigate the use and validity of virtual reality modules as part of the educational approach to mastering arthroscopy in a safe environment by assessing the ability to distinguish between experience levels. Additionally, the study aimed to evaluate whether experts have greater ambidexterity than do novices.

METHODS

Three virtual reality modules (Swemac/Augmented Reality Systems, Linkoping, Sweden) were created to test fundamental arthroscopic skills. Thirty participants-10 experts consisting of faculty, 10 intermediate participants consisting of orthopaedic residents, and 10 novices consisting of medical students-performed each exercise. Steady and Telescope was designed to train centering and image stability. Steady and Probe was designed to train basic triangulation. Track and Moving Target was designed to train coordinated motions of arthroscope and probe. Metrics reflecting speed, accuracy, and efficiency of motion were used to measure construct validity.

RESULTS

Steady and Probe and Track a Moving Target both exhibited construct validity, with better performance by experts and intermediate participants than by novices (P < .05), whereas Steady and Telescope did not show validity. There was an overall trend toward better ambidexterity as a function of greater surgical experience, with experts consistently more proficient than novices throughout all 3 modules.

CONCLUSIONS

This study represents a new way to assess basic arthroscopy skills using virtual reality modules developed through task deconstruction. Participants with the most arthroscopic experience performed better and were more consistent than novices on all 3 virtual reality modules. Greater arthroscopic experience correlates with more symmetry of ambidextrous performance. However, further adjustment of the modules may better simulate fundamental arthroscopic skills and discriminate between experience levels.

CLINICAL RELEVANCE

Arthroscopy training is a critical element of orthopaedic surgery resident training. Developing techniques to safely and effectively train these skills is critical for patient safety and resident education.

An immersive "simulation week" enhances clinical performance of incoming surgical interns improved performance persists at 6 months follow-up

BACKGROUND

The transition from student to intern can be challenging. The "August" or "July effect" describes increased errors and reduced patient safety during this transition. The study objectives were to develop, pilot, and evaluate clinical performance after an immersive simulation course for incoming interns.

METHODS

Graduating students were recruited for a 1-week immersive simulation course. Controls received no simulation training. Primary outcome (at baseline, and 1 and 6 months) was clinical performance on Objective Structured Clinical Examinations (OSCE) of clinical procedures and surgical technical skills. Secondary outcomes were self-reported confidence and clinical procedure logbook data.

RESULTS

Nineteen students were recruited. Sixteen completed the 6-month follow-up, 10 in the intervention group and 6 in the control group. No differences were demonstrated between interventions and controls at baseline (OSCE [median, 66 vs. 78; P = .181], technical skills [48 vs. 52.5; P = .381], and confidence [101 vs 96; P = .368]). Interventions outperformed controls at 1 month (OSCE [111 vs 82; P = .001], technical skills [78.5 vs 63; P = .030], and confidence [142 vs. 119; P < .001]), and 6 months (OSCE [107 vs. 93; P = .007], technical skills [92.5 vs. 69; P = .044], and confidence [148 vs. 129; P = .022]). No differences were observed in numbers of clinical procedures performed at 1 (P = .958), 4 (P = .093), or 6 months (P = .713).

CONCLUSION

The immersive simulation course objectively improved subjects' clinical skills, technical skills, and confidence. Despite similar clinical experience as controls, the intervention group's improved performance persisted at 6 months follow-up. This feasible and effective intervention to ease transition from student to intern could reduce errors and enhance patient safety.

A PC-based laparoscopic surgery skills training and assessment system

The purpose of this study is to build a cost-effective and easy-to-popularize laparoscopic training system based on improving traditional training box. The system has the capability of objective skills assessment and the function of automatic recording of training process and results, as well as 3-dimensional coordinate tracking of instruments. The results of pilot experiment in laparoscopic-assisted grip skill assessment had been shown the system can assess the different grip ability level between the senior surgeons and junior residents. Regarding to the evaluation of training effectiveness, five subjects without laparoscopic surgery experiences were asked to perform grip training for five days to observe their training curves. According to the experimental results, the total time taken for subject 1 to subject 5 are improved by 54.9%, 52.0%, 60.6%, 23.3%, and 63.5% separately.

