Comparison of cadaveric and isomorphic virtual haptic simulation in temporal bone training

Fully immersive virtual reality for skull-base surgery: surgical training and beyond

PURPOSE

A virtual reality (VR) system, where surgeons can practice procedures on virtual anatomies, is a scalable and cost-effective alternative to cadaveric training. The fully digitized virtual surgeries can also be used to assess the surgeon's skills using measurements that are otherwise hard to collect in reality. Thus, we present the Fully Immersive Virtual Reality System (FIVRS) for skull-base surgery, which combines surgical simulation software with a high-fidelity hardware setup.

METHODS

FIVRS allows surgeons to follow normal clinical workflows inside the VR environment. FIVRS uses advanced rendering designs and drilling algorithms for realistic bone ablation. A head-mounted display with ergonomics similar to that of surgical microscopes is used to improve immersiveness. Extensive multi-modal data are recorded for post-analysis, including eye gaze, motion, force, and video of the surgery. A user-friendly interface is also designed to ease the learning curve of using FIVRS.

RESULTS

We present results from a user study involving surgeons with various levels of expertise. The preliminary data recorded by FIVRS differentiate between participants with different levels of expertise, promising future research on automatic skill assessment. Furthermore, informal feedback from the study participants about the system's intuitiveness and immersiveness was positive.

CONCLUSION

We present FIVRS, a fully immersive VR system for skull-base surgery. FIVRS features a realistic software simulation coupled with modern hardware for improved realism. The system is completely open source and provides feature-rich data in an industry-standard format.

What is the Current State of Extended Reality Use in Otolaryngology Training? A Scoping Review

OBJECTIVE

To map current literature on the educational use of extended reality (XR) in Otolaryngology-Head and Neck Surgery (OHNS) to inform teaching and research.

STUDY DESIGN

Scoping Review.

METHODS

A scoping review was conducted, identifying literature through MEDLINE, Ovid Embase, and Web of Science databases. Findings were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping review checklist. Studies were included if they involved OHNS trainees or medical students who used XR for an educational purpose in OHNS. XR was defined as: fully-immersive virtual reality (VR) using head-mounted displays (HMDs), non-immersive and semi-immersive VR, augmented reality (AR), or mixed reality (MR). Data on device use were extracted, and educational outcomes were analyzed according to Kirkpatrick's evaluation framework.

RESULTS

Of the 1,434 unique abstracts identified, 40 articles were included. All articles reported on VR; none discussed AR or MR. Twenty-nine articles were categorized as semi-immersive, none used occlusive HMDs therefore, none met modern definitions of immersive VR. Most studies (29 of 40) targeted temporal bone surgery. Using the Kirkpatrick four-level evaluation model, all studies were limited to level-1 (learner reaction) or level-2 (knowledge or skill performance).

CONCLUSIONS

Current educational applications of XR in OHNS are limited to VR, do not fully immerse participants and do not assess higher-level learning outcomes. The educational OHNS community would benefit from a shared definition for VR technology, assessment of skills transfer (level-3 and higher), and deliberate testing of AR, MR, and procedures beyond temporal bone surgery. Laryngoscope, 133:227-234, 2023.

An objective assessment for bone drilling: A pilot study on vertical drilling

The purpose of this study is to propose a quantitative assessment scheme to help with surgical bone drilling training. This pilot study gathered and compared motion and force data from expert surgeons (n = 3) and novice residents (n = 6). The experiment used three-dimensional printed bone simulants of young bone (YB) and osteoporotic bone (OB), and drilling overshoot, time, and force were measured. There was no statistically significant difference in overshoot between the two groups (p = 0.217 for YB and 0.215 for OB). The results, however, show that the experts took less time (mean = 4.01 s) than the novices (mean = 9.98 s), with a statistical difference (p = 0.003 for YB and 0.0001 for OB). In addition, the expert group performed more consistently than the novices. The force analysis further revealed that experts used a higher force to drill the first cortical section and a noticeably lower force in the second cortex to control the overshoot (approximate reduction of 5.5 N). Finally, when drilling time and overshoot distance were combined, the motion data distinguished the skill gap between expert and novice drilling; the force data provided insight into the drilling mechanism and performance outcomes. This study lays the groundwork for a data-driven training scheme to prepare novice residents for clinical practice.

