Virtual reality robotic surgery warm-up improves task performance in a dry laboratory environment: a prospective randomized controlled study

Current state of virtual reality simulation in robotic surgery training: a review

BACKGROUND

Worldwide, the annual number of robotic surgical procedures continues to increase. Robotic surgical skills are unique from those used in either open or laparoscopic surgery. The acquisition of a basic robotic surgical skill set may be best accomplished in the simulation laboratory. We sought to review the current literature pertaining to the use of virtual reality (VR) simulation in the acquisition of robotic surgical skills on the da Vinci Surgical System.

MATERIALS AND METHODS

A PubMed search was conducted between December 2014 and January 2015 utilizing the following keywords: virtual reality, robotic surgery, da Vinci, da Vinci skills simulator, SimSurgery Educational Platform, Mimic dV-Trainer, and Robotic Surgery Simulator. Articles were included if they were published between 2007 and 2015, utilized VR simulation for the da Vinci Surgical System, and utilized a commercially available VR platform.

RESULTS

The initial search criteria returned 227 published articles. After all inclusion and exclusion criteria were applied, a total of 47 peer-reviewed manuscripts were included in the final review.

CONCLUSIONS

There are many benefits to utilizing VR simulation for robotic skills acquisition. Four commercially available simulators have been demonstrated to be capable of assessing robotic skill. Three of the four simulators demonstrate the ability of a VR training curriculum to improve basic robotic skills, with proficiency-based training being the most effective training style. The skills obtained on a VR training curriculum are comparable with those obtained on dry laboratory simulation. The future of VR simulation includes utilization in assessment for re-credentialing purposes, advanced procedural-based training, and as a warm-up tool prior to surgery.

Crowd-Sourced Assessment of Technical Skill: A Valid Method for Discriminating Basic Robotic Surgery Skills

BACKGROUND

A surgeon's skill in the operating room has been shown to correlate with a patient's clinical outcome. The prompt accurate assessment of surgical skill remains a challenge, in part, because expert faculty reviewers are often unavailable. By harnessing the power of large readily available crowds through the Internet, rapid, accurate, and low-cost assessments may be achieved. We hypothesized that assessments provided by crowd workers highly correlate with expert surgeons' assessments.

MATERIALS AND METHODS

A group of 49 surgeons from two hospitals performed two dry-laboratory robotic surgical skill assessment tasks. The performance of these tasks was video recorded and posted online for evaluation using Amazon Mechanical Turk. The surgical tasks in each video were graded by (n=30) varying crowd workers and (n=3) experts using a modified global evaluative assessment of Robotic Skills (GEARS) grading tool, and the mean scores were compared using Cronbach's alpha statistic.

RESULTS

GEARS evaluations from the crowd were obtained for each video and task and compared with the GEARS ratings from the expert surgeons. The crowd-based performance scores agreed with the performance assessments by experts with a Cronbach's alpha of 0.84 and 0.92 for the two tasks, respectively.

CONCLUSION

The assessment of surgical skill by crowd workers resulted in a high degree of agreement with the scores provided by expert surgeons in the evaluation of basic robotic surgical dry-laboratory tasks. Crowd responses cost less and were much faster to acquire. This study provides evidence that crowds may provide an adjunctive method for rapidly providing feedback of skills to training and practicing surgeons.

Does warming up improve surgical outcome in total hip arthroplasty?

PURPOSE

Warming up prior to surgery has been shown to enhance surgeons' performance during laparoscopic procedures. It is unknown whether or not warming up prior to total hip arthroplasty (THA) will have a similar effect on surgical outcome.

METHODS

We retrospectively evaluated the effect of warming up on the intraoperative outcome of 82 patients who underwent a primary THA with identical implants. The patients were divided equally into two groups. Group 1 (first case of the day) served as "warm-up procedure," while Group 2 (second case of the day) was the "post-warm-up procedure."

RESULTS

We found no statistically significant difference when we compared cup abduction and anteversion angles, femoral offset, postoperative LLD, stem alignment, hip center of rotation and femoral stem canal fill between the two groups (p > 0.05).

CONCLUSION

Warming up prior to performing surgery does not make a difference for primary THA when performed by an experienced surgeon. However, these results may not reflect its effect on procedures that require fine motor skills or done by an orthopedic trainee or less experienced surgeons.

Virtual reality suturing task as an objective test for robotic experience assessment

Background

We performed a pilot study using a single virtual-simulation suturing module as an objective measurement to determine functional use of the robotic system. This study will assist in designing a study for an objective, adjunctive test for use by a surgical proctor.

