Development and evaluation of a trauma decision-making simulator in Oculus virtual reality

Background

Consumer-available virtual-reality technology was launched in 2016 with strong foundations in the entertainment-industry. We developed an innovative medical-training simulator on the Oculus? Gear-VR platform. This novel application was developed utilising internationally recognised Advanced Trauma Life Support (ATLS) principles, requiring decision-making skills for critically-injured virtual-patients.

Initial validation of a virtual-reality robotic simulator

Robotic surgery is an accepted adjunct to minimally invasive surgery, but training is restricted to console time. Virtual-reality (VR) simulation has been shown to be effective for laparoscopic training and so we seek to validate a novel VR robotic simulator. The American Urological Association (AUA) Office of Education approved this study. Subjects enrolled in a robotics training course at the 2007 AUA annual meeting underwent skills training in a da Vinci dry-lab module and a virtual-reality robotics module which included a three-dimensional (3D) VR robotic simulator. Demographic and acceptability data were obtained, and performance metrics from the simulator were compared between experienced and nonexperienced roboticists for a ring transfer task. Fifteen subjects—four with previous robotic surgery experience and 11 without—participated. Nine subjects were still in urology training and nearly half of the group had reported playing video games. Overall performance of the da Vinci system and the simulator were deemed acceptable by a Likert scale (0–6) rating of 5.23 versus 4.69, respectively. Experienced subjects outperformed nonexperienced subjects on the simulator on three metrics: total task time (96 s versus 159 s, P < 0.02), economy of motion (1,301 mm versus 2,095 mm, P < 0.04), and time the telemanipulators spent outside of the center of the platform’s workspace (4 s versus 35 s, P < 0.02). This is the first demonstration of face and construct validity of a virtual-reality robotic simulator. Further studies assessing predictive validity are ultimately required to support incorporation of VR robotic simulation into training curricula.     

Virtual reality and computer-enhanced training devices equally improve laparoscopic surgical skill in novices

BACKGROUND: The study aim was to compare the effectiveness of virtual reality and computer-enhanced videoscopic training devices for training novice surgeons in complex laparoscopic skills. METHODS: Third-year medical students received instruction on laparoscopic intracorporeal suturing and knot tying and then underwent a pretraining assessment of the task using a live porcine model. Students were then randomized to objectives-based training on either the virtual reality (n=8) or computer-enhanced (n=8) training devices for 4 weeks, after which the assessment was repeated. RESULTS: Posttraining performance had improved compared with pretraining performance in both task completion rate (94% versus 18%; P<0.001*) and time [181+/-58 (SD) versus 292+/-24*]. Performance of the 2 groups was comparable before and after training. Of the subjects, 88% thought that haptic cues were important in simulators. Both groups agreed that their respective training systems were effective teaching tools, but computer-enhanced device trainees were more likely to rate their training as representative of reality (P<0.01). CONCLUSIONS: Training on virtual reality and computer-enhanced devices had equivalent effects on skills improvement in novices. Despite the perception that haptic feedback is important in laparoscopic simulation training, its absence in the virtual reality device did not impede acquisition of skill.     

An early introduction to surgical skills: Validating a low-cost laparoscopic skill training program purpose built for undergraduate medical education

BackgroundMedical student exposure to laparoscopy is limited to observation despite the prevalence of minimally invasive techniques in practice. The high cost of laparoscopic simulation equipment, commonly called “box trainers”, limits undergraduate exposure to skill training.MethodsStudents at a Midwestern medical school were recruited to participate in an experimental laparoscopic skill training program. One cohort (n = 17) used a DIY box trainer design freely available on MedEdPORTAL. A second cohort (n = 17) used a commercially available equivalent. Pre- and post-training attempts for four tasks were scored and the difference was calculated. The average differences for each cohort were then contrasted statistically.ResultsSignificant performance improvements (pre- and post-training) were demonstrated regardless of group allocation. The difference in performance between the cohorts was not significant for any task (p > 0.05).ConclusionsThis low-cost training program using DIY box trainers is as effective as commercially available equivalent box trainers for introducing laparoscopic skills to medical students.     

