[Surgical anatomy of the retrotympanum: on 25 temporal bones]

Based on 25 anatomical dissections of the petrosal bone, the author presents a study on the surgical anatomy of the retrotympanum and all its constituent parts. This area often considered as the blind spot of closed techniques is explored in a more exact and complete manner with the aid of a posterior tympanotomy which is not always as easy to carry out as we might be led to believe. A description of all the parts of the retrotympanum with special attention to the sinus tympani and all the facial relations make up the main part of this study, to which the different variants found during these dissections needs to be added. This will perhaps make it possible to remove all reluctance for carrying out posterior tympanotomies as completely as possible. This article is completed by photographs of these dissections with explanatory schemas.