Simulation in laryngology training; what should we invest in? Our experience with 64 porcine larynges and a literature review

Validation of a 3D-Printed Silicone-Based Laryngeal Model for Resident Education

OBJECTIVE

We sought to validate a laryngeal simulation model and subsequently demonstrate its efficacy in improving surgical technique.

STUDY DESIGN

Pre-post interventional study.

SETTING

Otolaryngology Program at a Tertiary Care Center.

METHODS

A low-cost, high-fidelity laryngeal model was created using a 3-dimensional-printed cast and multilayered silicone to mimic vocal fold lesions. Participants (attendings and trainees) were first given a series of tasks including mucosal vocal fold lesion resection and microflap excision of a submucosal lesion. Trainees were then provided with an instructional video from a laryngologist and asked to repeat the same tasks on the model. Performance data was then assessed using validated surveys and blinded expert reviewers.

RESULTS

Eighteen participants completed the simulation. All subjects agreed that the "simulation experience was useful" and 93% agreed "the simulator helped improve my ability to do microsurgical tasks." In the postinstruction self-evaluation, trainees reported a significant decrease in mental demand (95% confidence interval [CI]: 0.37-0.91; P = .038) and significant increase in subjective performance (95% CI: 1.51-51.89; P = .016) compared to the preinstruction self-evaluation. On the postinstruction attempt, there was a significant improvement in all domains of the adapted objective structured assessment of technical skills as measured by 3 blinded, expert reviewers.

DISCUSSION

This study demonstrates the usefulness of a silicone larynx model and the value of instructional video in developing laryngeal microsurgical skills. Participants positively reviewed the laryngeal model and trainees saw both a subjective and objective improvement indicating tangible operative benefits from the use of this laryngeal simulation.

Quality of Office-based Procedure Training During Laryngology Fellowship

OBJECTIVES

The primary objective was to assess the perspectives of recent laryngology fellowship graduates on office-based procedure training, with a secondary objective to compare this with previous research on perspectives of fellowship directors.

METHODS

Recent laryngology fellowship graduates were surveyed via an online survey platform regarding post-fellowship practice and various aspects of office-based procedure training, including perceived competence, mentorship, and barriers.

RESULTS

There were 51 respondents. Seventy-six percent of respondents felt they "definitely" received adequate office procedure training. Number of procedures as primary surgeon was significantly associated with perception of adequate training (OR 1.54, 95% CI: 1.08-2.19, p = 0.018) and high post-fellowship office procedure volume (OR 1.56, 95% CI: 1.02-2.39, p = 0.040). Fellows reported a lower percentage of procedures as primary surgeons compared with program directors (46.8% vs. 61.9%, p = 0.028). Fellows and directors agreed that informal debriefs were more commonly employed than more structured training elements such as checklists and simulators. Of nine office procedures, laryngeal electromyography, KTP laser, and transnasal esophagoscopy had the greatest decreases in practice after training.

CONCLUSION

Although most recent laryngology fellowship graduates endorse adequate office-based procedure training, a range of individual experiences exists, and office procedure volume, both overall and across individual procedures, may decrease after fellowship. Fellows performing office procedures as primary surgeons may be linked to perceived quality of training and post-fellowship volume.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:1802-1806, 2024.

Development and Validation of a Laryngeal Microsurgery Simulation Training System for Otolaryngology Residents

OBJECTIVE

This study aims to create a synthetic laryngeal microsurgery simulation model and training program; to assess its face, content, and construct validity; and to review the available phonomicrosurgery simulation models in the literature.

STUDY DESIGN

Nonrandomly assigned control study.

SETTING

Simulation training course for the otolaryngology residency program at Pontificia Universidad Católica de Chile.

METHODS

Resident (postgraduate year 1 [PGY1]/PGY2) and expert groups were recruited. A laryngeal microsurgery synthetic model was developed. Nine tasks were designed and assessed through a set of programmed exercises with increasing difficulty, to fulfill 5 surgical competencies. Imperial College Surgical Assessment Device sensors applied to the participants' hands measured time and movements. The activities were video-recorded and blindly assessed by 2 laryngologists using a specific and global rating scale (SRS and GRS). A 5-point Likert survey assessing validity was completed by experts.