Deliberate practice enhances quality of laparoscopic surgical performance in a randomized controlled trial: from arrested development to expert performance

BACKGROUND

This study investigated whether deliberate practice leads to an increase in surgical quality in virtual reality (VR) laparoscopic cholecystectomies (LC). Previous research has suggested that sustained DP is effective in surgical training.

METHODS

Fourteen residents were randomized into deliberate practice (n = 7) or control training (n = 7). Both groups performed ten sessions of two VR LCs. Each session, the DP group was assigned 30 min of DP activities in between LCs while the control group viewed educational videos or read journal articles. Performance was assessed on speed and dexterity; quality was rated with global (GRS) and procedure-specific (PSRS) rating scales. All participants then performed five porcine LCs.

RESULTS

Both groups improved over 20 VR LCs in time, dexterity, and global rating scales (all p < 0.05). After 20 LCs, there were no differences in speed or dexterity between groups. The DP group achieved higher quality of VR surgical performance than control for GRS (26 vs. 20, p = 0.001) and PSRS (18 vs. 15, p = 0.001). For VR cases, DP subjects plateaued at GRS = 25 after ten cases and control group at GRS = 20 after five cases. At completion of VR training, 100 % of the DP group reached target quality of performance (GRS ≥ 21) compared with 30 % in the control group. There were no significant differences for improvements in time or dexterity over five porcine LCs.

CONCLUSION

This study suggests that DP leads to higher quality performance in VR LC than standard training alone. Standard training may leave individuals in a state of "arrested development" compared with DP.

Volume Preserved Mass-Spring Model with Novel Constraints for Soft Tissue Deformation

An interactive surgical simulation system needs to meet three main requirements, speed, accuracy, and stability. In this paper, we present a stable and accurate method for animating mass-spring systems in real time. An integration scheme derived from explicit integration is used to obtain interactive realistic animation for a multiobject environment. We explore a predictor-corrector approach by correcting the estimation of the explicit integration in a poststep process. We introduce novel constraints on positions into the mass-spring model (MSM) to model the nonlinearity and preserve volume for the realistic simulation of the incompressibility. We verify the proposed MSM by comparing its deformations with the reference deformations of the nonlinear finite-element method. Moreover, experiments on porcine organs are designed for the evaluation of the multiobject deformation. Using a pair of freshly harvested porcine liver and gallbladder, the real organ deformations are acquired by computed tomography and used as the reference ground truth. Compared to the porcine model, our model achieves a 1.502 mm mean absolute error measured at landmark locations for cases with small deformation (the largest deformation is 49.109 mm) and a 3.639 mm mean absolute error for cases with large deformation (the largest deformation is 83.137 mm). The changes of volume for the two deformations are limited to 0.030% and 0.057%, respectively. Finally, an implementation in a virtual reality environment for laparoscopic cholecystectomy demonstrates that our model is capable to simulate large deformation and preserve volume in real-time calculations.

Surgical team composition differs between laparoscopic and open procedures

BACKGROUND

Performing laparoscopic procedures requires different skill sets and team dynamics compared with open procedures. We evaluated team composition and procedure time between these two surgical approaches using data collected from hospitals in the United State and Canada.

METHODS

A total of 1,260 general surgical cases were reviewed retrospectively, recording the number of operation personnel, procedure complexity, and the procedure time.

RESULTS

Laparoscopic procedures (n = 930), on average, had a higher procedure difficulty coding which led to a longer procedure time and involved more people in the surgical team than open procedures (n = 330). When we selected cases with matched procedure difficulty coding, laparoscopic procedures (n = 450) still required longer procedure times and involved more operative personnel than open procedures (n = 92).

DISCUSSION

Increased laparoscopic team size and procedure time must be influenced by factors other than case difficulty. The factors may derive from inherent complexity of the surgical setting and team dynamics unique to laparoscopic procedures.

Assessment of procedural skills using virtual simulation remains a challenge

OBJECTIVE

The LAP Mentor is a procedural simulator that provides a stepwise training for laparoscopic cholecystectomy. This study addresses its "construct" validity that is present when a simulator is able to discriminate between persons with known differences in performance level on the laparoscopic cholecystectomy in real life.

