Preoperative prediction of the expected opening width of the posterior tympanotomy using Otoplan

Background Access to the round window membrane (RF) via posterior tympanotomy (PT) in cochlear implantation (CI) varies interindividually. Despite computed tomographic (CT) imaging, the surgical field of view through the PT is difficult to anticipate for CI. Otoplan provides an automatic trajectory for CI using CT images. In the present study, we analyzed how much the bore channel of the PT, especially the chordo-facial angle, needs to be opened up depending on the anatomical relationships of the guide structures to the automatic trajectory in Otoplan.