Extended,virtual and augmented reality in thoracic surgery: a systematic review

 Open in a separate windowOBJECTIVESExtended reality (XR), encompassing both virtual reality (VR) and augmented reality, allows the user to interact with a computer-generated environment based on reality. In essence, the immersive nature of VR and augmented reality technology has been warmly welcomed in all aspects of medicine, gradually becoming increasingly feasible to incorporate into everyday practice. In recent years, XR has become increasingly adopted in thoracic surgery, although the extent of its applications is unclear. Here, we aim to review the current applications of XR in thoracic surgery.METHODSA systematic database search was conducted of original articles that explored the use of VR and/or augmented reality in thoracic surgery in EMBASE, MEDLINE, Cochrane database and Google Scholar, from inception to December 2020.RESULTSOur search yielded 1494 citations, of which 21 studies published from 2007 to 2019 were included in this review. Three main areas were identified: (i) the application of XR in thoracic surgery training; (ii) preoperative planning of thoracic procedures; and (iii) intraoperative assistance. Overall, XR could produce progression along the learning curve, enabling trainees to reach acceptable standards before performing in the operating theatre. Preoperatively, through the generation of 3D-renderings of the thoracic cavity and lung anatomy, VR increases procedural accuracy and surgical confidence through familiarization of the patient’s anatomy. XR-assisted surgery may have therapeutic use particularly for complex cases, where conventional methods would yield inadequate outcomes due to inferior accuracy.CONCLUSIONXR represents a salient step towards improving thoracic surgical training, as well as enhancing preoperative planning and intraoperative guidance.     

Early exposure to haptic feedback enhances performance in surgical simulator training: a prospective randomized crossover study in surgical residents

Background In the literature of skill acquisition and transfer of skills, it often is assumed that the rate of skill acquisition depends on what has been learned in a similar context (i.e., surgical simulators providing haptic feedback). This study aimed to analyze whether the addition of haptic feedback early in the training phase for image-guided surgical simulation improves performance. Methods A randomized crossover study design was used, in which 38 surgical residents were randomized to begin a 2-h simulator training session with either haptic or nonhaptic training followed by crossover after 1 h. The graphic context was a virtual upper abdomen. The residents performed two diathermy tasks. Two validated tests were used to control for differences in visual–spatial ability: the BasIQ general cognitive ability test and Mental Rotation Test A (MRT-A). Results After 2 h of training, the group that had started with haptic feedback performed the two diathermy tasks significantly better (p < 0.05, unpaired t-test). Only the group that had started with haptic training significantly improved during the last 1-h session (p < 0.01, paired t-test). Conclusion The findings indicate that haptic feedback could be important in the early training phase of skill acquisition in image-guided surgical simulator training.     

Virtual reality simulator training equals mechanical robotic training in improving robot-assisted basic suturing skills

Background This study aimed to investigate the effect of a virtual reality simulator on the learning of basic robotic suturing skills. Methods Two randomized groups of students underwent a controlled training program. Both groups completed an identical test before and after training. The increase in the number of stitches placed during the pretest and posttest was used as an objective measure of the training effect. To evaluate the subjective feeling of understanding and mastering, the students indicated this on a visual analog scale. Results Both groups showed a significant increase in the number of stitches placed during the posttest, and an increase in subjective feeling of understanding and mastering. The increase did not differ between the groups, indicating that the virtual reality simulator equaled the mechanical trainer in training of robotic suturing technique. Conclusions Training in basic robot-assisted suturing skills using a virtual reality simulator without additional training equaled training using a mechanical simulator.     

Usefulness of a virtual reality simulator or training box for endoscopic surgery training

This study investigated whether the use of a simulator for endoscopic surgery training improves the performance of actual operations. For the study, 16 medical students were divided into three groups: a virtual reality (VR) simulator group (n = 6), a training box (TB) group (n = 6), and a control group (n = 4). The VR and TB groups received 2 h of training per day for 5 days, after which they were requested to perform intestinal dissection, to close a gastric perforation, and to perform cholecystectomy in pigs. Performance was assessed on the basis of the operating time and the error score. Although there were no differences between the three groups in terms of the total operating time or error score, the VR and TB groups required less time for closure of the gastric perforation than the control group. In addition, the operating time decreased as actual operating experience increased in the VR group. In the TB group, the time for closure of a gastric perforation was shorter when the supervisor had seen the operation before training. These findings demonstrated that a simulator is useful for acquiring psychomotor skills, but does not immediately enable clinical performance of an operation. More actual experience and good supervision are essential for increasing the effectiveness of training with the VR and TB simulators, respectively.     