DESIGN

Three groups with different skill levels performed 2 trials of 4 distinct parts of the cholecystectomy procedure (cholecystectomy exercises) and 1 full procedure on the LAP Mentor. Assessment parameters concerning the quantity and the quality of performance were compared between groups using the Kruskal-Wallis and Mann-Whitney U tests.

SETTING

The entire research was performed in the Center for Surgical Technologies, Leuven, Belgium.

PARTICIPANTS

For study purposes, 5 expert abdominal laparoscopists (>100 laparoscopic cholecystectomies performed), 11 surgical residents (10-30 cholecystectomies performed), and 10 novices (minimal laparoscopic experience) were recruited.

RESULTS

With regard to the quantity of performance (time needed and number of movements), the experts showed significantly better results compared with the novices in the cholecystectomy exercises. Only in the full procedure, the results of all the parameters (except speed) were significantly different between the 3 groups, with the best results observed for the experts and worst for the novices. With respect to quality of performance, only the parameter "accuracy rate of dissection" in exercise 3 showed significantly better performance by the experts.

CONCLUSIONS

Only the full procedure of the LAP Mentor procedural simulator has enough discriminative power to claim construct validity. However, the lack of quality control, which is indispensible in the evaluation of procedural skills, makes it currently unsuited for the assessment of procedural laparoscopic skills. The role of the simulator in a training context remains to be elucidated.

Hand gesture guided robot-assisted surgery based on a direct augmented reality interface

Radiofrequency (RF) ablation is a good alternative to hepatic resection for treatment of liver tumors. However, accurate needle insertion requires precise hand-eye coordination and is also affected by the difficulty of RF needle navigation. This paper proposes a cooperative surgical robot system, guided by hand gestures and supported by an augmented reality (AR)-based surgical field, for robot-assisted percutaneous treatment. It establishes a robot-assisted natural AR guidance mechanism that incorporates the advantages of the following three aspects: AR visual guidance information, surgeon's experiences and accuracy of robotic surgery. A projector-based AR environment is directly overlaid on a patient to display preoperative and intraoperative information, while a mobile surgical robot system implements specified RF needle insertion plans. Natural hand gestures are used as an intuitive and robust method to interact with both the AR system and surgical robot. The proposed system was evaluated on a mannequin model. Experimental results demonstrated that hand gesture guidance was able to effectively guide the surgical robot, and the robot-assisted implementation was found to improve the accuracy of needle insertion. This human-robot cooperative mechanism is a promising approach for precise transcutaneous ablation therapy.

Assessing Performance in Shoulder Arthroscopy: The Imperial Global Arthroscopy Rating Scale (IGARS)

BACKGROUND

Surgical training is undergoing major changes with reduced resident work hours and an increasing focus on patient safety and surgical aptitude. The aim of this study was to create a valid, reliable method for an assessment of arthroscopic skills that is independent of time and place and is designed for both real and simulated settings. The validity of the scale was tested using a virtual reality shoulder arthroscopy simulator.

METHODS

The study consisted of two parts. In the first part, an Imperial Global Arthroscopy Rating Scale for assessing technical performance was developed using a Delphi method. Application of this scale required installing a dual-camera system to synchronously record the simulator screen and body movements of trainees to allow an assessment that is independent of time and place. The scale includes aspects such as efficient portal positioning, angles of instrument insertion, proficiency in handling the arthroscope and adequately manipulating the camera, and triangulation skills. In the second part of the study, a validation study was conducted. Two experienced arthroscopic surgeons, blinded to the identities and experience of the participants, each assessed forty-nine subjects performing three different tests using the Imperial Global Arthroscopy Rating Scale. Results were analyzed using two-way analysis of variance with measures of absolute agreement. The intraclass correlation coefficient was calculated for each test to assess inter-rater reliability.

RESULTS

The scale demonstrated high internal consistency (Cronbach alpha, 0.918). The intraclass correlation coefficient demonstrated high agreement between the assessors: 0.91 (p < 0.001). Construct validity was evaluated using Kruskal-Wallis one-way analysis of variance (chi-square test, 29.826; p < 0.001), demonstrating that the Imperial Global Arthroscopy Rating Scale distinguishes significantly between subjects with different levels of experience utilizing a virtual reality simulator.