Methods

After IRB approval, subjects were recruited at a robotic renal surgery course to perform two attempts of the “Tubes” module without warm-up using the Da Vinci® Surgical Skills Simulator™. The overall MScore (%) from the simulator was compared among various skill levels to provide construct validity. Correlation with MScore and number of robotic cases was performed and pre-determined skill groups were tested. Nine metrics that make up the overall score were also tested via paired t test and subsequent logistic regression to determine which skills differed among experienced and novice robotic surgeons.

Results

We enrolled 38 subjects with experience ranging from 0- < 200 robotic cases. Median time to complete both tasks was less than 10 min. The MScore on the first attempt was correlated to the number of previous robotic cases (R² = 0.465; p = 0.003). MScore was different between novice and more experienced robotic surgeons on the first (44.7 vs. 63.9; p = 0.005) and second attempt (56.0 vs. 69.9; p = 0.037).

Conclusion

A single virtual simulator exercise can provide objective information in determining proficient use of the robotic surgical system.

Robot-assisted surgery: an emerging platform for human neuroscience research

Classic studies in human sensorimotor control use simplified tasks to uncover fundamental control strategies employed by the nervous system. Such simple tasks are critical for isolating specific features of motor, sensory, or cognitive processes, and for inferring causality between these features and observed behavioral changes. However, it remains unclear how these theories translate to complex sensorimotor tasks or to natural behaviors. Part of the difficulty in performing such experiments has been the lack of appropriate tools for measuring complex motor skills in real-world contexts. Robot-assisted surgery (RAS) provides an opportunity to overcome these challenges by enabling unobtrusive measurements of user behavior. In addition, a continuum of tasks with varying complexity-from simple tasks such as those in classic studies to highly complex tasks such as a surgical procedure-can be studied using RAS platforms. Finally, RAS includes a diverse participant population of inexperienced users all the way to expert surgeons. In this perspective, we illustrate how the characteristics of RAS systems make them compelling platforms to extend many theories in human neuroscience, as well as, to develop new theories altogether.

Effect of surgical case order on cataract surgery complication rates and procedure time

PURPOSE

To determine whether surgical warm-up affects cataract surgery complication rates and surgical case times.

SETTING

University of Washington Medicine Eye Institute, Harborview, Seattle, Washington, USA.

DESIGN

Retrospective case-control study.

METHODS

Patients who had phacoemulsification from June 2010 to December 2011 were consecutively reviewed. Case order for each surgeon was evaluated, comparing intraoperative complication rates and case times for attending and resident surgeons for the first case of the day (considered the warm-up case) versus subsequent cases. Simple (AMA Current Procedural Terminology code 66984) and complex (code 66982) phacoemulsification surgeries were included. Excluded were patients who had cataract surgery combined with another surgery. Pearson chi-square tests and 2-tailed independent-sample t tests were used to analyze data.

RESULTS

The study reviewed 1424 patients. Cataract surgery complication rates were not statistically different between the first cases of the day and subsequent cases (3.3% versus 4.0%) (P = .552). There was, however, a significant difference in mean case time between these groups. The mean case time for simple phacoemulsification by resident physicians was 49.45 minutes ± 19.38 (SD) for first cases and 42.27 ± 15.78 minutes for subsequent cases (P = .021) and by attending physicians, 32.54 ± 12.91 minutes and 26.69 ± 9.17 minutes, respectively (P <. 0001).

CONCLUSION

Surgical case order might not affect complication rates of cataract surgery; however, the first case of the day was longer than subsequent cases, suggesting that a preoperative warm-up exercise might decrease cataract surgery time.

FINANCIAL DISCLOSURE

Neither author has a financial or proprietary interest in any material or method mentioned.

Robotic surgical skill acquisition: What one needs to know?

Robotic surgery has been eagerly adopted by patients and surgeons alike in the field of urology, over the last decade. However, there is a lack of standardization in training curricula and accreditation guidelines to ensure surgeon competence and patient safety. Accordingly, in this review, we aim to highlight ‘who’ needs to learn ‘what’ and ‘how’, to become competent in robotic surgery. We demonstrate that both novice and experienced open surgeons require supervision and mentoring during the initial phases of robotic surgery skill acquisition. The experienced open surgeons possess domain knowledge, however, need to acquire technical knowledge under supervision (either in simulated or clinical environment) to successfully transition to robotic surgery, whereas, novice surgeons need to acquire both domain as well as technical knowledge to become competent in robotic surgery. With regard to training curricula, a variety of training programs such as academic fellowships, mini-fellowships, and mentored skill courses exist, and cater to the needs and expectations of postgraduate surgeons adequately. Fellowships provide the most comprehensive training, however, may not be suitable to all surgeon-learners secondary to the long-term time commitment. For these surgeon-learners short-term courses such as the mini-fellowships or mentored skill courses might be more apt. Lastly, with regards to credentialing uniformity in criteria regarding accreditation is lacking but earnest efforts are underway. Currently, accreditation for competence in robotic surgery is institutional specific.

