This report describes a case of stapedial superstructure fixation with a mobile footplate, which is a rare occurrence among the ossicular malformations that cause conductive hearing impairment. A 44-year-old man with symptoms of left-sided hearing impairment since childhood presented to our department. The eardrum was normal, and pure tone audiometry showed conductive hearing impairment with a three-frequency (500, 1000, and 2000 Hz) mean of 53.3 dB and a normal tympanogram result. An abnormal shadow was observed on the internal side of the left stapes during the three-dimensional reconstruction of computed tomography. We suspected a stapes malformation and performed an exploratory tympanotomy with transcanal endoscopic ear surgery. We found a bony bar between the superstructure of the stapes and the promontory. The mobility of the stapes was significantly improved by removing the bony bar. Findings of postoperative audiometry were normal after surgery. The treatment of such cases of stapedial fixation is simple, and the prognosis of hearing gain after surgery is quite good. Thus, regarding the treatment of patients with conductive hearing impairment, clinicians and surgeons should be aware of the possibility of single stapedial superstructure fixation.
Keywords: TEES; endoscopic surgery; fixation; malformation; stapes; superstructure.