CONCLUSIONS

The Imperial Global Arthroscopy Rating Scale has a high internal consistency and excellent inter-rater reliability and offers an approach for assessing technical performance in basic arthroscopy on a virtual reality simulator.

CLINICAL RELEVANCE

The Imperial Global Arthroscopy Rating Scale provides detailed information on surgical skills. Although it requires further validation in the operating room, this scale, which is independent of time and place, offers a robust and reliable method for assessing arthroscopic technical skills.

Simulation and its role in training

Despite its short history, surgical simulation has been successfully introduced into surgical residency programs in an effort to augment training. A wide range of simulator types and levels of complexity have proven an effective teaching method for surgical trainees. They have been used for training in areas such as general surgery, urology, gynecology, and ophthalmology among others. Coincident with the introduction of simulators is the need for objective evaluation of skills learned on them, which has led to the development and validation of multiple evaluation tools. This article evaluates the drivers for simulation, types of simulators, training, and evaluation of them especially as it pertains to laparoscopic colorectal surgery.

Advanced training in laparoscopic abdominal surgery: a systematic review

BACKGROUND

Simulation has spread widely this last decade, especially in laparoscopic surgery, and training out of the operating room has proven its positive impact on basic skills during real laparoscopic procedures. Few articles dealing with advanced training in laparoscopic abdominal surgery, however, have been published. Such training may decrease learning curves in the operating room for junior surgeons with limited access to complex laparoscopic procedures as a primary operator.

METHODS

Two reviewers, using MEDLINE, EMBASE, and The Cochrane Library conducted a systematic research with combinations of the following keywords: (teaching OR education OR computer simulation) AND laparoscopy AND (gastric OR stomach OR colorectal OR colon OR rectum OR small bowel OR liver OR spleen OR pancreas OR advanced surgery OR advanced procedure OR complex procedure). Additional studies were searched in the reference lists of all included articles.

RESULTS

Fifty-four original studies were retrieved. Their level of evidence was low: most of the studies were case series and one fifth were purely descriptive, but there were eight randomized trials. Pig models and video trainers as well as gastric and colorectal procedures were mainly assessed. The retrieved studies showed some encouraging trends in terms of trainee satisfaction with improvement after training, but the improvements were mainly on the training tool itself. Some tools have been proven to be construct-valid.

CONCLUSION

Higher-quality studies are required to appraise educational value in this field.

Clinical application of navigation surgery using augmented reality in the abdominal field

This article presents general principles and recent advancements in the clinical application of augmented reality-based navigation surgery (AR based NS) for abdominal procedures and includes a description of our clinical trial and subsequent outcomes. Moreover, current problems and future aspects are discussed. The development of AR-based NS in the abdomen is delayed compared with another field because of the problem of intraoperative organ deformations or the existence of established modalities. Although there are a few reports on the clinical use of AR-based NS for digestive surgery, sophisticated technologies in urology have often been reported. However, the rapid widespread use of video- or robot assisted surgeries requires this technology. We have worked to develop a system of AR-based NS for hepatobiliary and pancreatic surgery. Then we developed a short rigid scope that enables surgeons to obtain 3D view. We recently focused on pancreatic surgery, because intraoperative organ shifting is minimal. The position of each organ in overlaid image almost corresponded with that of the actual organ with about 5 mm of mean registration errors. Intraoperative information generated from this system provided us with useful navigation. However, AR-based NS has several problems to overcome such as organ deformity, evaluation of utility, portability or cost.

Visual control strategies of surgeons: a novel method of establishing the construct validity of a transurethral resection of the prostate surgical simulator

OBJECTIVE

To examine novice and expert differences in visual control strategies while performing a virtual reality transurethral resection of the prostate (TURP) task and to determine if these differences could provide a novel method for assessing construct validity of the simulator.

SUBJECTS AND METHODS

A total of 11 novices (no TURP experience) and 7 experts (>200 TURPs) completed a virtual reality prostate resection task on the TURPsim (Simbionix USA Corp, Cleveland, OH) while wearing an eye tracker (ASL, Bedford, MA). Performance parameters and the surgeon's visual control strategy were measured and compared between the 2 groups.