RESULTS

Eighteen participants were recruited (14 residents and 4 experts). Experts performed significantly better than residents in the SRS (p = .003), and GRS (p = .004). Internal consistency was demonstrated for the SRS (α = .972, p < .001). Experts had a shorter execution time (p = .007), and path length with the right hand (p = .04). The left hand did not show significant differences. The survey assessing validity resulted in a median 36 out of 40 points score for face validity; and 43 out of 45 points score, for global content validity. The literature review revealed 20 available phonomicrosurgery simulation models, only 6 with construct validity.

CONCLUSION

The face, content, and construct validity of the laryngeal microsurgery simulation training program were established. It could be replicated and incorporated into residents' curricula.

Development and validation of a 3D laryngeal model in surgical skills training

OBJECTIVE

To present and validate a new simulation model for endoscopic phonomicrosurgery training as an improved teaching method.

METHODS

A low-cost artificial model was assembled using 3D printing, silicone, and gelatin. The study was designed to test the model's ability to carry out training and teaching of endoscopic phonomicrosurgery. The synthetic model was built to simulate normal and pathological vocal folds such as polyps, intracordal cysts and keratoses, made of silicone and gelatin and embedded in a larynx framework made by 3D printing. Simulations of endoscopic surgical procedures were performed and documented through photographs and videos and the images were submitted to the evaluation of a group of 17 otorhinolaryngologists who used a Likert scale questionnaire. The responses were submitted to an agreement analysis using the sum of the scores obtained for the responses as an appropriate level of validation. Cronbach's alpha index was calculated to measure the degree of the questionnaire internal consistency.

RESULT

The evaluations indicated maximum approval for the model adequacy for use in practical classes and for the teaching of the procedures, as well as in the overall satisfaction with the model in the use of surgical training.

CONCLUSION

The present proposal for training laryngeal endoscopic surgery in a 3D synthetic model is a viable option according to the validation methodology used in the present study.

Office-Based Procedure Training in Laryngology Fellowship Programs

OBJECTIVE

To assess the current practices and challenges of training office-based procedures to laryngology fellows in the United States.

METHODS

An anonymous web-based survey study was distributed to laryngology fellowship program directors, as listed by the American Laryngological Association. The survey was a 19-item questionnaire with free-text, Likert scale, and multiple-choice answers.

RESULTS

Twenty-two of 27 program directors (81.4%) replied to the survey. Many programs (8/16) have three or more laryngologists and do more than 10 procedures each week (10/16). Sixty-nine percent (11/16) of directors had not been trained for office procedures in their fellowship. The fellows are allowed to be primary surgeon on 68.75% and 75% of vocal fold augmentation and laser procedures, respectively. The expected competencies for these procedures on graduation are average-moderate and moderate. When program directors asked about the methods used for training, a minority of them use simulators (2/16), procedural checklists (2/16), or structured debriefing (2/16). The most commonly used methods were case-based troubleshooting (13/16) and unstructured debriefing (13/16). Patients being awake and patients' expectations are seen as the most important obstacles. Most of the directors thought office-based procedure training could be improved (14/16). The most common suggestions were using step-wise checklists, simulator-labs, and formal debriefings.

CONCLUSION

This is the first study evaluating the training of office-based laryngeal procedures during laryngology fellowship. Given the increasing importance of these procedures in practice and the herein identified barriers and need for improvement, fellowships should investigate the use of systematic training tools to improve fellow competency with office-based procedures. Laryngoscope, 131:2054-2058, 2021.

Creating a Validated Simulation Training Curriculum in Otolaryngology

Purpose of Review

Simulation-based training is an integral component of surgical training. It allows practice of technical skills within a safe environment without compromising patient safety. This article seeks to review current virtual and non-virtual reality simulation models within the literature and review their validation status.

Recent Findings

Many simulation models exist within otolaryngology and are currently being used for education. New models are also continuously being developed; however, validity should be proven for the models before incorporating their use for educational purposes. Validity should be determined by experts and trainees themselves.

Summary

A validated simulation curriculum should be incorporated within the otolaryngology training programme. A curriculum based on the current training programme at our institution serves as an exemplar for local adoption.

Validation of Animal Models for Simulation Training in Pediatric Laryngotracheal Reconstruction

OBJECTIVES

To assess and compare the face (FV) and content validity (CV) of three ex vivo animal models for simulation training in pediatric laryngotracheal reconstruction (LTR).

