Feasibility of a synthetic temporal bone for training in mastoidectomy: face, content, and concurrent validity

To investigate the face, content, and concurrent validity of the synthetic Pettigrew temporal bone (PTB) for mastoidectomy training as compared with cadaveric temporal bone (CTB).

A prospective evaluation study.

Participants were invited to perform a step-by-step modified radical mastoidectomy using both bones and complete a 22-item, 5-point Likert scale questionnaire. The questionnaire is divided into 4 domains: face validity (FV), global content (GC), task-specific content (TSC), and curriculum recommendation (CR).

Thirty-six experts and 89 trainees completed all tasks, 63 using CTB and 62 using PTB. The PTB median FV was 4 (IQR: 4-5), GC of 4 (IQR: 4-5), TSC of 4 (IQR: 3-4), and CR of 4 (IQR: 4-5). The CTB was rated significantly higher than PTB by both groups in all domains; CTB FV: 5 (IQR: 4-5), GC: 5 (IQR: 4-5), TSC: 5 (IQR: 4-5), and CR: 5 (IQR: 5-5), p < 0.001 for each. Trainees rated PTB significantly higher than experts in all domains. There was no statistically significant difference between experts and trainees in rating the CTB in all domains. PTB gives similar haptic feedback to CTB, allows the use of suction and irrigation, has the important landmarks painted for identification, and contains articulating ossicles. The facial nerve anatomy was found to be inaccurate around the region of the second genu.

Participants found PTB to be valid for teaching some, yet not all, aspects of mastoid surgery, and experts agreed that it could improve global transferrable otologic skills. It is essential that the facial nerve anatomy is addressed before recommending this model.