RESULTS

Experts resected a greater percentage of prostate than novices (p < 0.01) and had less active diathermy time without tissue contact (p < 0.01). Experts adopted a target-locking visual strategy, employing fewer visual fixations (p < 0.05) with longer mean fixation duration (p < 0.005). With multiple learning trials, novices' performance improved and the adoption of a more expertlike gaze strategy was observed.

CONCLUSION

Significant differences between experts and novices in both performance and visual control strategy were observed. The study of visual control strategies may be a useful adjunct, alongside measurements of motor performance, providing a novel method of assessing the construct validity of surgical simulators.

Individualized deliberate practice on a virtual reality simulator improves technical performance of surgical novices in the operating room: a randomized controlled trial

OBJECTIVE

The purpose of this study was to investigate whether individualized deliberate practice on a virtual reality (VR) simulator results in improved technical performance in the operating room.

BACKGROUND

Training on VR simulators has been shown to improve technical performance in the operating room (OR). Currently described VR curricula consist of trainees practicing the same tasks until expert proficiency is reached. It has yet to be investigated whether the individualized deliberate practice, where curricula tasks vary depending on prior levels of technical proficiency, would translate into the OR.

METHODS

This single-blinded prospective trial randomized 16 novice surgical residents to a deliberate practice (DP) group and a conventional residency training group. Both groups performed a laparoscopic cholecystectomy in the OR that was video-recorded. Technical performance of DP group residents in the OR was assessed using 3 validated assessment tools. A score of less than 60% on any component of the assessment tool resulted in the trainee practicing a specific task on the VR simulator. The DP group practiced on the simulator as per their individualized schedule. Both groups then performed another laparoscopic cholecystectomy. A blinded expert assessed the OR recordings using a validated global rating scale.

RESULTS

Although both groups had similar technical abilities preintervention [DP: median score, 13.5 (9.3-15.0); control: median score, 14.5 (9.3-17.8); P = 0.45], the DP residents had a superior technical performance postintervention [DP: median score, 17.0 (15.3-18.5); control: median score, 12.5 (7.5-14.0); P = 0.03]. Of 8 DP residents, 6 practiced 5 basic VR tasks (median 1 trial to pass), and 7 of 8 practiced 2 advanced tasks (median 4 trials to pass).

CONCLUSIONS

A curriculum of deliberate individualized practice on a VR simulator improves technical performance in the OR. This has implications to greatly improve the feasibility of implementing simulation-based curricula in residency training programs, rather then having them being limited to research protocols.

Evaluation of procedural learning transfer from a virtual environment to a real situation: a case study on tank maintenance training

Virtual reality opens new opportunities for operator training in complex tasks. It lowers costs and has fewer constraints than traditional training. The ultimate goal of virtual training is to transfer knowledge gained in a virtual environment to an actual real-world setting. This study tested whether a maintenance procedure could be learnt equally well by virtual-environment and conventional training. Forty-two adults were divided into three equally sized groups: virtual training (GVT® [generic virtual training]), conventional training (using a real tank suspension and preparation station) and control (no training). Participants then performed the procedure individually in the real environment. Both training types (conventional and virtual) produced similar levels of performance when the procedure was carried out in real conditions. Performance level for the two trained groups was better in terms of success and time taken to complete the task, time spent consulting job instructions and number of times the instructor provided guidance.

Postmortem pump-driven reperfusion of the vascular system of porcine lungs: towards a new model for surgical training

PURPOSE

The objective of this experiment is to establish a continuous postmortem circulation in the vascular system of porcine lungs and to evaluate the pulmonary distribution of the perfusate. This research is performed in the bigger scope of a revascularization project of Thiel embalmed specimens. This technique enables teaching anatomy, practicing surgical procedures and doing research under lifelike circumstances.

METHODS

After cannulation of the pulmonary trunk and the left atrium, the vascular system was flushed with paraffinum perliquidum (PP) through a heart-lung machine. A continuous circulation was then established using red PP, during which perfusion parameters were measured. The distribution of contrast-containing PP in the pulmonary circulation was visualized on computed tomography. Finally, the amount of leak from the vascular system was calculated.