Challenges to the development of complex virtual reality surgical simulations

Virtual reality simulation in surgical training has become more widely used and intensely investigated in an effort to develop safer, more efficient, measurable training processes. The development of virtual reality simulation of surgical procedures has begun, but well-described technical obstacles must be overcome to permit varied training in a clinically realistic computer-generated environment. These challenges include development of realistic surgical interfaces and physical objects within the computer-generated environment, modeling of realistic interactions between objects, rendering of the surgical field, and development of signal processing for complex events associated with surgery. Of these, the realistic modeling of tissue objects that are fully responsive to surgical manipulations is the most challenging. Threats to early success include relatively limited resources for development and procurement, as well as smaller potential for return on investment than in other simulation industries that face similar problems. Despite these difficulties, steady progress continues to be made in these areas. If executed properly, virtual reality offers inherent advantages over other training systems in creating a realistic surgical environment and facilitating measurement of surgeon performance. Once developed, complex new virtual reality training devices must be validated for their usefulness in formative training and assessment of skill to be established.     

Can skills assessment on a virtual reality trainer predict a surgical trainee’s talent in laparoscopic surgery?

Background A number of studies have investigated several aspects of feasibility and validity of performance assessments with virtual reality surgical simulators. However, the validity of performance assessments is limited by the reliability of such measurements, and some issues of reliability still need to be addressed. This study aimed to evaluate the hypothesis that test subjects show logarithmic performance curves on repetitive trials for a component task of laparoscopic cholecystectomy on a virtual reality simulator, and that interindividual differences in performance after considerable training are significant. According to kinesiologic theory, logarithmic performance curves are expected and an individual’s learning capacity for a specific task can be extrapolated, allowing quantification of a person’s innate ability to develop task-specific skills. Methods In this study, 20 medical students at the University of Basel Medical School performed five trials of a standardized task on the LS 500 virtual reality simulator for laparoscopic surgery. Task completion time, number of errors, economy of instrument movements, and maximum speed of instrument movements were measured. Results The hypothesis was confirmed by the fact that the performance curves for some of the simulator measurements were very close to logarithmic curves, and there were significant interindividual differences in performance at the end of the repetitive trials. Conclusions Assessment of perceptual motor skills and the innate ability of an individual with no prior experience in laparoscopic surgery to develop such skills using the LS 500 VR surgical simulator is feasible and reliable.     

Active vs passive haptic feedback technology in virtual reality arthroscopy simulation: Which is most realistic?

BackgroundVirtual Reality (VR) simulators are playing an increasingly prominent role in orthopaedic training and education. Face-validity - the degree to which reality is accurately represented - underpins the value of a VR simulator as a learning tool for trainees. Despite the importance of tactile feedback in arthroscopy, there is a paucity for evidence regarding the role of haptics in VR arthroscopy simulator realism.PurposeTo assess the difference in face validity between two high fidelity VR simulators employing passive and active haptic feedback technology respectively.Method38 participants were recruited and divided into intermediate and expert groups based on orthopaedic training grade. Each participant completed a 12-point diagnostic knee arthroscopy VR module using the active haptic Simbionix ARTHRO Mentor and passive haptic VirtaMed ArthroS simulators. Subsequently, each participant completed a validated simulator face validity questionnaire.ResultsThe ARTHRO Mentor active haptic system failed to achieve face validity with mean scores for external appearance (6.61), intra-articular appearance (4.78) and instrumentation (4.36) falling below the acceptable threshold (≥7.0). The ArthroS passive haptic simulator demonstrated satisfactory scores in all domains: external appearance (8.42), intra-articular appearance (7.65), instrumentation (7.21) and was significantly (p < 0.001) more realistic than ARTHRO Mentor for all metrics. 61% of participants gave scores ≥7.0 for questions pertaining to haptic feedback realism from intra-articular structures such as menisci and ACL/PCL for the ArthroS vs. 12% for ARTHRO Mentor. There was no difference in face-validity perception between intermediate and expert groups for either simulator (p > 0.05).ConclusionCurrent active haptic technology which employs motors to simulate tactile feedback fails to demonstrate sufficient face-validity or match the sophistication of passive haptic systems in high fidelity arthroscopy simulators. Textured rubber phantoms that mirror the anatomy and haptic properties of the knee joint provide a significantly more realistic training experience for both intermediate and expert arthroscopists.     

