Ovine ear model for fully endoscopic stapedectomy training

Abstract

Endoscopic surgery of the middle ear is progressively gaining the interest of otologists, as technological advances have overcome some of its main drawbacks. The long learning curve required to master this technique, urges the search for models to practice it. After the validation of sheep's ear as a proper training model for microscopic stapedectomy, our objective is to demonstrate its adequacy for practicing stapes surgery but performed through a fully endoscopic approach. Endoscopic stapedectomy was performed by two surgeons in 40 sheep ears (20 specimens each). To analyze the effects of the learning curve on surgical success, complication rates and surgical time reduction, the sample was divided in two groups: group 1 being the first ten procedures of each surgeon, and group 2 the second set of stapedectomies. The impact of the operated side and the resection of the chordal spine were also studied. No statistically significant differences were found considering the operated side. A statistically significant improvement in some of the surgical steps was demonstrated comparing both groups and also after the resection of the chordal spine. Mean surgical time declined from 38 to 31.5 min (p < 0.05). Using this model for endoscopic stapedectomy, a learning curve was objectively demonstrated, along with other subjective appreciations such as improvement in depth perception and one-hand instrument handling. We believe that sheep ear is an optimal model for endoscopic middle ear surgery, as it allows for the acquisition of the skills required to master this technique.

Investigating the learning curve in endoscopic compared to microscopic myringotomy and ventilation tube insertion

“…Alternative simulators could be considered for future research; for instance, an ovine ear model for fully endoscopic stapedectomy training has been validated. 18 Staff variation across multiple sites is likely to diminish the effect of collection biases. Participants experience an altered angle of approach and view of the middle ear depending on handedness.…”

Endoscopic vs. microscopic stapes surgery: An anatomical feasibility study

“…However, literature showed that after 10 endoscopic stapes surgeries for an ENT surgeon experienced in microscopic stapes surgery, there was no statistically significant difference in operating time compared to the microscopic stapes surgeries nor in the amount of postoperative adverse events ( 23 ). Also, based on postoperative audiometric results, the endoscopic and the microscopic approach have similar surgical success ( 7 , 9 , 12 , 23 – 26 ). Finally, the use of an endoscope holder can facilitate the two-handed technique of stapes surgery and reduce the fatigue associated with holding the endoscope for extended periods of time ( 10 ).…”

“…Moreover, a larger proportion of scutum had to be removed using the microscopic approach than the endoscopic approach. No scutum resection reduces the likelihood of, CT manipulation and postoperative dysgeusia ( 12 ). Also, less invasive surgery might lead to less scar formation and complaints during the first weeks of the postoperative course.…”

“…Therefore, we believe that the endoscopic approach in stapes surgery deserves a place in the surgical armamentarium given its additional values. Provided that the learning curve of an inexperienced ENT surgeon will be even longer, one might preserve this innovation only for the experienced surgeon ( 12 , 23 , 25 , 26 ).…”

Feasibility of ovine and synthetic temporal bone models for simulation training in endoscopic ear surgery

“…In recent years, several authors have explored the feasibility of using different animal and synthetic models as alternatives to cadaveric temporal bone for simulation training in endoscopic ear surgery. The application of the ovine model has been explored in endoscopic procedures such as stapedectomy, 7,11 cochlear implantation, 12 middle-ear implantable devices 8 and endoscopic myringoplasty. 8,13 This is predominantly a result of the remarkable anatomical similarity and tissue quality that it shares with the cadaveric temporal bone.…”