RESULTS

A reperfusion of the vascular system was initiated for 37 min. The flow rate ranged between 80 and 130 ml/min throughout the experiment with acceptable perfusion pressures (range: 37-78 mm Hg). Computed tomography imaging and 3D reconstruction revealed a diffuse vascular distribution of PP and a decreasing vascularization ratio in cranial direction. A self-limiting leak (i.e. 66.8% of the circulating volume) towards the tracheobronchial tree due to vessel rupture was also measured.

CONCLUSIONS

PP enables circulation in an isolated porcine lung model with an acceptable pressure-flow relationship resulting in an excellent recruitment of the vascular system. Despite these promising results, rupture of vessel walls may cause leaks. Further exploration of the perfusion capacities of PP in other organs is necessary. Eventually, this could lead to the development of reperfused Thiel embalmed human bodies, which have several applications.

Development of a knowledge, skills, and attitudes framework for training in laparoscopic cholecystectomy

BACKGROUND

The implementation of duty-hour restrictions and a heightened awareness of patient safety has changed resident education and training. A new focus has been placed on high-yield training programs and simulation training has naturally grown to fill this need.

METHODS

This article discusses the development of a training framework, knowledge, skills, and attitudes, and the design of a surgical simulation curriculum. Five residents were recruited for a pilot study of the curriculum.

RESULTS

A successful framework for curriculum development was implemented using laparoscopic cholecystectomy as the example. The curriculum consisted of classroom and virtual reality simulation training and was completed in 3.1 to 4.8 hours.

CONCLUSIONS

The current curricula that have been developed for surgical education cover the breadth of a surgical residency well. This curriculum went beyond these curricula and developed a structured framework for surgical training, a method that can be applied to any procedure.

A prospective randomized controlled blinded study to evaluate the effect of short-term focused training program in laparoscopy on operating room performance of surgery residents (CTRI /2012/11/003113)

INTRODUCTION

Laparoscopic surgery requires certain specific skills. There have been several attempts to minimize the learning curve with training outside the operation room. Although simulators have been well validated as tools to teach technical skills, their integration into comprehensive curricula is lacking. Several randomized controlled trials and systematic reviews have demonstrated that the technical skills learned on these simulators transfer to the operating room. Currently, however, the integration of these simulated models into formal residency training curricula is lacking. In our institute, we have adopted the Tuebingen Trainer devised by Professor GF Buess from Germany. The purpose of this study was to evaluate the training of surgical residents on an ex vivo phantom model for basic laparoscopic skill acquisition and its transferability to the OR performance.

MATERIALS AND METHODS

Seventeen general surgery residents were randomized into 2 groups: Laparoscopic Training Group (n = 9, Group A) and Standard Training Group (n = 8, Group B). Group A underwent training in the Minimally Invasive Surgery Training Centre on the porcine phantom model and did 10 laparoscopic cholecystectomies, whereas Group B did not undergo training in the Minimally Invasive Surgery Training Centre. All the participants performed a laparoscopic cholecystectomy in the operation theater in the presence of a consultant who was blinded to the training status of the participants. The performance of the residents in both groups in the operation theater was assessed using GOALS criteria, surgical performance assessment parameters, task-specific checklists, and visual analog scale for gallbladder perforation difficulty and overall competence.

RESULTS

The Laparoscopic Training Group had better performance than the Standard Training Group regarding operation time, GOALS criteria, and Task-specific checklists. Although the surgical performance assessments, i.e. cystic duct and artery identification scores, gallbladder perforation scores, and liver injury scores, were better in the Laparoscopic Training Groups, they were not statistically significant. The overall difficulty of the surgery was comparable in both the groups. The Laparoscopic Training Group exhibited significant overall competence on visual analog scale scores.

CONCLUSION

Our study has clearly shown that training on the Tuebingen Trainer with integrated porcine organs results in a statistically significant improvement in the operating room performance of surgical residents as compared with the nontrained residents, thereby indicating a transfer of skills from training to the operating room.

Survey-based analysis of fundamental tasks for effective use of electrosurgical instruments

BACKGROUND

Despite widespread use of electrosurgical instruments, there are no widely accepted tasks for training and evaluation of technical skills. The purpose of this study is to propose a set of tasks and report experts' evaluations of the proposed tasks for validity, technical skills versus knowledge requirements, and utility for future privileging curricula.

