What is going on in augmented reality simulation in laparoscopic surgery?

Background  To prevent unnecessary errors and adverse results of laparoscopic surgery, proper training is of paramount importance. A safe way to train surgeons for laparoscopic skills is simulation. For this purpose traditional box trainers are often used, however they lack objective assessment of performance. Virtual reality laparoscopic simulators assess performance, but lack realistic haptic feedback. Augmented reality (AR) combines a virtual reality (VR) setting with real physical materials, instruments, and feedback. This article presents the current developments in augmented reality laparoscopic simulation. Methods  Pubmed searches were performed to identify articles regarding surgical simulation and augmented reality. Identified companies manufacturing an AR laparoscopic simulator received the same questionnaire referring to the features of the simulator. Results  Seven simulators that fitted the definition of augmented reality were identified during the literature search. Five of the approached manufacturers returned a completed questionnaire, of which one simulator appeared to be VR and was therefore not applicable for this review. Conclusion  Several augmented reality simulators have been developed over the past few years and they are improving rapidly. We recommend the development of AR laparoscopic simulators for component tasks of procedural training. AR simulators should be implemented in current laparoscopic training curricula, in particular for laparoscopic suturing training.     

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.     

Minimally invasive vs open distal metatarsal osteotomy for hallux valgus - A systematic review and meta-analysis

BackgroundNumerous publications of the late 20th century have presented the radiological outcome of open technique for distal metatarsal osteotomy for mild to moderate hallux valgus and the clinical outcomes by means of well-established scoring systems which have been published and make these open techniques today’s benchmark and gold standard. Minimally invasive procedures reduce surgical trauma because they are performed without large incisions, and injury to the soft tissues is limited. This has the theoretical advantages of improved recovery and decreased rehabilitation times. There is however limited literature to prove the same for minimally invasive surgery for hallux valgus.Our aim was thus to pool all available comparative literature on minimally invasive hallux valgus surgery done for mild to moderate hallux valgus versus open surgical approaches.MethodsA PubMed, Embase and Scopus search was performed using the keywords (‘hallux valgus’ OR bunion) AND (‘minimally invasive’ OR percutaneous) AND osteotomy. A total of 473 records were identified and out of which nine studies were included in the final review.ResultsMost available studies are either randomized control trials, or prospective cohort studies providing good level of evidence. Radiological analysis showed similar correction with both MIS and open osteotomies. In functional analysis results were different with open techniques providing better results in terms of AOFAS score. (p < 0.0001). VAS score and complication rate were similar in both groups.Discussion/conclusionWe conclude that based on available literature MIS provides equivalent radiological outcomes with respect to open surgery but functionally despite the promising results (good to excellent in most series), the outcomes in terms of function are not as good as open surgery. MIS techniques provide satisfactory outcomes for mild-to-moderate severity of hallux valgus though not as good as open surgery. There is evolving literature for this relatively new procedure. Longer duration of follow up and bigger numbers would allow for more meaningful data analysis and conclusions to be drawn as more studies come forward.     

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.     

Learning curve could affect oncologic outcome of minimally invasive radical hysterectomy for cervical cancer

Background/ObjectiveRecent prospective studies have shown poorer oncologic outcomes following minimally invasive surgery, which has led many surgeons to deeply inspect their practices. We reviewed our experience and evaluated the results of radical hysterectomy in patients with early stage cervical cancer.MethodsThis retrospective study included patients with early stage cervical cancer (Ia1 - IIa1) who were treated with radical hysterectomy from May 2006 to Dec 2016. Patients were divided into three groups according to the surgical approach: radical abdominal hysterectomy (RAH), laparoscopic radical hysterectomy (LRH), and robot-assisted radical hysterectomy (RRH).ResultsLearning curves of each type of surgery were obtained using the cumulative sum method. Survival rates were compared using Kaplan–Meier curves. To analyze the learning curve of a single surgeon, 89 patients were selected from the whole population. Learning curves of each group showed two distinct phases. The minimum number of cases required to achieve surgical improvement were 16 in RAH, 13 in LRH, and 21 in RRH. Progression-free survival (PFS) and overall survival did not vary between RAH and minimally invasive surgery (MIS) (p = .828 and p = .757, respectively). However, when stratified by the phases of the learning curves, patients included in the early phase of MIS showed a poorer PFS (p = .014).ConclusionsSurgical proficiency could significantly affect the oncologic outcome in MIS. A prospective study regarding sufficient surgical competence is necessary for elaborate analysis of the feasibility of minimally invasive radical hysterectomy.     

