Congenital Familial Fixation of the Malleus

Abstract

We present a familial association of radiographically and surgically demonstrated mallear fixation with concurrent stapedial abnormality and dehiscence of the facial nerve in a father and son, including history, physical findings, surgical findings, radiologic analyses, and a literature review. A 12-year-old boy presented with long-term left-sided conductive hearing loss, and was found to have mallear fixation and a dehiscent facial nerve on a computed tomographic (CT) scan of the temporal bone. Release of the malleus was performed at surgery, revealing hypermobility of the remaining ossicular chain. A repeat CT scan of the temporal bone showed successful release of the mallear head. The patient's father later presented with bilateral hearing loss, and a CT scan of the temporal bones showed bilateral osseous fixation of the mallear head to the tegmen and bilateral facial nerve dehiscences. He underwent right middle ear exploration, but release of the malleus was not performed because of the risk to the dehiscent facial nerve. The stapes crurae were found to be filiform at surgery. This is the first reported familial association of mallear fixation. Mallear fixation with facial nerve dehiscence and an abnormal stapes occurring in a parent and his child is interesting embryologically, and suggests that these anomalies may be genetically linked.