虚拟技术对21世纪微创外科发展的影响

20世纪后期，建立在高新技术基础上的虚拟技术发展迅速，为微创外科的发展提供了强有力的手段，在微创外科领域的应用日益广泛，并对微创外科的发展产生了深远的影响。虚拟技术充实和更新了微创外科的诊疗理念，拓展了微创外科的诊疗范围，提高了微创外科的诊疗效果，并且促进了微创诊疗器械的不断发展和更新。但由于虚拟技术目前尚处于起步阶段，虚拟技术的开发不仅需要高层次复合型人才，还需要借助昂贵的设备和特殊的器械，因此将虚拟技术应用于微创外科领域时，应选择合适的手术适应证，有选择有重点的逐步开展，同时应不断加强虚拟技术的基础和应用研究，努力促使其真正成为微创或无创治疗的有效手段。     

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.     

Perception and use of minimal access surgery simulators in pediatric surgery training programs

Background/Purpose

In the current time-restricted training environment, simulator use in surgical teaching is receiving increasing attention. A large body of literature addresses simulators' effectiveness in surgical education. No prior studies assess how widely simulators are actually being used or attitudes about their effectiveness of those involved in training.

Methods

Surveys were e-mailed to all current pediatric surgery trainees and training directors. Queries examined respondents' perceptions about surgical simulators' usefulness and to what extent they are used in their programs. Other questions assessed obstacles to simulator use.

Results

Response rates were high (47% of program directors and 67% of current fellows). Nearly all respondents felt laparoscopic simulators improve training efficiency (88%). About half (55%) report regular simulator availability to trainees. Only 21% of programs have current or planned simulation curricula. Less than half of the training directors (32%) and about half of the fellows (55%) felt they have actually significantly improved trainees' skills.

Conclusions

Trainees and training directors placed significant importance on simulator use in pediatric surgery training. However, most did not feel that simulators had actually improved the trainees' laparoscopic skills. Wider availability of simulation laboratories and protected time for using them would enhance the impact of simulators on pediatric surgery training.     

Visual clues act as a substitute for haptic feedback in robotic surgery

OBJECTIVE: The lack of haptic feedback (HF) in robotic surgery is one of the major concerns of novice surgeons to that field. The superior visual appearances acquired during robotic surgery may give clues that make HF less important. METHODS: We surveyed 52 individuals on their perception of HF during robotic surgery. The first group of 34 surgically inexperienced people used the da Vinci robot for their first time (drylab). The second group included 8 laparoscopic surgeons with experience up to a fifth robotic operation. The third group included 10 surgical experts with substantial experience (150-650 robotic cases). Visual analog assessment was made of perception of HF, how much HF was missed, how much the absence of HF impaired the operators' level of comfort. Robotic experts were asked if complications have occurred as a result of a lack of HF. RESULTS: Of the first group, 50% reported the perception of HF, as did 55% of the second group and 100% of the third group (difference between group 1 and group 3: p < 0.05). The first group missed HF for 6.5; the second group for 4.3, and the third group for 4 (difference between groups 1 and 3: p < 0.05). The surgical experts claimed to have missed HF for 7.2 s when they first started robotic surgery (Difference to now: p < 0.05). The lack of HF caused discomfort for the first group of 4; for the second group of 4,4, and for the third group of 2,6. One complication was reported by the robotic experts as resulting from the lack of HF. CONCLUSIONS: The data support the conclusion that even beginners quickly experience the perception of HF when performing robotic surgery. With more experience, perception of HF and the level of comfort with robotic surgery increases significantly. This perception of HF makes "real" HF less important and demonstrates that its importance is overestimated by novices in robotic surgery.     

Impact of hand dominance,gender, and experience with computer games on performance in virtual reality laparoscopy

Background: The impact of gender and hand dominance on operative performance may be a subject of prejudice among surgeons, reportedly leading to discrimination and lack of professional promotion. However, very little objective evidence is available yet on the matter. This study was conducted to identify factors that influence surgeons performance, as measured by a virtual reality computer simulator for laparoscopic surgery. Methods: This study included 25 surgical residents who had limited experience with laparoscopic surgery, having performed fewer than 10 laparoscopic cholecystectomies. The participants were registered according to their gender, hand dominance, and experience with computer games. All of the participants performed 10 repetitions of the six tasks on the Minimally Invasive Surgical Trainer—Virtual Reality (MIST-VR) within 1 month. Assessment of laparoscopic skills was based on three parameters measured by the simulator: time, errors, and economy of hand movement. Results: Differences in performance existed between the compared groups. Men completed the tasks in less time than women (p = 0.01, Mann–Whitney test), but there was no statistical difference between the genders in the number of errors and unnecessary movements. Individuals with right hand dominance performed fewer unnecessary movements (p = 0.045, Mann–Whitney test), and there was a trend toward better results in terms of time and errors among the residence with right hand dominance than among those with left dominance. Users of computer games made fewer errors than nonusers (p = 0.035, Mann–Whitney test). Conclusions: The study provides objective evidence of a difference in laparoscopic skills between surgeons differing gender, hand dominance, and computer experience. These results may influence the future development of training program for laparoscopic surgery. They also pose a challenge to individuals responsible for the selection and training of the residents.     