Effects of Virtual Reality Simulator Training Method and Observational Learning on Surgical Performance

Background  

Virtual reality (VR) simulators and Web-based instructional videos are valuable supplemental training resources in surgical programs, but it is unclear how to optimally integrate them into minimally invasive surgical training.     

力触觉反馈系统在现代数字化外科的应用及研究进展

通过将力触觉反馈系统应用到现代数字化外科,为医用外科机器人、虚拟现实手术模拟系统及远程外科提供力触觉信息,可有效提高外科手术精确性和灵活性、增加手术安全性并缩短手术时间。本文对力触觉反馈系统在现代数字化外科的应用及研究进展进行综述。     

Ergonomics, user comfort, and performance in standard and robot-assisted laparoscopic surgery

Background  Robot-assisted surgical systems have been introduced to improve the outcome of minimally invasive surgery. These systems also have the potential to improve ergonomics for the surgeon during endoscopic surgery. This study aimed to compare the user’s mental and physical comfort in performing standard laparoscopic and robot-assisted techniques. Surgical performance also was analyzed. Methods  In this study, 16 surgically inexperienced participants performed three tasks using both a robotic system and standard laparoscopic instrumentation. Distress was measured using questionnaires and an ambulatory monitoring system. Surgical performance was analyzed with time-action analysis. Results  The physiologic parameters (p = 0.000), the questionnaires (p = 0.000), and the time-action analysis (p = 0.001) favored the robot-assisted group in terms of lower stress load and an increase in work efficiency. Conclusion  In this experimental setup, the use of a robot-assisted surgical system was of value in both cognitive and physical stress reduction. Robotic assistance also demonstrated improvement in performance.     

Ongoing deficits in resident training for minimally invasive surgery

Patient preference has driven the adoption of minimally invasive surgery (MIS) techniques and altered surgical practice. MIS training in surgical residency programs must teach new skill sets with steep learning curves to enable residents to master key procedures. Because no nationally recognized MIS curriculum exists, this study asked experts in MIS which laparoscopic procedures should be taught and how many cases are required for competency. Expert recommendations were compared to the number of cases actually performed by residents (Residency Review Committee [RRC] data). A detailed survey was sent nationwide to all surgical residency programs (academic and private) known to offer training in MIS and/or have a leader in the field. The response rate was approximately 52%. RRC data were obtained from the resident statistics summary report for 1998–1999. Experts identified core procedures for MIS training and consistently voiced the opinion that to become competent, residents need to perform these procedures many more times than the RRC data indicate they currently do. At present, American surgical residency programs do not meet the suggested MIS case range or volume required for competency. Residency programs need to be restructured to incorporate sufficient exposure to core MIS procedures. More expert faculty must be recruited to train residents to meet the increasing demand for laparoscopy. Presented at the Forty-Second Annual Meeting of The Society for Surgery of the Alimentary Tract, Atlanta, Georgia, May 20–23, 2001 (oral presentation). Supported in part by an educational grant from Tyco/U.S. Surgical Corporation.     

Haptic interaction in robot-assisted endoscopic surgery: a sensorized end-effector

Conventional endoscopic surgery has some drawbacks that can be addressed by using robots. The robotic systems used for surgery are still in their infancy. A major deficiency is the lack of haptic feedback to the surgeon. In this paper, the benefits of haptic feedback in robot-assisted surgery are discussed. A novel robotic end-effector is then described that meets the requirements of endoscopic surgery and is sensorized for force/ torque feedback. The endoscopic end-effector is capable of non-invasively measuring its interaction with tissue in all the degrees of freedom available during endoscopic manipulation. It is also capable of remotely actuating a tip and measuring its interaction with the environment without using any sensors on the jaws. The sensorized end-effector can be used as the last arm of a surgical robot to incorporate haptic feedback and/or to evaluate skills and learning curves of residents and surgeons in endoscopic surgery.     

