A new approach for malleus/incus fixation: no prosthesis necessary.

Abstract

To describe a novel approach to manage malleus/incus fixation. Retrospective review of 363 patients with conductive hearing loss operated on since 1996. Academic tertiary referral center. Three hundred sixty-three patients with conductive hearing loss, an intact tympanic membrane, and without history for chronic infection underwent middle ear exploration. Three hundred forty-three had otosclerosis and underwent laser stapedotomy; the remaining 20 patients had laser release of their malleus/incus fixation. Twenty patients are presented in this paper. Nineteen patients were diagnosed with malleus fixation before surgery. One patient had a total perforation and mobility of the ossicular chain was not verified preoperatively. This patient was, intraoperatively, noted to have complete ossicular fixation. Conductive hearing loss was identified using audiometry and tuning forks. Nineteen of the 20 patients had the diagnosis confirmed using micropneumotoscopy and noting immobility of the malleus. A transcanal approach was used, and the malleus/incus fixation was released using a laser. This space was expanded upon using a drill. A 1.5-2.0 mm space was created where the ossicular fixation existed, thereby reducing the likelihood of refixation. Audiometric studies before and after intervention were compared. One to seven years of follow up are provided. Preoperative air-bone gaps ranged from 18 dB to 51 dB and averaged 33 dB. Postoperative air-bone gaps ranged from 1-36 dB and averaged 13 dB. No patients have experienced refixation. There were two complications: one perforation requiring a tympanoplasty and one patient sustaining a 20 dB high-frequency sensorineural loss, most likely secondary to inadvertent drill contact to the ossicular chain. When fixation of the malleus and/or incus is found, treatment options exist. A common technique involves removal of the incus and head of the malleus and reconstruction with an incus interposition or a partial ossicular prosthesis. Another technique proposed by the senior author (M.D.S.) is maintenance of the normal anatomy and use of the potassium-titanyl-phosphate laser and drill to free the ossicles and widen the epitympanum. This series shows successful closure of the air-bone gap with this technique.