METHODS

Feasibility of performing LTR was assessed on the head and neck of three different animals (lamb/suckling-pig/rabbit) and laryngeal dimensions and qualitative observations were recorded. A 19-item five-point Likert scale questionnaire was completed for each model to assess FV and CV. Data was prospectively collected and analyzed using descriptive and nonparametric statistics.

RESULTS

All three models were suitable for LTR simulation with laryngeal dimensions corresponding to 0-2 years (rabbit), 5-10 (pig) and >10 years (lamb model). Five trainees and five expert pediatric otolaryngologists performed LTR on each model. The overall median FV score was 5 for the lamb model (IQR 4-5), 3 for the rabbit (IQR 2-3), and 4 for the pig (IQR 4-4). The overall median CV score was 5 for the lamb (IQR 5-5), 2 for the rabbit (IQR 2-3), and 4 for the pig model (IQR 4-4). Comparison of the models demonstrated the lamb to be favored as the most realistic and practical model for simulation training in pediatric LTR, with both the lamb and the porcine model attaining validation thresholds.

CONCLUSION

Our study is the first comparative validation assessment of animal models for use in pediatric LTR simulation and it supports the use of ex vivo lamb and porcine models for use in LTR surgical skills training. The lamb model was the favored simulation model while the rabbit was considered inferior for simulation training in pediatric LTR.

LEVEL OF EVIDENCE

3b.

A systematic review of simulated laryngotracheal reconstruction animal models

OBJECTIVES

Review of the literature to identify practical, high-fidelity, commercially available animal models for simulation training and surgical skills maintenance in laryngotracheal reconstruction (LTR).

METHODS

A systematic review of PubMed and Embase databases was conducted independently by two authors, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Search terms included "laryngotracheal reconstruction," "laryngotracheoplasty," "pig and larynx," "sheep and larynx," and "rabbit and larynx." Articles were then assessed, identifying model cost and availability, model validation, feasibility as a training tool, and verisimilitude to pediatric LTR.

RESULTS

In total, 79 articles were considered suitable for inclusion in the study, incorporating both in vitro and in vivo models. Models utilized included rabbit (n = 69), pig (n = 7), sheep (n = 1), and goat (n = 2). The rabbit model was similar in size to the neonate, but differences in laryngeal anatomy and cartilage texture made graft insertion difficult. The anatomy of the pig, sheep, and goat larynges more closely resembled the pediatric patient, allowing improved grafting, but corresponded more in size to that of an older child. Commercial availability of the pig and sheep was considered greatest, and was reflected in cost. None of the animal models identified in the literature have been validated as a simulation tool.

CONCLUSIONS

The rabbit, sheep and pig models seemed to demonstrate the greatest potential for use as advanced pediatric airway surgery simulation models, with the rabbit model being most utilized in the literature. However, as yet there have been no models formally validated as a simulation training tool. Laryngoscope, 129:235-243, 2019.

Ex vivo ovine model for teaching open laryngotracheal surgery

Objective

To develop an animal model for teaching open laryngotracheal surgical procedures.

Methods

The heads and necks from 5 pre-pubescent sheep were harvested after humane anesthesia. After 2–5 days to allow for rigor mortis to resolve, a specimen was supported with sandbags on an operating table. Operative procedures including tracheotomy, medialization laryngoplasty, anterior cartilage grafting, tracheal resection with primary anastomosis, and laryngectomy with closure of the pharynx were attempted.

Results

The ovine head and neck provided an accurate model for simulation of all attempted procedures. Ovine tissue resembled that of humans in mechanical properties and handling. Postsurgical endoscopy confirmed graft alignment.

Conclusions

The sheep head and neck provides an inexpensive, realistic, and safe model for surgical training for a variety of open laryngotracheal procedures. This is particularly relevant given the recent emphasis on surgical simulation and the relative rarity of some of these procedures in residency training.

Using simulators to teach pediatric airway procedures in an international setting

INTRODUCTION

There has been a growing shift towards endoscopic management of laryngeal procedures in pediatric otolaryngology. There still appears to be a shortage of pediatric otolaryngology programs and children's hospitals worldwide where physicians can learn and practice these skills. Laryngeal simulation models have the potential to be part of the educational training of physicians who lack exposure to relatively uncommon pediatric otolaryngologic pathology.

