Training otologic surgical skills through simulation-moving toward validation: a pilot study and lessons learned

Use of a Virtual Reality Simulator for Tendon Repair Training: Randomized Controlled Trial

Background

Virtual reality (VR) simulators have become widespread tools for training medical students and residents in medical schools. Students using VR simulators are provided with a 3D human model to observe the details by using multiple senses and they can participate in an environment that is similar to reality.

Objective

The aim of this study was to promote a new approach consisting of a shared and independent study platform for medical orthopedic students, to compare traditional tendon repair training with VR simulation of tendon repair, and to evaluate future applications of VR simulation in the academic medical field.

Methods

In this study, 121 participants were randomly allocated to VR or control groups. The participants in the VR group studied the tendon repair technique via the VR simulator, while the control group followed traditional tendon repair teaching methods. The final assessment for the medical students involved performing tendon repair with the “Kessler tendon repair with 2 interrupted tendon repair knots” (KS) method and the “Bunnell tendon repair with figure 8 tendon repair” (BS) method on a synthetic model. The operative performance was evaluated using the global rating scale.

Results

Of the 121 participants, 117 participants finished the assessment and 4 participants were lost to follow-up. The overall performance (a total score of 35) of the VR group using the KS method and the BS method was significantly higher (P<.001) than that of the control group. Thus, participants who received VR simulator training had a significantly higher score on the global rating scale than those who received traditional tendon repair training (P<.001).

Conclusions

Our study shows that compared with the traditional tendon repair method, the VR simulator for learning tendon suturing resulted in a significant improvement of the medical students in the time in motion, flow of operation, and knowledge of the procedure. Therefore, VR simulator development in the future would most likely be beneficial for medical education and clinical practice.

Trial Registration

Chinese Clinical Trial Registry ChiCTR2100046648; http://www.chictr.org.cn/hvshowproject.aspx?id=90180

Exploration of temporal bone anatomy using mixed reality (HoloLens): development of a mixed reality anatomy teaching resource prototype

Mixed reality (MR), a technology which supplements the real world with virtual objects, is increasingly becoming available as a teaching tool in medical education. The Microsoft HoloLens device allows operators to experience MR using a head-mounted device without interfering with their physical reality, stimulating a realistic learning experience using virtual objects. This project aimed to develop a MR anatomy teaching application with HoloLens for exploring the anatomy of the temporal bone. The educational application was developed from a multidisciplinary collaboration between undergraduate and postgraduate students across several academic disciplines with Medtronic, a medical technology company. 3D anatomical models were built using ZBrush and Blender, while the HoloLens1 application was developed using Windows 10, Visual Studio 2017, Unity and Mixed Reality Toolkit (MRTK). Modules developed within the application included a basic HoloLens tutorial, a virtual temporal bone with surgical anatomy landmarks and free drilling of the temporal bone. The basic tutorial allows the operator to adapt to the MR environment prior to exploring the anatomical landmarks of the 3D temporal bone. The free drilling of the temporal bone using vertex displacement and texture stretching replicates a real-time bone drilling experience and allows the operator to explore the anatomical relationship between different otological structures.

Elements of virtual temporal bone surgery: Manipulandum format may be more important to surgeons than haptic device force capabilities

Background

Temporal bone simulations are critiqued for poor drill‐bone interaction. This project appraises the import of increasing haptic device and manipulandum fidelity on the perceived realism of drilling a virtual temporal bone.

Virtual surgical contact forces rely on haptic device fidelity and are transmitted through a manipulandum. With identical software, both device hardware and manipulandum may each contribute to realism. We compare the three degrees of freedom (DOF), 3N Geomagic Touch (3D Systems, SC) to a 6DOF, 5.5N HD² (Quanser, ON) with the both standard (“HD²–Standard”) and in‐house customized otic drill manipulandum (“HD²–Modified”).

Methods

Six otologic surgeons performed three virtual mastoidectomy surgeries on a temporal bone surgical simulator. The HD² manipulandum was modified for attached otic drill with gravity compensation and requisite mechanical modifications. Surgeons, in random order, performed the dissection with the different hardware platforms.