Developing an Evidence-Based Surgical Curriculum: Learning from a Randomized Controlled Trial of Surgical Rehearsal in Virtual Reality

BACKGROUND

Surgical rehearsal - patient-specific preoperative surgical practice - can be provided by virtual reality simulation. This study investigated the effect of surgical rehearsal on cortical mastoidectomy performance and procedure duration.

METHODS

University students (n=40) were randomized evenly into a rehearsal and control group. After watching a video tutorial on cortical mastoidectomy, participants completed the procedure on a virtual reality simulator as a pre-test. Participants completed a further 8 cortical mastoidectomies on the virtual reality simulator as training before drilling two 3-dimensional (3D) printed temporal bones. The rehearsal group received 3D printed bones they had previously operated on in virtual reality, while the control group received 2 new bones. Cortical mastoidectomy was assessed by 3 blinded graders using the Melbourne Mastoidectomy Scale.

RESULTS

There was high interrater reliability between the 3 graders (intraclass correlation coefficient, r=0.8533, P < .0001). There was no difference in the mean surgical performance on the two 3D printed bones between the control and rehearsal groups (P=.2791). There was no significant difference in the mean procedure duration between the control and rehearsal groups for both 3D printed bones (P=.8709). However, there was a significant decrease in procedure duration between the first and second 3D printed bones (P < .0001).

CONCLUSION

In this study, patient-specific virtual reality rehearsal provided no additional advantage to cortical mastoidectomy performance by novice operators compared to generic practice on a virtual reality simulator. Further, virtual reality training did not improve cortical mastoidectomy performance on 3D printed bones, highlighting the impact of anatomical diversity and changing operating modalities on the acquisition of new surgical skills.

Comparison of Summative Temporal Bone Dissection Scales Demonstrate Equivalence

Introduction  Temporal bone surgery is a unique and complicated surgical skill that requires extensive training. There is an educational requirement to maximize trainee experience and provide effective feedback.

Objective  We evaluate three temporal bone dissection scales for efficacy, reliability, and accuracy in identifying resident skill during temporal bone surgery.

Methods  Residents of various skill levels performed a mastoidectomy with posterior tympanotomy on identic 3D-printed temporal bone models. Four blinded otologic surgeons evaluated each specimen at two separate intervals using three separate dissection scales: the Welling Scale (WS), the Iowa Temporal Bone Assessment Tool (ITBAT), and the CanadaWest Scale (CWS). Scores from each scale were compared in their ability to accurately separate residents by skill level, inter- and intrarater reliability, and efficiency in application.

Results  Nineteen residents from 9 postgraduate programs participated. Assessment was clustered into junior (postgraduate year or PGY 1, 2), intermediate (PGY 3) and senior resident (PGY 4, 5) cohorts. Analysis of variance (ANOVA) found significant differences between cohort performance ( p  < 0.05) for all 3 scales considering the PGY level and the subjective account of temporal bone surgical experience. The inter-rater reliability was consistent across each scale. The intrarater reliability was comparable between the CWS (0.711) and the WS (0.713), but not the ITBAT (0.289). Time (in seconds) to complete scoring for each scale was also comparable between the CWS (42.7 ± 16.8), the WS (76.6 ± 14.5), and the ITBAT (105.6 ± 38.9).

Conclusion  All three scales demonstrated construct validity and consistency in performance, and consideration should be given to judicious use in training.