OBJECTIVES

The objective of this study was to assess the utility of pediatric laryngeal models to teach laryngeal pathology to physicians at an international meeting.

METHODS

Pediatric laryngeal models were assessed by participants at an international pediatric otolaryngology meeting. Participants provided demographic information and previous experience with pediatric airways. Participants then performed simulated surgery on these models and evaluated them using both a previously validated Tissue Likeness Scale and a pre-simulation to post-simulation confidence scale.

RESULTS

Participants reported significant subjective improvement in confidence level after use of the simulation models (p < 0.05). Participants reported realistic representations of human anatomy and pathology. The models' tissue mechanics were adequate to practice operative technique including the ability to incise, suture, and suspend models.

CONCLUSION

The pediatric laryngeal models demonstrate high quality anatomy, which is easy manipulated with surgical instruments. These models allow both trainees and surgeons to practice time-sensitive airway surgeries in a safe and controlled environment.

Current Status of Simulation in Otolaryngology: A Systematic Review

OBJECTIVE

Otolaryngology is a highly technical and demanding specialty and the requirements for surgical trainees to acquire proficiency remains challenging. Simulation has been purported to be an effective tool in assisting with this. The aim of this systematic review is to identify the available otolaryngology simulators, their status of validation, and evaluation the level of evidence behind each training model and thereby establish a level of recommendation.

DESIGN

PubMed, ERIC, and Google Scholar databases were searched for articles that described otolaryngology simulators or training models between 1980 and April 2016. Any validation studies for simulators were also retrieved. Titles and abstracts were screened for relevance using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. Level of evidence (LoE) and Level of recommendation (LoR) was awarded to each study and model, respectively.

RESULTS

A total of 70 studies were identified describing 64 simulators. Out of these, at least 54 simulators had 1 validation study. Simulators for the ear and temporal bone surgery were the most common (n = 32), followed by laryngeal and throat (n = 20) and endoscopic sinus surgery (n = 12). Face validity was evaluated by 29 studies, 20 attempted to show construct, 20 assessed content, 20 transfer, and only 2 assessed concurrent validity. Of the validation assessments, 2 were classified as Level 1b, 10 Level 2a, and 48 Level 2b. No simulators received the highest LoR, but 8 simulators received a LoR of 2.

CONCLUSIONS

Despite the lack of evidence in outcome studies and limited number of high-validity otolaryngology simulators, the role of simulation continues to grow across surgical specialties Hence, it is imperative that the simulators are of high validity and construct for trainees to practice and rehearse surgical skills to develop confidence.

Novel Dissection Station for Endolaryngeal Microsurgery and Laser Surgery: Development and Dissection Course Experience

Objective

We aimed to develop and validate an ex vivo dissection station for endolaryngeal surgery suitable for different kinds of laryngeal specimen and any type of operating technique (CO2 laser, cold instruments by endoscopic or microscopic techniques).

Study Design

Experimental construction and validation of a highly specialized dissection station.

Setting

Laboratory and international dissection course.

Methods

We designed a lightweight dissection station made of polycarbonate resin approved for use with a CO2 laser. The cylindrical box hosts an articulated laryngeal support. The laryngoscope is positioned on an articulated arm, which is fixed on the construction’s footplate. Validation of the larynx box was performed during an international dissection course on laryngeal surgery held in January 2016.

Results

We assessed the suitability of our novel dissection station among specialized laryngologists with a mean experience of 14 years. Feedback from the participants was very positive, with a mean general impression of 9.5 (out of 10 points) and a recommendation score of 9.6 for further use. Its utility in transforming the taught surgical steps into daily practice has been highly recognized, with a score of 9.5.

Conclusion

The lightweight and transparent larynx box is suitable for any kind of laryngeal specimen, and any surgical intervention can be taught at reasonable cost. It is safe and suitable for use with CO2 lasers. Validation among experienced surgeons revealed its suitability in the teaching of endolaryngeal microsurgery and laser surgery.

Ex vivoovine model for suspension microlaryngoscopy training

Objective:

To develop an ovine model for teaching suspension laryngoscopy and phonosurgery.