Results

Two‐tailed t‐tests demonstrate that for the acoustic properties of each simulation, the HD²–Modified manipulandum was favored (p ≤ 0.0004). For overall similarity of bone, both HD²–Standard (p ≤ 0.05) HD²–Modified (p ≤ 0.03)) were favored over the Geomagic; however they were not appreciably different when directly compared to each other. There was no preference for increasing haptic device fidelity in virtual drill bone interaction.

In forced rank, users favored the HD²–Modified in osseus, vibrational and overall realism, as well as being preferred for education and preoperative rehearsal (p ≤ 0.0164).

Conclusion

Increasing manipulandum realism was favored. However surprisingly, there was no preference for increased device fidelity, illustrating incremental stiffness had nominal impact. There may be a ceiling to drill bone interaction in virtual haptic simulation.

Level of Evidence

2b.

Chicken thigh microvascular training model improves resident surgical skills

Objectives

Microsurgical techniques are essential for vessel anastomosis in free flap reconstructive surgery. However, teaching these skills intraoperatively is difficult. The chicken thigh microvascular model is a high‐fidelity model that has been previously validated to differentiate between skill levels of surgeons. This study aims to determine if this model objectively improves microsurgical skills.

Study Design

Validation study

Methods

Thirteen residents were given a tutorial on microvascular anastomosis and asked to perform anastomoses on the microvascular model. Anastomoses were video‐recorded and the time required for trainees to complete the first stitch of their first anastomosis was compared to the time required for the first stitch of their last anastomosis. Comparison of first and last stitch times was completed using a paired student t‐test. All participants completed a survey regarding their experience with the simulator.

Results

There was a statistically significant decrease between the time required for the first stitch (235 s, 95%CI 198–272 s) compared to last stitch (120 s, 95%CI 92–149 s), and an average 48.7% (115 s) decrease in time (p < 0.001). Junior (PGY 2/3) and senior (PGY 4/5) residents had similar decreases in time, 49.1% and 48.21%, respectively. One hundred percent of residents felt they improved during the session and 92% of residents agreed or strongly agreed that their final stitch was better than their last stitch. All residents agreed or strongly agreed that the simulation is realistic, effective in teaching the procedure, and would translate to improved intraoperative performance.

Conclusions

The chicken thigh model demonstrates objective improvements in resident microvascular surgical skills.

Level of Evidence

NA

Cognitive Load in Mastoidectomy Skills Training: Virtual Reality Simulation and Traditional Dissection Compared

OBJECTIVE

The cognitive load (CL) theoretical framework suggests that working memory is limited, which has implications for learning and skills acquisition. Complex learning situations such as surgical skills training can potentially induce a cognitive overload, inhibiting learning. This study aims to compare CL in traditional cadaveric dissection training and virtual reality (VR) simulation training of mastoidectomy.

DESIGN

A prospective, crossover study. Participants performed cadaveric dissection before VR simulation of the procedure or vice versa. CL was estimated by secondary-task reaction time testing at baseline and during the procedure in both training modalities.

SETTING

The national Danish temporal bone course.

PARTICIPANTS

A total of 40 novice otorhinolaryngology residents.

RESULTS

Reaction time was increased by 20% in VR simulation training and 55% in cadaveric dissection training of mastoidectomy compared with baseline measurements. Traditional dissection training increased CL significantly more than VR simulation training (p < 0.001).

CONCLUSIONS

VR simulation training imposed a lower CL than traditional cadaveric dissection training of mastoidectomy. Learning complex surgical skills can be a challenge for the novice and mastoidectomy skills training could potentially be optimized by employing VR simulation training first because of the lower CL. Traditional dissection training could then be used to supplement skills training after basic competencies have been acquired in the VR simulation.

