Arnaud DeVeze, Omar Bacha, Jean-Pierre Lavielle, Jacques Magnan

Department of Otolaryngology Head and Neck Surgery, Hôpital Nord, Marseille, France

■ OBJECTIVES: Spontaneous or postoperative blunting, lateralization of the tympanic membrane and obliteration of the external auditory canal are still challenging situations. Numerous patients still remain in medical impasse, with permanent conductive or mixed hearing loss. Middle ear implants have been recently used in mixed or conductive hearing losses situations. Their utilization in such situations could be a considerable advance in middle ear surgery. The aims of this presentation are, first to analyzed our results of rehabilitation surgery for tympanic membrane lateralization and acquired obliteration of the ear canal, second to propose a prognostic classification centered on therapeutic proposal, and third, to present our experience of middle ear implantation for mixed hearing losses.

■ METHODS: We have retrospectively analyzed 65 patients who have been operated on for such disorders. Among them, eight patients (nine ears), have underwent a middle ear implantation. The medical history, clinical and imaging findings, auditory impairment have been employed for patients’ selection. Surgical anatomical and functional results (5 frequencies pure tones average thresholds (0.25, 0.5, 1, 2 and 4 Khz), air-bone gap, pure tone average gain) have been considered to classify patients. For the implanted patients, the auditory testing have been done through loudspeakers and in free-field condition, with and without activation of the implant, and included determination of the speech intelligibility.

■ RESULTS: Among all the patients operated on for lateralization, the best results were achieved for patients with anterior blunting and lateralization of a thin tympanic membrane. The technique of ossiculoplasty strictly done through a posterior tympanotomy without elevation of the ear canal skin and the drum gave the best auditory performance. The patients with proximal lateralization, annular blunting or ear canal obliteration had poor surgical functional results. Conversely, the patients who have been implanted benefited for a mean postoperative gain of 40.5 dB (range 28 - 57 dB).