Methods:

The head and neck from 10 pre-pubescent sheep were harvested following humane euthanasia at the end of anin vivoprotocol. No live animals were used in this study. The tissues were saline-perfused and refrigerated for 1–5 days. Suspension laryngoscopy was performed using adolescent Parsons and adult Kantor-Berci laryngoscopes suspended with a Benjamin-Parsons laryngoscope holder. Visualisation was achieved with 0° and 30° telescopes, and a three-chip camera and video system. Shapshay-Ossoff microlaryngeal instruments were used for endolaryngeal dissection.

Results:

Experienced laryngologists led a second year medical student through several procedures including injection laryngoplasty, hydrodissection and incision, endolaryngeal suturing, and partial cordectomy. Despite expected anatomical differences, the model proved highly realistic for suspension microlaryngoscopy.

Conclusion:

The sheep head and neck model provides an inexpensive, safe model for developing skills in suspension laryngoscopy and basic phonosurgery.

Ex vivo ovine model for head and neck surgical simulation

OBJECTIVE

To evaluate a fresh, ovine/sheep head and neck tissue model to teach otolaryngology-head and neck surgical techniques.

STUDY DESIGN

Observational animal study.

SETTING

A university animal resource facility.

METHODS

Tissue was collected from pre-pubescent sheep (n=10; mean age: 4months; mean mass: 28kg) following humane euthanasia at the end of an in vivo protocol. No live animals were used in this study. The head and neck of the sheep were disarticulated and stored at 5°C for 1-5days. The tissues were tested in a variety of simulated procedures by a medical student and four fellowship-trained otolaryngology faculty. Practicality and similarity to human surgeries were assessed.

RESULTS

While ovine head and neck structures are proportionally different, the consistencies of skin, subcutaneous tissues and bone are remarkably similar to that seen in human dissection. Particularly useful were the eyelids and orbits, facial nerve and parotid gland, mandible, anterior neck and submandibular triangle. Surgeries performed included blepharoplasty, ptosis repair, orbital floor exploration, facial nerve dissection and repair, mandibular plating, tracheotomy, laryngofissure, tracheal resection and laryngectomy. The model was also useful for flexible and microsuspension laryngoscopy.

CONCLUSION

Fresh, ovine tissue provides a readily available, anatomically compatible, affordable, model for training in otolaryngology-head and neck surgery. The use of sheep tissues carries a low risk for disease transmission and is ethically defensible. Structural variations in the sheep temporal bone, paranasal sinuses and skull base anatomy limit the usefulness of the model for surgical training in these areas.

Phonomicrosurgery simulation: A low-cost teaching model using easily accessible materials

OBJECTIVES/HYPOTHESIS

To introduce the use of a new phonomicrosurgical trainer using easily accessible materials, and to establish the effectiveness of the model.

STUDY DESIGN

The model uses a grape imbedded in gelatin, a microscope, and microlaryngeal instruments. The study was designed to test baseline differences in training levels, as well as improvement in performance after training with the simulation model.

METHODS

Thirty subjects enrolled in the Stanford University School of Medicine otolaryngology training program performed microlaryngeal surgery tasks on a grape. Tasks were designed to model both excision of a vocal fold lesion and vocal fold injection. Anonymized video recordings comparing presimulation and postsimulation training were collected and graded by an expert laryngologist. Both objective comparison of skills and subjective participant surveys were analyzed.

RESULTS

Objectively, trainees in all groups made statistically significant improvements across all tested variables, including microscope positioning, creation of a linear incision, elevation of epithelial flaps, excision of a crescent of tissue, vocal fold injection, preservation of remaining tissue, and time to complete all tasks. Subjectively, 100% of participants felt that they had increased comfort with microlaryngeal instruments and decreased intimidation of microlaryngeal surgery after completing the simulation training. This appreciation of skills was most notable and statistically significant in the intern trainees.

CONCLUSION

Microlaryngeal surgical simulation is a tool that can be used to train residents to prepare them for phonomicrosurgical procedures at all levels of training. Our low-cost model with accessible materials can be easily duplicated and used to introduce trainees to microlaryngeal surgery or improve skills of more senior trainees.

LEVEL OF EVIDENCE

NA Laryngoscope, 126:2528-2533, 2016.