Perceptions of surgical specialists in general surgery, orthopaedic surgery, urology and gynaecology on teaching endoscopic surgery in The Netherlands

Background Specific training in endoscopic skills and procedures has become a necessity for profession with embedded endoscopic techniques in their surgical palette. Previous research indicates endoscopic skills training to be inadequate, both from subjective (resident interviews) and objective (skills measurement) viewpoint. Surprisingly, possible shortcomings in endoscopic resident education have never been measured from the perspective of those individuals responsible for resident training, e.g. the program directors. Therefore, a nation-wide survey was conducted to inventory current endoscopic training initiatives and its possible shortcomings among all program directors of the surgical specialties in the Netherlands. Methods Program directors for general surgery, orthopaedic surgery, gynaecology and urology were surveyed using a validated 25–item questionnaire. Results A total of 113 program directors responded (79%). The respective response percentages were 73.6% for general surgeons, 75% for orthopaedic surgeon, 90.9% for urologists and 68.2% for gynaecologists. According to the findings, 35% of general surgeons were concerned about whether residents are properly skilled endoscopically upon completion of training. Among the respondents, 34.6% were unaware of endoscopic training initiatives. The general and orthopaedic surgeons who were aware of these initiatives estimated the number of training hours to be satisfactory, whereas the urologists and gynaecologists estimated training time to be unsatisfactory. Type and duration of endoscopic skill training appears to be heterogeneous, both within and between the specialties. Program directors all perceive virtual reality simulation to be a highly effective training method, and a multimodality training approach to be key. Respondents agree that endoscopic skills education should ideally be coordinated according to national consensus and guidelines. Conclusions A delicate balance exists between training hours and clinical working hours during residency. Primarily, a re-allocation of available training hours, aimed at core-endoscopic basic and advanced procedures, tailored to the needs of the resident and his or her phase of training is in place. The professions need to define which basic and advanced endoscopic procedures are to be trained, by whom, and by what outcome standards. According to the majority of program directors, virtual reality (VR) training needs to be integrated in procedural endoscopic training courses.     

以磁吻合技术:迎接微创外科新未来

磁性压迫吻合技术(magnetic compression anastomosis,MCA)是利用永磁材料制成的吻合装置间的引力压迫脏器壁层造成局部缺血坏死而使管腔再通的非手术治疗方法.在血管介入技术的基础上利用磁性吻合技术可以实现腔内动、静脉吻合,显著缩短吻合时间,减少组织器官缺血损伤.MCA在临床上还可用于实现空腔...     

Methods and mechanisms for contact feedback in a robot-assisted minimally invasive environment

Providing a surgeon with information regarding contacts made between instruments and tissue during robot-assisted interventions can improve task efficiency and reliability. In this report, different methods for feedback of such information to the surgeon are discussed. It is hypothesized that various methods of contact feedback have the potential to enhance performance in a robot-assisted minimally invasive environment. To verify the hypothesis, novel mechanisms needed for incorporating contact feedback were designed, including a surgeon-robot interface with full force feedback capabilities and a surgical end-effector with full force sensing capabilities, that are suitable for minimally invasive applications. These two mechanisms were used to form a robotic "master-slave" test bed for studying the effect of contact feedback on the system and user performance. Using the master-slave system, experiments for surgical tasks involving soft tissue palpation were conducted. The performance of the master-slave system was validated in terms of criteria that assess the accurate transmission of task-related information to the surgeon, which is critical in the context of soft tissue surgical applications. Moreover, using a set of experiments involving human subjects, the performance of several users in carrying out the task was compared among different methods of contact feedback.     