The effect of self-directed virtual reality simulation on dissection training performance in mastoidectomy

OBJECTIVES/HYPOTHESIS

To establish the effect of self-directed virtual reality (VR) simulation training on cadaveric dissection training performance in mastoidectomy and the transferability of skills acquired in VR simulation training to the cadaveric dissection training setting.

STUDY DESIGN

Prospective study.

METHODS

Two cohorts of 20 novice otorhinolaryngology residents received either self-directed VR simulation training before cadaveric dissection training or vice versa. Cadaveric and VR simulation performances were assessed using final-product analysis with three blinded expert raters.

RESULTS

The group receiving VR simulation training before cadaveric dissection had a mean final-product score of 14.9 (95 % confidence interval [CI] [12.9-16.9]) compared with 9.8 (95% CI [8.4-11.1]) in the group not receiving VR simulation training before cadaveric dissection. This 52% increase in performance was statistically significantly (P < 0.0001). A single dissection mastoidectomy did not increase VR simulation performance (P = 0.22).

CONCLUSIONS

Two hours of self-directed VR simulation training was effective in increasing cadaveric dissection mastoidectomy performance and suggests that mastoidectomy skills are transferable from VR simulation to the traditional dissection setting. Virtual reality simulation training can therefore be employed to optimize training, and can spare the use of donated material and instructional resources for more advanced training after basic competencies have been acquired in the VR simulation environment.

LEVEL OF EVIDENCE

NA. Laryngoscope, 126:1883-1888, 2016.

Virtual reality training for improving the skills needed for performing surgery of the ear, nose or throat

BACKGROUND

Virtual reality simulation uses computer-generated imagery to present a simulated training environment for learners. This review seeks to examine whether there is evidence to support the introduction of virtual reality surgical simulation into ear, nose and throat surgical training programmes.

OBJECTIVES

1. To assess whether surgeons undertaking virtual reality simulation-based training achieve surgical ('patient') outcomes that are at least as good as, or better than, those achieved through conventional training methods.2. To assess whether there is evidence from either the operating theatre, or from controlled (simulation centre-based) environments, that virtual reality-based surgical training leads to surgical skills that are comparable to, or better than, those achieved through conventional training.

SEARCH METHODS

The Cochrane Ear, Nose and Throat Disorders Group (CENTDG) Trials Search Co-ordinator searched the CENTDG Trials Register; Central Register of Controlled Trials (CENTRAL 2015, Issue 6); PubMed; EMBASE; ERIC; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 27 July 2015.

SELECTION CRITERIA

We included all randomised controlled trials and controlled trials comparing virtual reality training and any other method of training in ear, nose or throat surgery.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by The Cochrane Collaboration. We evaluated both technical and non-technical aspects of skill competency.

MAIN RESULTS

We included nine studies involving 210 participants. Out of these, four studies (involving 61 residents) assessed technical skills in the operating theatre (primary outcomes). Five studies (comprising 149 residents and medical students) assessed technical skills in controlled environments (secondary outcomes). The majority of the trials were at high risk of bias. We assessed the GRADE quality of evidence for most outcomes across studies as 'low'. Operating theatre environment (primary outcomes) In the operating theatre, there were no studies that examined two of three primary outcomes: real world patient outcomes and acquisition of non-technical skills. The third primary outcome (technical skills in the operating theatre) was evaluated in two studies comparing virtual reality endoscopic sinus surgery training with conventional training. In one study, psychomotor skill (which relates to operative technique or the physical co-ordination associated with instrument handling) was assessed on a 10-point scale. A second study evaluated the procedural outcome of time-on-task. The virtual reality group performance was significantly better, with a better psychomotor score (mean difference (MD) 1.66, 95% CI 0.52 to 2.81; 10-point scale) and a shorter time taken to complete the operation (MD -5.50 minutes, 95% CI -9.97 to -1.03). Controlled training environments (secondary outcomes) In a controlled environment five studies evaluated the technical skills of surgical trainees (one study) and medical students (three studies). One study was excluded from the analysis. Surgical trainees: One study (80 participants) evaluated the technical performance of surgical trainees during temporal bone surgery, where the outcome was the quality of the final dissection. There was no difference in the end-product scores between virtual reality and cadaveric temporal bone training. Medical students: Two other studies (40 participants) evaluated technical skills achieved by medical students in the temporal bone laboratory. Learners' knowledge of the flow of the operative procedure (procedural score) was better after virtual reality than conventional training (SMD 1.11, 95% CI 0.44 to 1.79). There was also a significant difference in end-product score between the virtual reality and conventional training groups (SMD 2.60, 95% CI 1.71 to 3.49). One study (17 participants) revealed that medical students acquired anatomical knowledge (on a scale of 0 to 10) better during virtual reality than during conventional training (MD 4.3, 95% CI 2.05 to 6.55). No studies in a controlled training environment assessed non-technical skills.

