Atrophy of the long process of the incus of unknown origin – a rare cause of acquired conductive hearing loss. Clinical case report and a mini-review of literature

Abstract

Introduction: Among the pediatric population, the most common cause of conductive hearing loss is exudative otitis media. If fluid is not present in the tympanic cavity, an assessment of the middle ear transmission system is recommended. Aim: To present a clinical case of atrophy of the long process of the incus in a 17-year-old patient with a 10-year history of conductive hearing loss, exhibiting an air-bone gap of 30 to 50 dB in the right ear qualified for exploratory tympanotomy. Literature review of internet databases to identify similar clinical cases. Material and methods: CARE guidelines were used to standardize the description of the clinical case. Surgical treatment included an exploratory tympanotomy using an endaural approach, visualizing atrophy of the long process of the incus and the connective tissue band connecting the stapes head to the lateral wall of the tympanic cavity. The eardrum was preserved. An ossiculoplasty was performed using autogenic materials – interposition of the incus. Internet databases PubMed and Scopus were searched using the search string „Incus atrophy” OR „Incus necrosis” AND NOT „Stapedectomy”. Results: On follow-up one month after surgery a hearing improvement was observed with a reduction in air-bone gap to 10–15 dB. No complications were observed. Discussion: Atrophy of the long process of unknown origin is a very rare cause of acquired conductive hearing loss. A review of literature revealed 8 manuscripts describing similar cases, which are presented and discussed in the manuscript. Ossiculoplasty in such cases might be performed using autogenic or artificial materials as partial ossicular prostheses or bone cement. Conclusions: Careful evaluation of imaging studies and hearing tests can often identify a defect in the conductive system; exploratory tympanotomy is often required. In cases such as the one presented, interposition of the incus might be a viable option.