Ex Vivo Ovine Model for Surgical and Microsurgical Training on Parotidectomy and Facial Nerve Reanimation: Proposal of Structured Training Program

Abstract

Introduction Facial nerve palsy has a great physical and psychological impact on patients, so the avoidance of facial nerve damage during surgery and its reanimation are important for Otolaryngologists and head and neck surgeons. The acquisition of anatomical knowledge and surgical training regarding the parotid surgery and facial nerve is mandatory, but not easy to achieve. Surgical simulation is a reliable alternative to the on-the-job learning. In the study, we tested an ex vivo animal model to obtain the basic and advanced skills of parotid gland surgery and facial nerve reconstruction/reanimation.

Materials and Methods A prospective cohort study has been conducted on ovine head and neck specimen. A junior resident, a senior resident, and an expert surgeon were involved in a step-by-step preplanned dissection, divided in macroscopic and microscopic. Each procedure was recorded and evaluated by an expert surgeon following an adapted rating scale.

Results A statistically significant improvement in terms of execution times and quality of the work was show in most of the surgical steps and for many quality items by the junior and senior residents, while the expert surgeon, as expected, did not show any improvement.

Discussion Our ex vivo ovine model provided the trainee with close-to-real tissues in term of elastic resistance and consistency, to learn the skills requested in a head and neck surgery, on a reproducible environment. It is mandatory to have a feedback, which focuses on the quality of the work through valid and reliable assessment of technical skills. The judgment parameters should be reproducible and focused on the specific surgical procedure. Some limitations to this study are present, such as anatomical differences between ovine and human and the limited number of study participants.

Conclusion This proposal of training program on the ex vivo ovine model for the acquisition of skills needed in head and neck surgery proved to be feasible, effective, repeatable, and cheap.

Keywords

surgical training - facial nerve - animal model

• References

• 1 Myckatyn TM, Mackinnon SE. A review of facial nerve anatomy. Semin Plast Surg 2004; 18 (01) 5-12
• 2 Dirven S, Allen JE. Physical and virtual modelling of the head and neck for surgical simulation and training. Curr Opin Otolaryngol Head Neck Surg 2016; 24 (06) 463-468
• 3 Evgeniou E, Walker H, Gujral S. The role of simulation in microsurgical training. J Surg Educ 2018; 75 (01) 171-181
• 4 Anschuetz L, Bonali M, Ghirelli M. et al. An ovine model for exclusive endoscopic ear surgery. JAMA Otolaryngol Head Neck Surg 2017; 143 (03) 247-252
• 5 Ghirelli M, Mattioli F, Federici G. et al. Ex vivo porcine larynx model for microlaryngoscopy laryngeal surgery: proposal for a structured surgical training. J Voice Off J Voice Found 2020; 34 (04) 629-635
• 6 Ianacone DC, Gnadt BJ, Isaacson G. Ex vivo ovine model for head and neck surgical simulation. Am J Otolaryngol 2016; 37 (03) 272-278
• 7 Costa AL, Cucinotta F, Fazio A. et al. Anterolateral thigh flap in a chicken model: a novel perforator training model. J Reconstr Microsurg 2019; 35 (07) 485-488
• 8 Milner TD, Okhovat S, McGuigan M, Clement WA, Kunanandam T. Feasibility of ovine and porcine models for simulation training in parotid surgery and facial nerve dissection. Eur Arch Otorhinolaryngol 2020; 277 (04) 1167-1175
• 9 Niimi Y, Matsumine H, Fukuda S. et al. Surgical anatomy of ovine facial and hypoglossal nerves for facial nerve reconstruction and regeneration research: an experimental study in sheep. Microsurgery 2020; 40 (01) 51-58
• 10 Chan W-Y, Matteucci P, Southern SJ. Validation of microsurgical models in microsurgery training and competence: a review. Microsurgery 2007; 27 (05) 494-499
• 11 Kalu PU, Atkins J, Baker D, Green CJ, Butler PEM. How do we assess microsurgical skill?. Microsurgery 2005; 25 (01) 25-29
• 12 Shulzhenko NO, Zeng W, Albano NJ. et al. Multispecialty microsurgical course utilizing the blue-blood chicken thigh model significantly improves resident comfort, confidence, and attitudes in multiple domains. J Reconstr Microsurg 2020; 36 (02) 142-150
• 13 R Core Team. R: a language and environment for statistical computing. R Foundation for Statistical Computing Vienna, Austria.. 2018 . Available at: https://www.R-project.org/. Accessed November 2, 2020
• 14 Reznick RK, MacRae H. Teaching surgical skills: changes in the wind. N Engl J Med 2006; 355 (25) 2664-2669
• 15 DePasse JM, Nzeogu MI, Travers C. et al. Early subspecialization in orthopedic surgery training. Orthopedics 2019; 42 (01) e39-e43
• 16 Alaker M, Wynn GR, Arulampalam T. Virtual reality training in laparoscopic surgery: a systematic review & meta-analysis. Int J Surg 2016; 29: 85-94
• 17 Veneziano D, Cacciamani G, Shekhar Biyani C. Simulation and training in Urology - in collaboration with ESU/ESUT. Arch Esp Urol 2018; 71 (01) 55-62
• 18 Gallagher AG, Satava RM, Shorten GD. Measuring surgical skill: a rapidly evolving scientific methodology. Surg Endosc 2013; 27 (05) 1451-1455