**8. Learning curve aspects**

Learning curve varies upon both the complexity of otological procedure and prior experience of the otosurgeon with endoscopic sinus surgery. Furthermore, the profile of the learning curve is expressed through two factors.

The first factor is the variation of duration of the same surgery through time. According to our experience, surgical duration decreased with time in all types of endoscopic surgeries especially in ventilation tube positioning and tympanoplasty. For cholesteatoma endoscopic removal, since it was the last to introduce in our daily practice and therefore we were already acquainted with otoendoscopic surgery, duration of surgery did not undergo a tangible reduction.

The second factor is expressed by the anatomical results obtained through time. Concerning tympanoplasty, with time, we have experienced less reperforations in the reconstruction of the successive tympanic membranes. For cholesteatoma surgery, we become more confident in cholesteatoma removal from the hidden parts of the tympanic cavity, that is, sinus tympani and epitympanum. Such an experience permitted us to approach the middle ear less invasively such as creating less intracanal atticotomy or removing intact ossicles.

Concerning ossiculoplasties, stapedotomies, and cochlear implantation, it is preferable that they are advised after having obtained a certain confidence with otoendoscopic surgery.