Reviewing the technological challenges associated with the development of a laparoscopic palpation device

Minimally invasive surgery (MIS) has heralded a revolution in surgical practice, with numerous advantages over open surgery. Nevertheless, it prevents the surgeon from directly touching and manipulating tissue and therefore severely restricts the use of valuable techniques such as palpation. Accordingly a key challenge in MIS is to restore haptic feedback to the surgeon. This paper reviews the state‐of‐the‐art in laparoscopic palpation devices (LPDs) with particular focus on device mechanisms, sensors and data analysis. It concludes by examining the challenges that must be overcome to create effective LPD systems that measure and display haptic information to the surgeon for improved intraoperative assessment. Copyright © 2012 John Wiley & Sons, Ltd.     

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.     

Ergonomic assessment of neck posture in the minimally invasive surgery suite during laparoscopic cholecystectomy

Background  With the expanding implementation of minimally invasive surgery, the operating team is confronted with challenges in the field of ergonomics. Visual feedback is derived from a monitor placed outside the operating field. This crossover trial was conducted to evaluate and compare neck posture in relation to monitor position in a dedicated minimally invasive surgery (MIS) suite and a conventional operating room. Methods  Assessment of the neck was conducted for 16 surgeons, assisting surgeons, and scrub nurses performing a laparoscopic cholecystectomy in both types of operating room. Flexion and rotation of the cervical spine were measured intraoperatively using a video analysis system. A two-question visual analog scale (VAS) questionnaire was used to evaluate posture in relation to the monitor position. Results  Neck rotation was significantly reduced in the MIS suite for the surgeon (p = 0.018) and the assisting surgeon (p < 0.001). Neck flexion was significantly improved in the MIS suite for the surgeon (p < 0.001) and the scrub nurse (p = 0.018). On the questionnaire, the operating room team scored their posture significantly higher in the MIS suite and also indicated fewer musculoskeletal complaints. Conclusions  The ergonomic quality of the neck posture is significantly improved in the MIS suite for the entire operating room team.     

Application of haptic feedback to robotic surgery

Robotic surgical systems have greatly contributed to the advancement of minimally invasive endoscopic surgery. However, current robotic systems do not provide tactile or haptic feedback to the operating surgeon. Under certain circumstances, particularly with the manipulation of delicate tissues and suture materials, this may prove to be a significant irritation. We hypothesize that haptic feedback, in the form of sensory substitution, facilitates the performance of surgical knot tying. This preliminary study describes evidence that visual sensory substitution permits the surgeon to apply more consistent, precise, and greater tensions to fine suture materials without breakage during robot-assisted knot tying.     

Validated robotic laparoscopic surgical training in a virtual-reality environment

Background  A robotic virtual-reality (VR) simulator has been developed to improve robot-assisted training for laparoscopic surgery and to enhance surgical performance in laparoscopic skills. The simulated VR training environment provides an effective approach to evaluate and improve surgical performance. This study presents our findings of the VR training environment for robotic laparoscopy. Methods  Eight volunteers performed two inanimate tasks in both the VR and the actual training environment. The tasks were bimanual carrying (BC) and needle passing (NP). For the BC task, the volunteers simultaneously transferred two plastic pieces in opposite directions five times consecutively. The same volunteers passed a surgical needle through six pairs of holes in the NP task. Both tasks require significant bimanual coordination that mimics actual laparoscopic skills. Data analysis included time to task completion, speed and distance traveled of the instrument tip, as well as range of motion of the subject’s wrist and elbow of the right arm. Electromyography of the right wrist flexor and extensor were also analyzed. Paired t-tests and Pearson’s r were used to explore the differences and correlations between the two environments. Results  There were no significant differences between the actual and the simulated VR environment with respect to the BC task, while there were significant differences in almost all dependent parameters for the NP task. Moderate to high correlations for most dependent parameters were revealed for both tasks. Conclusions  Our data shows that the VR environment adequately simulated the BC task. The significant differences found for the NP task may be attributed to an oversimplification in the VR environment. However, they do point to the need for improvements in the complexity of our VR simulation. Further research work is needed to develop effective and reliable VR environments for robotic laparoscopic training.     

Survey of resident training in robotic surgery

Robotics has been recognized as a major driving force in the advancement of minimally invasive surgery. However, the extent to which General Surgery residents are being trained to use robotic technology has never been assessed. A survey was sent to program directors of accredited General Surgery training programs to determine the prevalence and application of robotics in surgical training programs. Responses were tabulated and analyzed. Thirty-three per cent indicated interest in minimally invasive surgery. Twelve per cent of responders have used robotics in their practice, and 65 per cent felt robotics will play an important role in the future of General Surgery. Currently residents from 14 per cent of the responding training programs have exposure to robotic technology, and residents from an additional 4 per cent of these programs have limited didactic exposure. Program directors from 23 per cent of responding programs identified plans to incorporate robotics into their program. Robotics have been shown to make standard endoscopic surgical procedures more efficient and cost-effective as well as allowing a variety of procedures that were only possible with conventional methods to be completed with minimally invasive techniques. This new technology promises to be a large part of the future of surgery and as such deserves more attention in the training of General Surgery residents.     