The effect of escalating feedback on the acquisition of psychomotor skills for laparoscopy

Background In the acquisition of new skills that are difficult to master, such as those required for laparoscopy, feedback is a crucial component of the learning experience. Optimally, feedback should accurately reflect the task performance to be improved and be proximal to the training experience. In surgery, however, feedback typically is in vivo. The development of virtual reality training systems currently offers new training options. This study investigated the effect of feedback type and quality on laparoscopic skills acquisition. Methods For this study, 32 laparoscopic novices were prospectively randomized into four training conditions, with 8 in each group. Group 1 (control) had no feedback. Group 2 (buzzer) had audio feedback when the edges were touched. Group 3 (voiced error) had an examiner voicing the word “error” each time the walls were touched. Group 4 (both) received both the audio buzzer and “error” voiced by the examiner All the subjects performed a maze-tracking task with a laparoscopic stylus inserted through a 5-mm port to simulate the fulcrum effect in minimally invasive surgery (MIS). A computer connected to the stylus scored an error each time the edge of the maze was touched, and the subjects were made aware of the error in the aforementioned manner. Ten 2-min trials were performed by the subjects while viewing a monitor. At the conclusion of training, all the subjects completed a 2-min trial of a simple laparoscopic cutting task, with the number of correct and incorrect incisions recorded. Results Group 4 (both) made significantly more correct incisions than the other three groups (F = 12.13; df = 3, 28; p < 0.001), and also made significantly fewer errors or incorrect incisions (F = 14.4; p < 0.0001). Group 4 also made three times more correct incisions and 7.4 times fewer incorrect incisions than group 1 (control). Conclusions The type and quality of feedback during psychomotor skill acquisition for MIS have a large effect on the strength of skills generalization to a simple MIS task and should be given serious consideration in curriculum design for surgical training using simulation tasks.     

Construct validity testing of a laparoscopic surgery simulator (Lap Mentor®)

BACKGROUND: Before surgical simulators can be implemented for assessment of surgical training, their construct validity should be assessed. METHODS: Nine novices (NOV), nine medical students (MS), and nine residents (RES) underwent a laparoscopic skills training on the virtual reality (VR) simulator Lap Mentor. Assessment of laparoscopic skill was based on parameters measured by the computer system before and after training. RESULTS: Significant difference existed between RES and NOV at seven of nine tasks before training on the VR simulator. After the training in some tasks significant differences were observed between the experienced group (RES) and the nonexperienced groups (MS and NOV) or between medical groups (RES and MS) and nonmedical group (NOV). CONCLUSIONS: Performance parameters of the Lap-Mentor can be used to distinguish between subjects with varying laparoscopic experience.     

Evaluation of a new virtual-reality training simulator for hysteroscopy

Background  To determine realism and training capacity of HystSim, a new virtual-reality simulator for the training of hysteroscopic interventions. Methods  Sixty-two gynaecological surgeons with various levels of expertise were interviewed at the 13^th Practical Course in Gynaecologic Endoscopy in Davos, Switzerland. All participants received a 20-min hands-on training on the simulator and filled out a four-page questionnaire. Twenty-three questions with respect to the realism of the simulation and the training capacity were answered on a seven-point Likert scale along with 11 agree–disagree statements concerning the HystSim training in general. Results  Twenty-six participants had performed more than 50 hysteroscopies (“experts”) and 36 equal to or fewer than 50 (“novices”). Four of 60 (6.6%) responding participants judged the overall impression as “7 – absolutely realistic”, 40 (66.6%) as “6 – realistic”, and 16 (26.6%) as “5 – somewhat realistic”. Novices (6.48; 95% confidence interval [CI] 6.28–6.7) rated the overall training capacity significantly higher than experts (6.08; 95% CI 5.85–6.3), however, high-grade acceptance was found in both groups. In response to the statements, 95.2% believe that HystSim allows procedural training of diagnostic and therapeutic hysteroscopy, and 85.5% suggest that HystSim training should be offered to all novices before performing surgery on real patients. Conclusion  Face validity has been established for a new hysteroscopic surgery simulator. Potential trainees and trainers assess it to be a realistic and useful tool for the training of hysteroscopy. Further systematic validation studies are needed to clarify how this system can be optimally integrated into the gynaecological curriculum.     

Proficiency-based virtual reality training significantly reduces the error rate for residents during their first 10 laparoscopic cholecystectomies

BACKGROUND: Virtual reality (VR) training has been shown previously to improve intraoperative performance during part of a laparoscopic cholecystectomy. The aim of this study was to assess the effect of proficiency-based VR training on the outcome of the first 10 entire cholecystectomies performed by novices. METHODS: Thirteen laparoscopically inexperienced residents were randomized to either (1) VR training until a predefined expert level of performance was reached, or (2) the control group. Videotapes of each resident's first 10 procedures were reviewed independently in a blinded fashion and scored for predefined errors. RESULTS: The VR-trained group consistently made significantly fewer errors (P = .0037). On the other hand, residents in the control group made, on average, 3 times as many errors and used 58% longer surgical time. CONCLUSIONS: The results of this study show that training on the VR simulator to a level of proficiency significantly improves intraoperative performance during a resident's first 10 laparoscopic cholecystectomies.     