A review of training research and virtual reality simulators for the da Vinci surgical system

PHENOMENON: Virtual reality simulators are the subject of several recent studies of skills training for robot-assisted surgery. Yet no consensus exists regarding what a core skill set comprises or how to measure skill performance. Defining a core skill set and relevant metrics would help surgical educators evaluate different simulators.

APPROACH

This review draws from published research to propose a core technical skill set for using the da Vinci surgeon console. Publications on three commercial simulators were used to evaluate the simulators' content addressing these skills and associated metrics.

FINDINGS

An analysis of published research suggests that a core technical skill set for operating the surgeon console includes bimanual wristed manipulation, camera control, master clutching to manage hand position, use of third instrument arm, activating energy sources, appropriate depth perception, and awareness of forces applied by instruments. Validity studies of three commercial virtual reality simulators for robot-assisted surgery suggest that all three have comparable content and metrics. However, none have comprehensive content and metrics for all core skills. INSIGHTS: Virtual reality simulation remains a promising tool to support skill training for robot-assisted surgery, yet existing commercial simulator content is inadequate for performing and assessing a comprehensive basic skill set. The results of this evaluation help identify opportunities and challenges that exist for future developments in virtual reality simulation for robot-assisted surgery. Specifically, the inclusion of educational experts in the development cycle alongside clinical and technological experts is recommended.

Effect of different warm-up strategies on simulated laparoscopy performance: a randomized controlled trial

OBJECTIVE

The objective of this trial was to assess which type of warm-up has the highest effect on virtual reality (VR) laparoscopy performance. The following warm-up strategies were applied: a hands-on exercise (group 1), a cognitive exercise (group 2), and no warm-up (control, group 3).

DESIGN

This is a 3-arm randomized controlled trial.

SETTING

The trial was conducted at the department of surgery of the University Hospital Basel in Switzerland.

PARTICIPANTS

A total of 94 participants, all laypersons without any surgical or VR experience, completed the study.

RESULTS

A total of 96 participants were randomized, 31 to group 1, 31 to group 2, and 32 to group 3. There were 2 postrandomization exclusions. In the multivariate analysis, we found no evidence that the intervention had an effect on VR performance as represented by 6 calculated subscores of accuracy, time, and path length for (1) camera manipulation and (2) hand-eye coordination combined with 2-handed maneuvers (p = 0.795). Neither the comparison of the average of the intervention groups (groups 1 and 2) vs control (group 3) nor the pairwise comparisons revealed any significant differences in VR performance, neither multivariate nor univariate. VR performance improved with increasing performance score in the cognitive exercise warm-up (iPad 3D puzzle) for accuracy, time, and path length in the camera navigation task.

CONCLUSIONS

We were unable to show an effect of the 2 tested warm-up strategies on VR performance in laypersons. We are currently designing a follow-up study including surgeons rather than laypersons with a longer warm-up exercise, which is more closely related to the final task.

Comparative analysis of the functionality of simulators of the da Vinci surgical robot

BACKGROUND

The implementation of robotic technology in minimally invasive surgery has led to the need to develop more efficient and effective training methods, as well as assessment and skill maintenance tools for surgical education. Multiple simulators and procedures are available for educational and training purposes. A need for comparative evaluations of these simulators exists to aid users in selecting an appropriate device for their purposes.

METHODS

We conducted an objective review and comparison of the design and capabilities of all dedicated simulators of the da Vinci robot, the da Vinci Skill Simulator (DVSS) (Intuitive Surgical Inc., Sunnyvale, CA, USA), dV-Trainer (dVT) (Mimic Technologies Inc., Seattle, WA, USA), and Robotic Surgery Simulator (RoSS) (Simulated Surgical Skills, LLC, Williamsville, NY, USA). This provides base specifications of the hardware and software, with an emphasis on the training capabilities of each system.

RESULTS

Each simulator contains a large number of training exercises, DVSS = 40, dVT = 65, and RoSS = 52 for skills development. All three offer 3D visual images but use different display technologies. The DVSS leverages the real robotic surgeon's console to provide visualization, hand controls, and foot pedals. The dVT and RoSS created simulated versions of all of these control systems. They include systems management services which allow instructors to collect, export, and analyze the scores of students using the simulators.

CONCLUSIONS

This study is the first to provide comparative information of the three simulators functional capabilities with an emphasis on their educational skills. They offer unique advantages and capabilities in training robotic surgeons. Each device has been the subject of multiple validation experiments which have been published in the literature. But those do not provide specific details on the capabilities of the simulators which are necessary for an understanding sufficient to select the one best suited for an organization's needs.