METHODS

A set of seven hands-on tasks involving electrical energy were identified based on the fundamental use of surgical energy (FUSE) curriculum of the Society of American Gastrointestinal and Endoscopic Surgeons. A web-based survey was developed based on the seven identified tasks, with seven questions asked for each task. These questions rated candidate tasks on their suitability for validation studies, the role of manual skills, and the appropriateness of including the task in privileging curricula. Members of the FUSE committee were sent the web-based survey, and responses were recorded.

RESULTS

Of the 27 members of the FUSE committee, 16 responded to the survey. A total of 775 Likert-style responses were recorded and quantified to a 1-5 range. Overall, responses within task-question pairs had a mean standard deviation of 0.83, suggesting general agreement. Tasks requiring bi-manual dexterity scored higher than single-handed tasks on a combined, four-question Likert-scale index for task validation (p < 0.0001), and a two-question index for manual skills (p < 0.0001).

CONCLUSIONS

Survey responses indicated general agreement that the identified tasks represent important technical skills and are consistent with actions in the operating room. Bimanual tasks were favored for validation purposes over single-handed tasks. The traction and monopolar dissection and monopolar coaptation tasks had the highest agreement with validation-oriented questions (97 and 87 %, respectively).

Randomized controlled trial on the effect of coaching in simulated laparoscopic training

BACKGROUND

The effect of coaching on surgical quality and understanding in simulated training remains unknown. The aim of this study was compare the effects of structured coaching and autodidactic training in simulated laparoscopic surgery.

METHODS

Seventeen surgically naive medical students were randomized into two groups: eight were placed into an intervention group and received structured coaching, and nine were placed into a control group and received no training. They each performed 10 laparoscopic cholecystectomies on a virtual reality simulator. The surgical quality of the first, fifth, and 10th operations was evaluated by 2 independent blinded assessors using the Competency Assessment Tool (CAT) for cholecystectomy. Understanding of operative strategy was tested before the first, fifth, and 10th operation. Performance metrics, path length, total number of movements, operating time, and error frequency were evaluated. The groups were compared by the Mann-Whitney U test. Proficiency gain curves were plotted using curve fit and CUSUM models; change point analysis was performed by multiple Wilcoxon signed rank analyses.

RESULTS

The intervention group scored significantly higher on the CAT assessment of procedures 1, 5, and 10, with increasing disparity. They also performed better in the knowledge test at procedures 5 and 10, again with an increasing difference. The learning curve for error frequency of the intervention group reached competency after operation 7, whereas the control group did not plateau by procedure 10. The learning curves of both groups for path length and number movements were almost identical; the mean operation time was shorter for the control group.

CONCLUSIONS

Clinically relevant markers of proficiency including error reduction, understanding of surgical strategy, and surgical quality are significantly improved with structured coaching. Path length and number of movements representing merely manual skills are developed with task repetition rather than influenced by coaching. Structured coaching may represent a key component in the acquisition of procedural skills.

Learning curves for urological procedures: a systematic review

OBJECTIVE

To determine the number of cases a urological surgeon must complete to achieve proficiency for various urological procedures.

PATIENT AND METHODS

The MEDLINE, EMBASE and PsycINFO databases were systematically searched for studies published up to December 2011. Studies pertaining to learning curves of urological procedures were included. Two reviewers independently identified potentially relevant articles. Procedure name, statistical analysis, procedure setting, number of participants, outcomes and learning curves were analysed.

RESULTS

Forty-four studies described the learning curve for different urological procedures. The learning curve for open radical prostatectomy ranged from 250 to 1000 cases and for laparoscopic radical prostatectomy from 200 to 750 cases. The learning curve for robot-assisted laparoscopic prostatectomy (RALP) has been reported to be 40 procedures as a minimum number. Robot-assisted radical cystectomy has a documented learning curve of 16-30 cases, depending on which outcome variable is measured. Irrespective of previous laparoscopic experience, there is a significant reduction in operating time (P = 0.008), estimated blood loss (P = 0.008) and complication rates (P = 0.042) after 100 RALPs.

CONCLUSIONS

The available literature can act as a guide to the learning curves of trainee urologists. Although the learning curve may vary among individual surgeons, a consensus should exist for the minimum number of cases to achieve proficiency. The complexities associated with defining procedural competence are vast. The majority of learning curve trials have focused on the latest surgical techniques and there is a paucity of data pertaining to basic urological procedures.