Objective assessment of laparoscopic skills using a virtual reality stimulator

Background Virtual reality simulation has a great potential as a training and assessment tool of laparoscopic skills. The study was carried out to investigate whether the LapSim system (Surgical Science Ltd., Gothenburg, Sweden) was able to differentiate between subjects with different laparoscopic experience and thus to demonstrate its construct validity. Methods Subjects 24 were divided into two groups: experienced (performed > 100 laparoscopic procedures, n = 10) and beginners (performed <10 laparoscopic procedures, n = 14). Assessment of laparoscopic skills was based on parameters measured by the computer system. Results Experienced surgeons performed consistently better than the residents. Significant differences in the parameters time and economy of motion existed between the two groups in seven of seven tasks. Regarding error parameters, differences existed in most but not all tasks. Conclusion LapSim was able to differentiate between subjects with different laparoscopic experience. This indicates that the system measures skills relevant for laparoscopic surgery and can be used in training programs as a valid assessment tool.     

Construct validity of the LapSim: Can the LapSim virtual reality simulator distinguish between novices and experts?

Background Virtual reality simulators may be invaluable in training and assessing future endoscopic surgeons. The purpose of this study was to investigate if the results of a training session reflect the actual skill of the trainee who is being assessed and thereby establish construct validity for the LapSim virtual reality simulator (Surgical Science Ltd., Gothenburg, Sweden). Methods Forty-eight subjects were assigned to one of three groups: 16 novices (0 endoscopic procedures), 16 surgical residents in training (>10 but <100 endoscopic procedures), and 16 experienced endoscopic surgeons (>100 endoscopic procedures). Performance was measured by a relative scoring system that combines single parameters measured by the computer. Results The higher the level of endoscopic experience of a participant, the higher the score. Experienced surgeons and surgical residents in training showed statistically significant higher scores than novices for both overall score and efficiency, speed, and precision parameters. Conclusions Our results show that performance of the various tasks on the simulator corresponds to the respective level of endoscopic experience in our research population. This study demonstrates construct validity for the LapSim virtual reality simulator. It thus measures relevant skills and can be integrated in an endoscopic training and assessment program.     

Virtual Reality Simulation Training can Improve Inexperienced Surgeons'' Endovascular Skills

PURPOSE: The aim of this study was to evaluate virtual reality (VR) simulation for endovascular training of surgeons inexperienced in this technique. METHODS: Twenty consultant vascular surgeons were divided into those who had performed >50 endovascular procedures (e.g. aortic and carotid stent) as primary operator (n=8), and those having performed <10 procedures (n=12). To test for endovascular skill rather than procedural knowledge, all subjects performed a renal artery balloon angioplasty and stent procedure. The simulator uses real tools with active force feedback, and provides a realistic image of the virtual patient. Surgeons with endovascular skills performed two repetitions and those without completed six repetitions of the same task. The simulator recorded time taken for the procedure, the amount of contrast fluid used and total fluoroscopy time. RESULTS: Initially, surgeons with endovascular skills were significantly faster (median 571.5 vs. 900.0 s, p=0.039) and used less contrast fluid (19.1 vs. 42.9 ml, p=0.047) than inexperienced operators, though differences for fluoroscopy time were not significant (273 vs. 441 s, p=0.305). Over the six sessions, the inexperienced group made significant improvements in performance for time taken (p=0.007) and contrast fluid usage (p=0.021), achieving similar scores at the end of the training program to the experienced group. CONCLUSIONS: Surgeons with minimal endovascular experience can improve their time taken and contrast usage during short-phase training on a VR endovascular task. VR simulation may be useful for the early part of the learning curve for surgeons who wish to expand their endovascular interests.     