Simulation for skills training in neurosurgery: a systematic review, meta-analysis, and analysis of progressive scholarly acceptance

At a time of significant global unrest and uncertainty surrounding how the delivery of clinical training will unfold over the coming years, we offer a systematic review, meta-analysis, and bibliometric analysis of global studies showing the crucial role simulation will play in training. Our aim was to determine the types of simulators in use, their effectiveness in improving clinical skills, and whether we have reached a point of global acceptance. A PRISMA-guided global systematic review of the neurosurgical simulators available, a meta-analysis of their effectiveness, and an extended analysis of their progressive scholarly acceptance on studies meeting our inclusion criteria of simulation in neurosurgical education were performed. Improvement in procedural knowledge and technical skills was evaluated. Of the identified 7405 studies, 56 studies met the inclusion criteria, collectively reporting 50 simulator types ranging from cadaveric, low-fidelity, and part-task to virtual reality (VR) simulators. In all, 32 studies were included in the meta-analysis, including 7 randomised controlled trials. A random effects, ratio of means effects measure quantified statistically significant improvement in procedural knowledge by 50.2% (ES 0.502; CI 0.355; 0.649, p < 0.001), technical skill including accuracy by 32.5% (ES 0.325; CI - 0.482; - 0.167, p < 0.001), and speed by 25% (ES - 0.25, CI - 0.399; - 0.107, p < 0.001). The initial number of VR studies (n = 91) was approximately double the number of refining studies (n = 45) indicating it is yet to reach progressive scholarly acceptance. There is strong evidence for a beneficial impact of adopting simulation in the improvement of procedural knowledge and technical skill. We show a growing trend towards the adoption of neurosurgical simulators, although we have not fully gained progressive scholarly acceptance for VR-based simulation technologies in neurosurgical education.

Patient-specific Virtual Temporal Bone Simulation Based on Clinical Cone-beam Computed Tomography

OBJECTIVES

Patient-specific surgical simulation allows presurgical planning through three-dimensional (3D) visualization and virtual rehearsal. Virtual reality simulation for otologic surgery can be based on high-resolution cone-beam computed tomography (CBCT). This study aimed to evaluate clinicians' experience with patient-specific simulation of mastoid surgery.

METHODS

Prospective, multi-institutional study. Preoperative temporal bone CBCT scans of patients undergoing cochlear implantation (CI) were retrospectively obtained. Automated processing and segmentation routines were used. Otologic surgeons performed a complete mastoidectomy with facial recess approach on the patient-specific virtual cases in the institution's temporal bone simulator. Participants completed surveys regarding the perceived accuracy and utility of the simulation.

RESULTS

Twenty-two clinical CBCTs were obtained. Four attending otologic surgeons and 5 otolaryngology trainees enrolled in the study. The mean number of simulations completed by each participant was 16.5 (range 3-22). "Overall experience" and "usefulness for presurgical planning" were rated as "good," "very good," or "excellent" in 84.6% and 71.6% of the simulations, respectively. In 10.7% of simulations, the surgeon reported to have gained a significantly greater understanding of the patient's anatomy compared to standard imaging. Participants were able to better appreciate subtle anatomic findings after using the simulator for 60.4% of cases. Variable CBCT acquisition quality was the most reported limitation.

CONCLUSION

Patient-specific simulation using preoperative CBCT is feasible and may provide valuable insights prior to otologic surgery. Establishing a CBCT acquisition protocol that allows for consistent segmentation will be essential for reliable surgical simulation.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:1855-1862, 2021.

Virtual Reality and Augmented Reality in Plastic Surgery: A Review

Recently, virtual reality (VR) and augmented reality (AR) have received increasing attention, with the development of VR/AR devices such as head-mounted displays, haptic devices, and AR glasses. Medicine is considered to be one of the most effective applications of VR/AR. In this article, we describe a systematic literature review conducted to investigate the state-of-the-art VR/AR technology relevant to plastic surgery. The 35 studies that were ultimately selected were categorized into 3 representative topics: VR/AR-based preoperative planning, navigation, and training. In addition, future trends of VR/AR technology associated with plastic surgery and related fields are discussed.