Virtual reality does not meet expectations in a pilot study on multimodal laparoscopic surgery training

BACKGROUND

The purpose of the present study was to determine the value of virtual reality (VR) training for a multimodality training program of basic laparoscopic surgery.

MATERIALS AND METHODS

Participants in a two-day multimodality training for laparoscopic surgery used box trainers, live animal training, and cadaveric training on the pulsating organ perfusion (POP) trainer in a structured and standardized training program. The participants were divided into two groups. The VR group (n = 13) also practiced with VR training during the program, whereas the control group (n = 14) did not use VR training. The training modalities were assessed using questionnaires with a five-point Likert scale after the program. Concerning VR training, members of the control group assessed their expectations, whereas the VR group assessed the actual experience of using it. Skills performance was evaluated with five standardized test tasks in a live porcine model before (pre-test) and after (post-test) the training program. Laparoscopic skills were measured by task completion time and a general performance score for each task. Baseline tests were compared with laparoscopic experience of all participants for construct validity of the skills test.

RESULTS

The expected benefit from VR training of the control group was higher than the experienced benefit of the VR group. Box and POP training received better ratings from the VR group than from the control group for some purposes. Both groups improved their skill parameters significantly from pre-training to post-training tests [score +17 % (P < 0.01), time -29 % (P < 0.01)]. No significant difference was found between the two groups for laparoscopic skills improvement except for the score in the instrument coordination task. Construct validity of the skills test was significant for both time and score.

CONCLUSIONS

At its current level of performance, VR training does not meet expectations. No additional benefit was observed from VR training in our multimodality training program.

Toward technology-supported surgical training: the potential of virtual simulators in laparoscopic surgery

BACKGROUND AND AIMS

The mastery of manual skills that are indispensable for the performance of surgical tasks is a competence specific to surgery. One way of facilitating this acquisition is to move the training out of the operating room and all of its restrictions. Surgical training out of the operating room, also called simulation, has spread widely in the past decade, especially in laparoscopic and endoscopic surgery.

MATERIAL AND METHODS

This review assesses the role of virtual reality (VR) simulators in laparoscopic surgery and their actual impact on technical skills.

RESULTS AND CONCLUSIONS

There is a wealth of simulators, ranging from low- to high-fidelity simulators incorporating haptic feedback. They comprise basic tasks, procedural modules, and full procedures. Virtual reality simulators have shown acceptable fidelity and validity evidence. Moreover, training out of the operating room on virtual reality simulators has demonstrated its positive impact on basic skills during real laparoscopic procedures in patients. The benefit of virtual reality over simple video trainers remains unclear for teaching basic skills. However, virtual reality simulators provide automatic feedback that permitted to design structured competency-based curricula and allow deliberate practice. Finally, advanced procedures and patient-specific models have been designed on virtual reality simulators, and further investigations are still awaited to appraise their educational value.

A newly designed portable ergonomic laparoscopic skills Ergo-Lap simulator

OBJECTIVE

The cost of laparoscopic simulators restricts the wide use of simulation for training of basic psychomotor skills. This paper describes the scientifically-based development of an inexpensive and portable Ergonomic Laparoscopic Skills (Ergo-Lap) simulator with multiple tasks.

MATERIAL AND METHODS

The design of this Ergo-Lap simulator and related training task panel was based on scientific research regarding the representative skills and the ergonomic guidelines for laparoscopic surgery. A user-centred design approach was followed. Fifty-three surgical participants with variable laparoscopic experience (14 medical students, 27 surgeons in training, and 12 experienced laparoscopic surgeons) performed several tasks on the prototype and gave their feedback by filling out a 5-point scale Likert scale questionnaire.

RESULTS

The results of the usability evaluation showed that the participants regarded the Ergo-Lap simulator as a useful device to practice the basic and advanced skills effectively. Forty-three of the 53 participants indicated they would like to purchase this simulator since it is easy to use and challenges their laparoscopic skills.

CONCLUSIONS

For laparoscopic skills training, this inexpensive Ergo-Lap simulator with diverse task choices offers a simple training opportunity for trainees who want to practice laparoscopic skills at home or at the office.