Comparison of Experts and Residents Performing a Complex Procedure in a Temporal Bone Surgery Simulator

Evaluating Learning Curves in Virtual Reality Cortical Mastoidectomy Training Across Expertise Levels

HYPOTHESIS

Virtual reality (VR) simulation has been established as an effective method of supplementing traditional surgical training. Learning curves can analyze skill acquisition over time in VR settings. Although previous studies explored learning curves of mastoidectomy performances on single specimen, this study analyzed learning curves on anatomically different virtual temporal bones across three expertise levels (novice, intermediate, and expert).

METHODS

Thirty participants were divided into three groups: 10 medical students (novice), 10 ear, nose and throat (ENT) registrars (intermediate), and 10 senior ear surgeons (expert). They performed mastoidectomy on eight anatomically different temporal bones on the University of Melbourne Temporal Bone Surgery Simulator. A blinded senior ENT surgeon assessed the final products of the dissections using the Melbourne Mastoidectomy Scale (MMS). Learning curves of MMS scores, number of strokes, average force, drilling time, and total time were compared between groups using Friedman tests. Within-group analyses were conducted with Wilcoxon signed-rank tests.

RESULTS

All performance metrics showed significant differences across all groups. Only comparison between intermediate and expert groups for average force was not significant. Within-group analyses showed significant differences in expert group for total and drilling time, intermediate group for average force, and novice group for total time. Individual learning curves of intermediate group demonstrated varied learning behavior.

CONCLUSIONS

Trainee performance was not seen to reach the level of experts after eight repetitions on anatomically different specimens. Enhancing training with individualized feedback and increased repetitions may optimize skills acquisition.

Automated Technical Skill and Performance Assessment in Otology and Neurotology: A Scoping Review

OBJECTIVES/HYPOTHESIS

This scoping review aims to provide an overview of existing semi-automated and fully automated methods for technical skill and performance assessment in otologic and neurotologic procedures.

STUDY DESIGN

Scoping review.

DATABASES REVIEWED

Ovid MEDLINE (PubMed), Ovid EMBASE, Web of Science Core Collection, and IEEE Xplor Digital Library.

METHODS

A literature search was conducted according to PRISMA-ScR. Included studies were full-text articles that detailed an automated method of technical skill and performance assessment in otologic/neurotologic procedures. Extracted elements included general study characteristics (publication year, study objective, validity type, surgical procedure, and setting) and assessment approach characteristics (method of analysis, metrics assessed, source of metric data, degree of automation, and use of artificial intelligence [AI]).

RESULTS

A total of 1,141 studies were identified from the literature search. After deduplication, title/abstract screening, and full-text review, 21 studies met the inclusion criteria. All but one of the included studies focused on mastoidectomy. Most studies assessed performance exclusively in VR-simulated mastoidectomy (n = 12) as opposed to cadaveric, 3D-printed, or live dissections. The majority of studies concentrated on establishing internal validity of their assessment methods (n = 13). Performance metrics were primarily obtained through motion analysis and final product analysis. Only a minority of studies used AI, which typically involved machine learning regression or classification to predict skill levels based on automatically extracted metrics.

CONCLUSION

This scoping review explores the developing landscape of automated technical skill and performance assessment in otology and neurotology. Though progress has been made in automating assessment in the field, most investigations are narrowly focused on performance in VR-simulated mastoidectomy and lack external validity evidence. AI and computer vision (CV), which have advanced automated assessment in other surgical fields, have been underutilized in assessing performance in otology and neurotology. Future work must explore the development and validation of automated assessment approaches across a wider range of otologic and neurotologic procedures. Incorporation of novel AI/CV techniques may facilitate real-time integration of automated assessment in a broader range of simulated procedures and live surgical settings.

Virtual temporal bone simulators and their use in surgical training: a narrative review

OBJECTIVE

Temporal bone dissection is a difficult skill to acquire, and the challenge has recently been further compounded by a reduction in conventional surgical training opportunities during the coronavirus disease 2019 pandemic. Consequently, there has been renewed interest in ear simulation as an adjunct to surgical training for trainees. We review the state-of-the-art virtual temporal bone simulators for surgical training.

MATERIALS AND METHODS

A narrative review of the current literature was performed following a Medline search using a pre-determined search strategy.

RESULTS AND ANALYSIS

Sixty-one studies were included. There are five validated temporal bone simulators: Voxel-Man, CardinalSim, Ohio State University Simulator, Melbourne University's Virtual Reality Surgical Simulation and Visible Ear Simulator. The merits of each have been reviewed, alongside their role in surgical training.

CONCLUSION

Temporal bone simulators have been demonstrated to be useful adjuncts to conventional surgical training methods and are likely to play an increasing role in the future.