Surgical planning for microsurgical excision of cerebral arterio-venous malformations using virtual reality technology

Background  To evaluate the feasibility of surgical planning using a virtual reality platform workstation in the treatment of cerebral arterio-venous malformations (AVMs) Methods  Patient- specific data of multiple imaging modalities were co-registered, fused and displayed as a 3D stereoscopic object on the Dextroscope, a virtual reality surgical planning platform. This system allows for manipulation of 3D data and for the user to evaluate and appreciate the angio-architecture of the nidus with regards to position and spatial relationships of critical feeders and draining veins. We evaluated the ability of the Dextroscope to influence surgical planning by providing a better understanding of the angio-architecture as well as its impact on the surgeon’s pre- and intra-operative confidence and ability to tackle these lesions. Findings  Twenty four patients were studied. The mean age was 29.65 years. Following pre-surgical planning on the Dextroscope, 23 patients underwent microsurgical resection after pre-surgical virtual reality planning, during which all had documented complete resection of the AVM. Planning on the virtual reality platform allowed for identification of critical feeders and draining vessels in all patients. The appreciation of the complex patient specific angio-architecture to establish a surgical plan was found to be invaluable in the conduct of the procedure and was found to enhance the surgeon’s confidence significantly. Conclusion  Surgical planning of resection of an AVM with a virtual reality system allowed detailed and comprehensive analysis of 3D multi-modality imaging data and, in our experience, proved very helpful in establishing a good surgical strategy, enhancing intra-operative spatial orientation and increasing surgeon’s confidence.     

A framework for professionalism in surgery: what is important to medical students?

Background

The purposes of this study were to develop a comprehensive framework for professionalism in surgery and to determine which attributes are most valued by medical students.

Methods

A framework for professionalism in surgery, consisting of 11 attribute categories, was developed. All 3rd-year medical students (n = 168) participated in a focus group and completed a questionnaire regarding their perceptions about professionalism. Students' responses were transcribed verbatim, coded, and assigned attribute categories.

Results

Students rated respect as the most important attribute of professionalism (56%), followed by altruism (21%) and interpersonal skills (8%). Fifty-three percent of students witnessed unprofessional behavior among faculty members while on the surgical clerkship. Of these incidents, 74% were related to respect, 28% to practice improvement, and 1% to altruism.

Conclusions

Respect was rated as the single most important characteristic of professionalism and was the attribute with the most witnessed violations.     

Endoscopic Sinus Surgery Simulator as a teaching tool for anatomy education

BACKGROUND: Virtual reality simulators provide an effective learning environment and are widely used. This study evaluated the Endoscopic Sinus Surgery Simulator (ES3; Lockheed Martin) as a tool for anatomic education. METHODS: Two medical student groups (experimental, n = 8; control, n = 7) studied paranasal sinus anatomy using either the simulator or textbooks. Their knowledge was then tested on the identification of anatomic structures on a view of the nasal cavities. RESULTS: The mean scores were 9.4 +/- 0.5 and 5.1 +/- 3.0 out of 10 for the simulator and textbook groups, respectively (P = .009). Moreover, the simulator group completed the test in a significantly shorter time, 5.9 +/- 1.1 versus 8.3 +/- 2.0 minutes (P = .021). A survey asking the students to rate their respective study modality did not materialize significant differences. CONCLUSION: The ES3 can be an effective tool in teaching sinonasal anatomy. This study may help shape the future of anatomic education and the development of modern educational tools.     

The importance of haptic feedback in laparoscopic suturing training and the additive value of virtual reality simulation

Introduction Previous studies on the difference between physical, augmented and virtual reality (VR) simulation state that haptic feedback is an important feature in laparoscopic suturing simulation. Objective assessment is important to improve skills during training. This study focuses on the additive value of VR simulation for laparoscopic suturing training. Methods All participants of several European Association for Endoscopic Surgery (EAES)-approved laparoscopic skills courses (N = 45) filled out a questionnaire on their opinion on laparoscopic suturing training. Additionally, participants with little or no laparoscopic suturing experience were allotted to two groups: group A (N = 10), who started training on the box trainer and subsequently the VR simulator (SimSurgery), and group B (N = 10), who began on the VR simulator followed by the box. Finally, suturing and knot-tying skills were assessed by an expert observer, using a standard evaluation form (eight items on five-point-Likert scale). The same was done after the initial training on the box in group A, as a control. Significant differences were calculated with the independent-sample t-test and the paired t-test. Results The total score of group A was higher than both group B and control (means of 30.80, 27.60, 28.20, respectively), but not significantly. The only tendency to a significant difference between group A and B was found in ‘taking proper bites’ (mean 4.10 versus 3.60, p = 0.054). All the participants scored the features of the box trainer significantly higher than those of the VR simulator (p < 0.001), 46.7% was of the opinion that the box alone would be sufficient for laparoscopic suturing training. Conclusion From this study we can conclude that VR simulation does not have a significant additional value in laparoscopic suturing training, over traditional box trainers. One should consider that the future development in VR simulation should focus on basic skills and component tasks of procedural training in laparoscopic surgery, rather than laparoscopic suturing.