AUTHORS' CONCLUSIONS

There is limited evidence to support the inclusion of virtual reality surgical simulation into surgical training programmes, on the basis that it can allow trainees to develop technical skills that are at least as good as those achieved through conventional training. Further investigations are required to determine whether virtual reality training is associated with better real world outcomes for patients and the development of non-technical skills. Virtual reality simulation may be considered as an additional learning tool for medical students.

Cadaveric temporal bone dissection: is it obsolete today?

Introduction Traditionally, surgical training in otology, is imparted by dissecting harvested human cadaveric temporal bones. However, maintenance of a cadaveric temporal bone laboratory is expensive and carries risk of exposure to infection. In recent times, other modalities of training are gaining ground and are likely to eventually replace cadaveric temporal bone dissection altogether.

Objectives Other alternative methods of training are emerging. New technology like simulation and virtual reality as high-fidelity, safer alternatives, are making rapid strides as teaching tools. Other options are the use of animal temporal bones as teaching tools. The advantages of these are compared.

Data Synthesis None of these modalities can replicate the innumerable anatomical variations which are a characteristic feature of the human temporal bone. A novice surgeon not only needs exposure to surgical anatomy and it's variations but also needs to develop hand-eye coordination skills to gain expertise.

Conclusion Deliberate practice on human cadaveric temporal bones only, will confer both mastery in anatomy and surgical technique. The human cadaveric temporal bone is ideal simulator for training in otology.

Translating the simulation of procedural drilling techniques for interactive neurosurgical training

BACKGROUND

Through previous efforts we have developed a fully virtual environment to provide procedural training of otologic surgical technique. The virtual environment is based on high-resolution volumetric data of the regional anatomy. These volumetric data help drive an interactive multisensory, ie, visual (stereo), aural (stereo), and tactile, simulation environment. Subsequently, we have extended our efforts to support the training of neurosurgical procedural technique as part of the Congress of Neurological Surgeons simulation initiative.

OBJECTIVE

To deliberately study the integration of simulation technologies into the neurosurgical curriculum and to determine their efficacy in teaching minimally invasive cranial and skull base approaches.

METHODS

We discuss issues of biofidelity and our methods to provide objective, quantitative and automated assessment for the residents.

RESULTS

We conclude with a discussion of our experiences by reporting preliminary formative pilot studies and proposed approaches to take the simulation to the next level through additional validation studies.

CONCLUSION

We have presented our efforts to translate an otologic simulation environment for use in the neurosurgical curriculum. We have demonstrated the initial proof of principles and define the steps to integrate and validate the system as an adjuvant to the neurosurgical curriculum.

Translating the Simulation of Procedural Drilling Techniques for Interactive Neurosurgical Training

BACKGROUND:

Through previous efforts we have developed a fully virtual environment to provide procedural training of otologic surgical technique. The virtual environment is based on high-resolution volumetric data of the regional anatomy. These volumetric data help drive an interactive multisensory, ie, visual (stereo), aural (stereo), and tactile, simulation environment. Subsequently, we have extended our efforts to support the training of neurosurgical procedural technique as part of the Congress of Neurological Surgeons simulation initiative.

OBJECTIVE:

To deliberately study the integration of simulation technologies into the neurosurgical curriculum and to determine their efficacy in teaching minimally invasive cranial and skull base approaches.