The parietal notch (Brammer's pointer): Accuracy of a surface landmark for temporal bone surgery

Hypothesis

The parietal notch is a reliable surface landmark of the sigmoid sinus at the sinodural angle.

Background

Currently no surface landmark approximates the anterior border of the sigmoid sinus. Additionally, the temporal line may not accurately identify the tegmen near the sinodural angle. This study examines the reliability of the parietal notch as a surface landmark of the sigmoid sinus at the sinodural angle.

Methods

Forty-seven cadaveric temporal bones were used to identify the parietal notch by two observers. The parietal notch and sinodural angle were labeled with radiopaque markers, mounted on foam, and CT imaged in the axial plane. The horizontal and vertical distances between the labeled landmarks were measured using PACS software.

Results

The parietal notch location was identified in 43/47 specimens. The notch was posterior to the sinodural angle in 90.6% and superior in 65% of the specimens. The average horizontal and vertical distance between the two landmarks was 6.1 mm (SD = 5.4) and 0.8 mm (SD = 8.7), respectively. In 60% of the specimens the parietal notch was within 6 mm of the sinodural angle in the horizontal dimension.

Conclusions

The parietal notch is identified in most temporal bones. It also approximates the anterior boarder of the sigmoid sinus and level of the tegmen due to its proximity to the sinodural angle. The parietal notch helps to define the posterosuperior margins of a mastoid dissection and may assist surgeons during mastoid surgery.

Training in temporal bone drilling

Acquiring surgical experience in the operating room is increasingly difficult. Simulation of temporal bone drilling is therefore essential, and more and more widely used. The aim of this review is to clarify the limitations of classical surgical training, and to describe the different types of simulation available for temporal bone drilling. Systematic Medline search used the terms: "temporal bone" and training and surgery; "temporal bone" and training and drilling. Seventy-one of the 467 articles identified were relevant for this review. Various temporal bone simulators have been created to get around the limitations (ethical, financial, cultural, working time) of temporal bone drilling. They can be classified as cadaver, animal, physical or virtual models. The main advantages of physical and virtual prototyping are their ease of access, the possibility of repeating gestures on a standardised model, and the absence of ethical issues. Validation is essential before these simulators can be included in the curriculum, to ensure efficacy and thus improve patient safety in the operating room.

A review of simulation applications in temporal bone surgery

Background

Temporal bone surgery is a technically challenging and high-risk procedure in an anatomically complex area. Safe temporal bone surgery emphasizes a consummate anatomic understanding and technique development that requires the guidance of an experienced otologic surgeon and years of practice. Temporal bone simulation can augment otologic surgical training and enable rehearsal of surgical procedures.

Objectives

The purpose of this article is to provide an updated review of temporal bone simulation platforms and their uses.

Data Sources

PubMed literature search. Search terms included temporal bone, temporal bone simulation, virtual reality (VR), and presurgical planning and rehearsal.

Discussion

Various simulation platforms such as cadaveric bone, three-dimensional (3D) printed models, and VR simulation have been used for temporal bone surgery training. However, each simulation method has its drawbacks. There is a need to improve upon current simulation platforms to enhance surgical training and skills assessment, as well as a need to explore other clinically significant applications of simulation, such as preoperative planning and rehearsal, in otologic surgery.

Conclusions

There is no replacement for actual surgical experience, but high-fidelity temporal bone models such as those produced with 3D printing and computer simulation have emerged as promising tools in otolaryngologic surgery. Improvements in the fidelity of both 3D printed and VR simulators as well as integration of a standardized assessment format would allow for an expansion in the use of these simulation platforms in training and assessment.

Level of Evidence

5.

State of Robotic Mastoidectomy: Literature Review

Over the past 30 years, the application of robotics in the field of neurotology has grown. Robots are able to perform increasingly complex tasks with ever improving accuracy, allowing them to be used in a broad array of applications. A mastoidectomy, in which a drill is used to remove a portion of the mastoid part of the temporal bone at the base of the skull, is one such application. To determine the current state of neurotologic robotics in the specific context of mastoidectomy, a review of the literature was carried out. This qualitative review explores what has been done in this field to date, as well as what has yet to be done. Although the research suggests that robotics can be and has been successfully used to assist with mastoidectomy, it also suggests the incompleteness of robotic development in the field. At present, only 2 robotic systems have been approved by the U.S. Food and Drug Administration for neurosurgical use and the literature lacks evidence of meaningful clinical testing of new systems to change that. The cost of robotics also remains prohibitive. However, strides have been made, with at least 1 robot for mastoidectomy having reached the point of cadaveric trials. In addition, the research suggests some of the characteristics that should be considered when designing robots for mastoidectomy, such as burr size and the type of forces that should be applied. Overall, the outlook for robots in neurotology, particularly mastoidectomy, is bright but some hurdles still remain to be overcome.