Telementoring in education of laparoscopic surgeons: An emerging technology

Laparoscopy, minimally invasive and minimal access surgery with more surgeons performing these advanced procedures. We highlight in the review several key emerging technologies such as the telementoring and virtual reality simulators, that provide a solid ground for delivering surgical education to rural area and allow young surgeons a safety net and confidence while operating on a newly learned technique.

Using virtual reality to maintain surgical skills during periods of robotic surgery inactivity

Periodic practice is needed for newly trained robotic surgeons to maintain skills during periods of robotic inactivity. The current study was performed to determine whether virtual robotic skill maintenance can serve as an adequate substitute for practice on a surgical robot. Eleven surgical residents with no prior robotic training were trained to a level of robotic proficiency with inanimate models, including a needle driving pad, a running suture pad, and ring placement on a rocking peg board. After reaching proficiency, each resident was tested on a complex tissue closure task. For the next 8 weeks, the only robotic activity was biweekly virtual robotic skills maintenance. After 8 weeks, the residents performed the tissue closure task twice with the robot, followed by evaluation on the inanimate models used to reach proficiency. Repeated-measures statistical analyses were used to compare between the three tissue closure trials and between the final test at week 0 and the evaluation at week 8 for the other inanimate models. Time to complete the tissue closure task was more than 20 % lower for the second evaluation at 8 weeks than for the other two trials (p < 0.05). Residents maintained their skills for needle driving, but times for suture running and rocking peg board increased by more than 20 % at 8 weeks (p < 0.01). Virtual practice shows promise for maintaining robotic skills. Following a warm-up period, some skills may actually improve with biweekly virtual practice, but skill retention is selective, so further improvements are needed.

Effects of robotic manipulators on movements of novices and surgeons

BACKGROUND

Robot-assisted surgery is widely adopted for many procedures but has not realized its full potential to date. Based on human motor control theories, the authors hypothesized that the dynamics of the master manipulators impose challenges on the motor system of the user and may impair performance and slow down learning. Although studies have shown that robotic outcomes are correlated with the case experience of the surgeon, the relative contribution of cognitive versus motor skill is unknown. This study quantified the effects of da Vinci Si master manipulator dynamics on movements of novice users and experienced surgeons and suggests possible implications for training and robot design.

METHODS

In the reported study, six experienced robotic surgeons and ten novice nonmedical users performed movements under two conditions: teleoperation of a da Vinci Si Surgical system and freehand. A linear mixed model was applied to nine kinematic metrics (including endpoint error, movement time, peak speed, initial jerk, and deviation from a straight line) to assess the effects of teleoperation and expertise. To assess learning effects, t tests between the first and last movements of each type were used.

RESULTS

All the users moved slower during teleoperation than during freehand movements (F(1,9343) = 345; p < 0.001). The experienced surgeons had smaller errors than the novices (F(1,14) = 36.8; p < 0.001). The straightness of movements depended on their direction (F(7,9343) = 117; p < 0.001). Learning effects were observed in all conditions. Novice users first learned the task and then the dynamics of the manipulator.

CONCLUSIONS

The findings showed differences between the novices and the experienced surgeons for extremely simple point-to-point movements. The study demonstrated that manipulator dynamics affect user movements, suggesting that these dynamics could be improved in future robot designs. The authors showed the partial adaptation of novice users to the dynamics. Future studies are needed to evaluate whether it will be beneficial to include early training sessions dedicated to learning the dynamics of the manipulator.

Training in robotics: The learning curve and contemporary concepts in training

Objective

To define the learning curve of robot-assisted laparoscopic surgery for prostatectomy (RALP) and upper tract procedures, and show the differences between the classical approach to training and the new concept of parallel learning.

Methods

This mini-review is based on the results of a Medline search using the keywords ‘da Vinci’, ‘robot-assisted laparoscopic surgery’, ‘training’, ‘teaching’ and ‘learning curve’.

Results

For RALP and robot-assisted upper tract surgery, a learning curve of 8–150 procedures is quoted, with most articles proposing that 30–40 cases are needed to carry out the procedure safely. There is no consensus about which endpoints should be measured. In the traditional proctored training model, the surgeon learns the procedure linearly, following the sequential order of the surgical steps. A more recent approach is to specify the relative difficulty of each step and to train the surgeon simultaneously in several steps of equal difficulty. The entire procedure is only performed after all the steps are mastered in a timely manner. Recently, a ‘warm-up’ before robotic surgery has been shown to be beneficial for successful surgery in the operating room.

Conclusion

There is no clear definition of the duration of the effective learning curve for RALP and robotic upper tract surgery. The concept of stepwise, parallel learning has the potential to accelerate the learning process and to make sure that initial cases are not too long. It can also be assumed that a preoperative ‘warm up’ could help significantly to improve the progress of the trainee.