METHODS:

We discuss issues of biofidelity and our methods to provide objective, quantitative and automated assessment for the residents.

RESULTS:

We conclude with a discussion of our experiences by reporting preliminary formative pilot studies and proposed approaches to take the simulation to the next level through additional validation studies.

CONCLUSION:

We have presented our efforts to translate an otologic simulation environment for use in the neurosurgical curriculum. We have demonstrated the initial proof of principles and define the steps to integrate and validate the system as an adjuvant to the neurosurgical curriculum.

Training and simulation in otolaryngology

This article focuses on key issues surrounding the needs and application of simulation technologies for technical skills training in otolaryngology. The discussion includes an overview of key topics in training and learning, the application of these issues in simulation environments, and the subsequent applications of these simulation environments to otolaryngology. Examples of past applications are presented, with discussion of how the interplay of cultural changes in surgical training in general along with the rapid advancements in technology have shaped and influenced their adoption and adaptation. The authors conclude with emerging trends and potential influences advanced simulation and training will have on technical skills training in otolaryngology.

Improving temporal bone dissection using self-directed virtual reality simulation: results of a randomized blinded control trial

OBJECTIVE

A significant benefit of virtual reality (VR) simulation is the ability to provide self-direct learning for trainees. This study aims to determine whether there are any differences in performance of cadaver temporal bone dissections between novices who received traditional teaching methods and those who received unsupervised self-directed learning in a VR temporal bone simulator.

STUDY DESIGN

Randomized blinded control trial.

SETTING

Royal Victorian Eye and Ear Hospital.

SUBJECTS

Twenty novice trainees.

METHODS

After receiving an hour lecture, participants were randomized into 2 groups to receive an additional 2 hours of training via traditional teaching methods or self-directed learning using a VR simulator with automated guidance. The simulation environment presented participants with structured training tasks, which were accompanied by real-time computer-generated feedback as well as real operative videos and photos. After the training, trainees were asked to perform a cortical mastoidectomy on a cadaveric temporal bone. The dissection was videotaped and assessed by 3 otologists blinded to participants' teaching group.

RESULTS

The overall performance scores of the simulator-based training group were significantly higher than those of the traditional training group (67% vs 29%; P < .001), with an intraclass correlation coefficient of 0.93, indicating excellent interrater reliability. Using other assessments of performance, such as injury size, the VR simulator-based training group also performed better than the traditional group.

CONCLUSIONS

This study indicates that self-directed learning on VR simulators can be used to improve performance on cadaver dissection in novice trainees compared with traditional teaching methods alone.

Creating a cross-institutional grading scale for temporal bone dissection

OBJECTIVES/HYPOTHESIS

There is increasing interest in objective assessment of surgeon competence. In the field of otolaryngology, several surgical training programs, including The Ohio State University, the University of Toronto, and Stanford University, have pursued standardized criteria to rate their trainees' performance in the initial steps of temporal bone dissection (complete mastoidectomy with facial recess approach). Although these assessment metrics require the completion of similar basic components integral to successful temporal bone dissection, certain listed criteria are unique to each institution. Our aim was to establish a more standardized set of criteria that can be used across different institutions to objectively assess temporal bone dissection. We translated these new criteria into automated metrics in our temporal bone dissection simulator to achieve even more objective grading of temporal bone dissections.

STUDY DESIGN

Cross-sectional study/survey.

METHODS

The temporal bone assessment criteria developed by each of the three aforementioned institutions were compiled into an all-encompassing scale. This compilation was sent out as an online survey to members of the American Neurotology Society and American Otological Society with instructions to rate the importance of each criterion.

RESULTS

Criteria that were ranked by >70% of respondents as either "very important" or "important" were used to create the new, cross-institutional scale for the objective assessment of temporal bone dissection.

CONCLUSIONS

The new assessment scale and its eventual incorporation into the temporal bone surgical simulator will enhance the objectivity of currently existing methods to evaluate surgical performance across different institutions.