Augmented versus Virtual Reality Laparoscopic Simulation: What Is the Difference?

BACKGROUND: Virtual reality (VR) is an emerging new modality for laparoscopic skills training; however, most simulators lack realistic haptic feedback. Augmented reality (AR) is a new laparoscopic simulation system offering a combination of physical objects and VR simulation. Laparoscopic instruments are used within an hybrid mannequin on tissue or objects while using video tracking. This study was designed to assess the difference in realism, haptic feedback, and didactic value between AR and VR laparoscopic simulation. METHODS: The ProMIS AR and LapSim VR simulators were used in this study. The participants performed a basic skills task and a suturing task on both simulators, after which they filled out a questionnaire about their demographics and their opinion of both simulators scored on a 5-point Likert scale. The participants were allotted to 3 groups depending on their experience: experts, intermediates and novices. Significant differences were calculated with the paired t-test. RESULTS: There was general consensus in all groups that the ProMIS AR laparoscopic simulator is more realistic than the LapSim VR laparoscopic simulator in both the basic skills task (mean 4.22 resp. 2.18, P < 0.000) as well as the suturing task (mean 4.15 resp. 1.85, P < 0.000). The ProMIS is regarded as having better haptic feedback (mean 3.92 resp. 1.92, P < 0.000) and as being more useful for training surgical residents (mean 4.51 resp. 2.94, P < 0.000). CONCLUSIONS: In comparison with the VR simulator, the AR laparoscopic simulator was regarded by all participants as a better simulator for laparoscopic skills training on all tested features.     

Objective Psychomotor Skills Assessment of Experienced, Junior, and Novice Laparoscopists with Virtual Reality

Objective assessment of psychomotor skills in surgery is now a priority; however, this assessment is difficult to achieve because of measurement difficulties associated with the reliability and validity of assessing surgical skills in vivo and in the laboratory. In this study virtual reality (VR) was used to overcome these problems in the objective psychomotor assessment of senior, junior, and novice laparoscopists. Twelve experienced laparoscopic surgeons (performed >50 Minimal Access Surgery (MAS) procedures), 12 inexperienced laparoscopic surgeons (<10 MAS procedures), and 12 laparoscopic novices (no MAS procedures) participated in the study. Each subject completed all six tasks of the Minimally Invasive Surgical Trainer; Virtual Reality (MIST VR). In comparison to the other groups, experienced laparoscopic surgeons performed the tasks significantly (p < 0.01) faster, had a lower error rate, were more economic in their movement of surgical instruments and in the use of diathermy. As a group they also showed greater consistency in their performance. MIST VR distinguished between the three groups of laparoscopists. VR provides a useful objective assessment tool for evaluating psychomotor skills for laparoscopic surgery.     

Effects of experience on force perception threshold in minimally invasive surgery

Background

Distorted haptic feedback by the surgical instrumentation is a major problem in minimally invasive surgery (MIS). Friction force generated by the rubber seal in the trocars masks the haptic information needed to perceive the properties and structure of the target tissue, resulting in an increased haptic perception threshold in naïve subjects. This can lead to over application of forces in surgery.

Objective

This paper examines the effect of surgical experience on the psychophysics of force perception and force application efficiency in MIS.

Method

A controlled experiment was conducted using a mixed design, with friction and vision as independent within-subjects factors, experience as a between-subjects factor, and applied force and detection time as dependent measures. Fourteen subjects (eight novices and six experienced surgeons) performed a simulated tissue probing task. Performance data were recorded by a custom-built force-sensing system.

Results

When friction was present, higher thresholds and longer detection times were observed for both experienced and inexperienced subjects. In all cases, experienced surgeons applied a greater force than novices, but were quicker to detect contact with tissue, resulting in higher force application efficiency.

Conclusion

Surgeons seem to have adapted to the higher threshold in haptic perception by reacting faster, even while applying more force to the tissue, keeping within the limits of safety.