Ergonomic testing of two different types of handles via virtual reality simulation

Background Ergonomics in laparoscopic surgery is an unsolved problem. Deficiencies of the instrument handles are well-known and described in several reports and studies. Today, virtual training modules for laparoscopic surgery are available. The aim of this study was to evaluate the ability of a virtual reality (VR) simulator to determine the ergonomic properties of two different laparoscopic instrument handles. Methods Two different types of handles, a ring and an axial handle from Richard Wolf, were used to perform the short clip and cut task of the Xitact 500 LS simulator. The task was repeated every 2 days for a period of 5 weeks. After every trial the volunteers were asked structured questions about their preferences while using the two handles. Results The axial handle was superior or equal to the ring handle in all criteria. Learning curves over the entire time and day by day were similar. No differences were found for travel distances and error rates, but task times were different for both handles. The subjects preferred the axial handle at the end of the study. Conclusion It is possible to determine differences in ergonomics of handle design with a VR trainer. In this study, the Richard Wolf axial handle was superior to the ring handle.     

Assessing the learning curve for the acquisition of laparoscopic skills on a virtual reality simulator

Background The aim of this study was to develop summary metrics and assess the construct validity for a virtual reality laparoscopic simulator (LapSim) by comparing the learning curves of three groups with different levels of laparoscopic expertise.Methods Three groups of subjects (‘expert’, ‘junior’, and ‘naïve’) underwent repeated trials on three LapSim tasks. Formulas were developed to calculate scores for efficiency (‘time-error’) and economy of ‘motion’ (‘motion’) using metrics generated by the software after each drill. Data (mean ± SD) were evaluated by analysis of variance (ANOVA). Significance was set at p < 0.05.Results All three groups improved significantly from baseline to final for both ‘time-error’ and ‘motion’ scores. There were significant differences between groups in time error performances at baseline and final, due to higher scores in the ‘expert’ group. A significant difference in ‘motion’ scores was seen only at baseline.Conclusion We have developed summary metrics for the LapSim that differentiate among levels of laparoscopic experience. This study also provides evidence of construct validity for the LapSim.Presented in part at the annual meeting of The Society of American Gastrointestinal and Endoscopic Surgeons (SAGES), Denver, CO, USA April 2004     

Technical skills assessment as part of the selection process for a fellowship in minimally invasive surgery

Introduction

Selection of candidates for surgical fellowships has traditionally been based on subjective evaluations by the program directors and references from previous positions. The introduction of well-validated objective methods of assessment has allowed us to evaluate candidates’ technical skills and base the selection process on objective, reliable, and transparent criteria. The aim of the study was to assess the applicability of such methods in current practice.

Materials and methods

Prospective study. Eight surgeons, applying for a fellowship position in minimally invasive surgery (MIS), performed a previously validated assessment curriculum using a Virtual-Reality Laparoscopic Trainer (LapSim^® 3.0, Surgical Science, Gothenburgh, Sweden). Technical performance was evaluated using criteria registered by the simulator, i.e., time, error score, and efficiency of movements score. Candidates performed all the tasks in easy end medium level until reaching predefined criteria. If proficiency criteria were not achieved on easy or medium level after nine repetitions the test was considered as failed. Additionally, all applicants underwent an interview by two independent attending surgeons. Each applicant received a grade on a ten-point scale.

Results

Five out of the eight candidates failed the technical skills assessment test. One candidate failed to achieve proficiency criteria on easy level, one on medium, and three on difficult level. Evaluation scores, based on the interview of the candidates showed a good interrater reliability (Cronbach’s α = 0.8). There was no significant correlation between the interviewers rating, and the applicants technical skills demonstrated during the test on the VR trainer (Spearman’s ρ = 0.182, p = 0.696).

Conclusions

Evaluations by senior surgeons are reproducible and reliable. The introduction of technical skills assessment has the potential to improve the current method of candidate selection, making it more valid, objective, and transparent.     

Training in tasks with different visual-spatial components does not improve virtual arthroscopy performance

Background: We earlier showed that training in the Procedicus KSA Simulator improves the performance of tasks done later in the same simulator. However, it is still unclear how performance in a specific visual-spatial simulator context may change after training in other simulators with different visual-spatial components. In particular, the aim of this study was to test whether performance in the Procedicus Virtual Arthroscopy (VA) Knee Simulator would remain unchanged after a training session in three other simulators with different visual-spatial components. Methods: Twenty-eight medical students participated in a quasi-transfer study. They were randomly allocated to an experimental group (n = 14) and a control group (n = 14). Results: Performance in the Procedicus VA Knee Simulator did not improve after training in other simulators with different visual-spatial components (t-test p = NS). No significant correlation was found between the Procedicus VA Knee and the Minimally Invasive Surgical Trainer (MIST) simulators. Conclusion: One hour of training in different visual-spatial contexts was not enough to improve the performance in virtual arthroscopy tasks. It cannot be excluded, however, that experienced trainees could improve their performance, because perceived similarity between different situations is influenced by many psychological factors, such as the knowledge or expertise of the person performing the transfer task.