Tympanosclerosis may involve the tympanic membrane, the ossicles, as well as the oval and round window niche, respectively. The surgical treatment of the obliterated oval window niche is most challenging. Beside stapesplasty, vibroplasty with coupling the floating mass transducer (FMT) onto the round window niche and into a new, so-called third window is indicated. In the latter situation, dril...